Commit 3c0c5ed4 authored by Tim Hockin's avatar Tim Hockin

Move deps from _workspace/ to vendor/

godep restore pushd $GOPATH/src/github.com/appc/spec git co master popd go get go4.org/errorutil rm -rf Godeps godep save ./... git add vendor git add -f $(git ls-files --other vendor/) git co -- Godeps/LICENSES Godeps/.license_file_state Godeps/OWNERS
parent 899f9b4e

Too many changes to show.

To preserve performance only 1000 of 1000+ files are displayed.

...@@ -49,8 +49,8 @@ ...@@ -49,8 +49,8 @@
}, },
{ {
"ImportPath": "github.com/appc/spec/schema", "ImportPath": "github.com/appc/spec/schema",
"Comment": "v0.7.4-6-g5d54e27", "Comment": "v0.7.4-43-gd22f52b",
"Rev": "5d54e27f1764a0309eafe12c9df7bac03f241646" "Rev": "d22f52bfeba06614d37c7aa1ad6fd76d8fdb2ba8"
}, },
{ {
"ImportPath": "github.com/armon/go-metrics", "ImportPath": "github.com/armon/go-metrics",
...@@ -141,10 +141,6 @@ ...@@ -141,10 +141,6 @@
"Rev": "ee4a0888a9abe7eefe5a0992ca4cb06864839873" "Rev": "ee4a0888a9abe7eefe5a0992ca4cb06864839873"
}, },
{ {
"ImportPath": "github.com/camlistore/go4/errorutil",
"Rev": "3b6feb5cf32f573fb124905de36a54c24ee14ac1"
},
{
"ImportPath": "github.com/codegangsta/negroni", "ImportPath": "github.com/codegangsta/negroni",
"Comment": "v0.1-62-g8d75e11", "Comment": "v0.1-62-g8d75e11",
"Rev": "8d75e11374a1928608c906fe745b538483e7aeb2" "Rev": "8d75e11374a1928608c906fe745b538483e7aeb2"
...@@ -1041,6 +1037,10 @@ ...@@ -1041,6 +1037,10 @@
"Rev": "5292687f5379e01054407da44d7c4590a61fd3de" "Rev": "5292687f5379e01054407da44d7c4590a61fd3de"
}, },
{ {
"ImportPath": "go4.org/errorutil",
"Rev": "03efcb870d84809319ea509714dd6d19a1498483"
},
{
"ImportPath": "golang.org/x/crypto/bcrypt", "ImportPath": "golang.org/x/crypto/bcrypt",
"Rev": "c84e1f8e3a7e322d497cd16c0e8a13c7e127baf3" "Rev": "c84e1f8e3a7e322d497cd16c0e8a13c7e127baf3"
}, },
...@@ -1139,7 +1139,7 @@ ...@@ -1139,7 +1139,7 @@
}, },
{ {
"ImportPath": "k8s.io/heapster/metrics/api/v1/types", "ImportPath": "k8s.io/heapster/metrics/api/v1/types",
"Comment": "v1.1.0-beta1", "Comment": "v1.1.0-beta1-15-gde510e4",
"Rev": "de510e4bdcdea96722b5bde19ff0b7a142939485" "Rev": "de510e4bdcdea96722b5bde19ff0b7a142939485"
}, },
{ {
......
// +build !windows,!plan9,!solaris
package bolt
import (
"fmt"
"os"
"syscall"
"time"
"unsafe"
)
// flock acquires an advisory lock on a file descriptor.
func flock(f *os.File, exclusive bool, timeout time.Duration) error {
var t time.Time
for {
// If we're beyond our timeout then return an error.
// This can only occur after we've attempted a flock once.
if t.IsZero() {
t = time.Now()
} else if timeout > 0 && time.Since(t) > timeout {
return ErrTimeout
}
flag := syscall.LOCK_SH
if exclusive {
flag = syscall.LOCK_EX
}
// Otherwise attempt to obtain an exclusive lock.
err := syscall.Flock(int(f.Fd()), flag|syscall.LOCK_NB)
if err == nil {
return nil
} else if err != syscall.EWOULDBLOCK {
return err
}
// Wait for a bit and try again.
time.Sleep(50 * time.Millisecond)
}
}
// funlock releases an advisory lock on a file descriptor.
func funlock(f *os.File) error {
return syscall.Flock(int(f.Fd()), syscall.LOCK_UN)
}
// mmap memory maps a DB's data file.
func mmap(db *DB, sz int) error {
// Map the data file to memory.
b, err := syscall.Mmap(int(db.file.Fd()), 0, sz, syscall.PROT_READ, syscall.MAP_SHARED|db.MmapFlags)
if err != nil {
return err
}
// Advise the kernel that the mmap is accessed randomly.
if err := madvise(b, syscall.MADV_RANDOM); err != nil {
return fmt.Errorf("madvise: %s", err)
}
// Save the original byte slice and convert to a byte array pointer.
db.dataref = b
db.data = (*[maxMapSize]byte)(unsafe.Pointer(&b[0]))
db.datasz = sz
return nil
}
// munmap unmaps a DB's data file from memory.
func munmap(db *DB) error {
// Ignore the unmap if we have no mapped data.
if db.dataref == nil {
return nil
}
// Unmap using the original byte slice.
err := syscall.Munmap(db.dataref)
db.dataref = nil
db.data = nil
db.datasz = 0
return err
}
// NOTE: This function is copied from stdlib because it is not available on darwin.
func madvise(b []byte, advice int) (err error) {
_, _, e1 := syscall.Syscall(syscall.SYS_MADVISE, uintptr(unsafe.Pointer(&b[0])), uintptr(len(b)), uintptr(advice))
if e1 != 0 {
err = e1
}
return
}
package bolt
import (
"fmt"
"os"
"syscall"
"time"
"unsafe"
"golang.org/x/sys/unix"
)
// flock acquires an advisory lock on a file descriptor.
func flock(f *os.File, exclusive bool, timeout time.Duration) error {
var t time.Time
for {
// If we're beyond our timeout then return an error.
// This can only occur after we've attempted a flock once.
if t.IsZero() {
t = time.Now()
} else if timeout > 0 && time.Since(t) > timeout {
return ErrTimeout
}
var lock syscall.Flock_t
lock.Start = 0
lock.Len = 0
lock.Pid = 0
lock.Whence = 0
lock.Pid = 0
if exclusive {
lock.Type = syscall.F_WRLCK
} else {
lock.Type = syscall.F_RDLCK
}
err := syscall.FcntlFlock(f.Fd(), syscall.F_SETLK, &lock)
if err == nil {
return nil
} else if err != syscall.EAGAIN {
return err
}
// Wait for a bit and try again.
time.Sleep(50 * time.Millisecond)
}
}
// funlock releases an advisory lock on a file descriptor.
func funlock(f *os.File) error {
var lock syscall.Flock_t
lock.Start = 0
lock.Len = 0
lock.Type = syscall.F_UNLCK
lock.Whence = 0
return syscall.FcntlFlock(uintptr(f.Fd()), syscall.F_SETLK, &lock)
}
// mmap memory maps a DB's data file.
func mmap(db *DB, sz int) error {
// Map the data file to memory.
b, err := unix.Mmap(int(db.file.Fd()), 0, sz, syscall.PROT_READ, syscall.MAP_SHARED|db.MmapFlags)
if err != nil {
return err
}
// Advise the kernel that the mmap is accessed randomly.
if err := unix.Madvise(b, syscall.MADV_RANDOM); err != nil {
return fmt.Errorf("madvise: %s", err)
}
// Save the original byte slice and convert to a byte array pointer.
db.dataref = b
db.data = (*[maxMapSize]byte)(unsafe.Pointer(&b[0]))
db.datasz = sz
return nil
}
// munmap unmaps a DB's data file from memory.
func munmap(db *DB) error {
// Ignore the unmap if we have no mapped data.
if db.dataref == nil {
return nil
}
// Unmap using the original byte slice.
err := unix.Munmap(db.dataref)
db.dataref = nil
db.data = nil
db.datasz = 0
return err
}
/*
Package bolt implements a low-level key/value store in pure Go. It supports
fully serializable transactions, ACID semantics, and lock-free MVCC with
multiple readers and a single writer. Bolt can be used for projects that
want a simple data store without the need to add large dependencies such as
Postgres or MySQL.
Bolt is a single-level, zero-copy, B+tree data store. This means that Bolt is
optimized for fast read access and does not require recovery in the event of a
system crash. Transactions which have not finished committing will simply be
rolled back in the event of a crash.
The design of Bolt is based on Howard Chu's LMDB database project.
Bolt currently works on Windows, Mac OS X, and Linux.
Basics
There are only a few types in Bolt: DB, Bucket, Tx, and Cursor. The DB is
a collection of buckets and is represented by a single file on disk. A bucket is
a collection of unique keys that are associated with values.
Transactions provide either read-only or read-write access to the database.
Read-only transactions can retrieve key/value pairs and can use Cursors to
iterate over the dataset sequentially. Read-write transactions can create and
delete buckets and can insert and remove keys. Only one read-write transaction
is allowed at a time.
Caveats
The database uses a read-only, memory-mapped data file to ensure that
applications cannot corrupt the database, however, this means that keys and
values returned from Bolt cannot be changed. Writing to a read-only byte slice
will cause Go to panic.
Keys and values retrieved from the database are only valid for the life of
the transaction. When used outside the transaction, these byte slices can
point to different data or can point to invalid memory which will cause a panic.
*/
package bolt
package bolt
import "errors"
// These errors can be returned when opening or calling methods on a DB.
var (
// ErrDatabaseNotOpen is returned when a DB instance is accessed before it
// is opened or after it is closed.
ErrDatabaseNotOpen = errors.New("database not open")
// ErrDatabaseOpen is returned when opening a database that is
// already open.
ErrDatabaseOpen = errors.New("database already open")
// ErrInvalid is returned when a data file is not a Bolt-formatted database.
ErrInvalid = errors.New("invalid database")
// ErrVersionMismatch is returned when the data file was created with a
// different version of Bolt.
ErrVersionMismatch = errors.New("version mismatch")
// ErrChecksum is returned when either meta page checksum does not match.
ErrChecksum = errors.New("checksum error")
// ErrTimeout is returned when a database cannot obtain an exclusive lock
// on the data file after the timeout passed to Open().
ErrTimeout = errors.New("timeout")
)
// These errors can occur when beginning or committing a Tx.
var (
// ErrTxNotWritable is returned when performing a write operation on a
// read-only transaction.
ErrTxNotWritable = errors.New("tx not writable")
// ErrTxClosed is returned when committing or rolling back a transaction
// that has already been committed or rolled back.
ErrTxClosed = errors.New("tx closed")
// ErrDatabaseReadOnly is returned when a mutating transaction is started on a
// read-only database.
ErrDatabaseReadOnly = errors.New("database is in read-only mode")
)
// These errors can occur when putting or deleting a value or a bucket.
var (
// ErrBucketNotFound is returned when trying to access a bucket that has
// not been created yet.
ErrBucketNotFound = errors.New("bucket not found")
// ErrBucketExists is returned when creating a bucket that already exists.
ErrBucketExists = errors.New("bucket already exists")
// ErrBucketNameRequired is returned when creating a bucket with a blank name.
ErrBucketNameRequired = errors.New("bucket name required")
// ErrKeyRequired is returned when inserting a zero-length key.
ErrKeyRequired = errors.New("key required")
// ErrKeyTooLarge is returned when inserting a key that is larger than MaxKeySize.
ErrKeyTooLarge = errors.New("key too large")
// ErrValueTooLarge is returned when inserting a value that is larger than MaxValueSize.
ErrValueTooLarge = errors.New("value too large")
// ErrIncompatibleValue is returned when trying create or delete a bucket
// on an existing non-bucket key or when trying to create or delete a
// non-bucket key on an existing bucket key.
ErrIncompatibleValue = errors.New("incompatible value")
)
package bolt
import (
"fmt"
"os"
"sort"
"unsafe"
)
const pageHeaderSize = int(unsafe.Offsetof(((*page)(nil)).ptr))
const minKeysPerPage = 2
const branchPageElementSize = int(unsafe.Sizeof(branchPageElement{}))
const leafPageElementSize = int(unsafe.Sizeof(leafPageElement{}))
const (
branchPageFlag = 0x01
leafPageFlag = 0x02
metaPageFlag = 0x04
freelistPageFlag = 0x10
)
const (
bucketLeafFlag = 0x01
)
type pgid uint64
type page struct {
id pgid
flags uint16
count uint16
overflow uint32
ptr uintptr
}
// typ returns a human readable page type string used for debugging.
func (p *page) typ() string {
if (p.flags & branchPageFlag) != 0 {
return "branch"
} else if (p.flags & leafPageFlag) != 0 {
return "leaf"
} else if (p.flags & metaPageFlag) != 0 {
return "meta"
} else if (p.flags & freelistPageFlag) != 0 {
return "freelist"
}
return fmt.Sprintf("unknown<%02x>", p.flags)
}
// meta returns a pointer to the metadata section of the page.
func (p *page) meta() *meta {
return (*meta)(unsafe.Pointer(&p.ptr))
}
// leafPageElement retrieves the leaf node by index
func (p *page) leafPageElement(index uint16) *leafPageElement {
n := &((*[0x7FFFFFF]leafPageElement)(unsafe.Pointer(&p.ptr)))[index]
return n
}
// leafPageElements retrieves a list of leaf nodes.
func (p *page) leafPageElements() []leafPageElement {
return ((*[0x7FFFFFF]leafPageElement)(unsafe.Pointer(&p.ptr)))[:]
}
// branchPageElement retrieves the branch node by index
func (p *page) branchPageElement(index uint16) *branchPageElement {
return &((*[0x7FFFFFF]branchPageElement)(unsafe.Pointer(&p.ptr)))[index]
}
// branchPageElements retrieves a list of branch nodes.
func (p *page) branchPageElements() []branchPageElement {
return ((*[0x7FFFFFF]branchPageElement)(unsafe.Pointer(&p.ptr)))[:]
}
// dump writes n bytes of the page to STDERR as hex output.
func (p *page) hexdump(n int) {
buf := (*[maxAllocSize]byte)(unsafe.Pointer(p))[:n]
fmt.Fprintf(os.Stderr, "%x\n", buf)
}
type pages []*page
func (s pages) Len() int { return len(s) }
func (s pages) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s pages) Less(i, j int) bool { return s[i].id < s[j].id }
// branchPageElement represents a node on a branch page.
type branchPageElement struct {
pos uint32
ksize uint32
pgid pgid
}
// key returns a byte slice of the node key.
func (n *branchPageElement) key() []byte {
buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos]))[:n.ksize]
}
// leafPageElement represents a node on a leaf page.
type leafPageElement struct {
flags uint32
pos uint32
ksize uint32
vsize uint32
}
// key returns a byte slice of the node key.
func (n *leafPageElement) key() []byte {
buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos]))[:n.ksize]
}
// value returns a byte slice of the node value.
func (n *leafPageElement) value() []byte {
buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos+n.ksize]))[:n.vsize]
}
// PageInfo represents human readable information about a page.
type PageInfo struct {
ID int
Type string
Count int
OverflowCount int
}
type pgids []pgid
func (s pgids) Len() int { return len(s) }
func (s pgids) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s pgids) Less(i, j int) bool { return s[i] < s[j] }
// merge returns the sorted union of a and b.
func (a pgids) merge(b pgids) pgids {
// Return the opposite slice if one is nil.
if len(a) == 0 {
return b
} else if len(b) == 0 {
return a
}
// Create a list to hold all elements from both lists.
merged := make(pgids, 0, len(a)+len(b))
// Assign lead to the slice with a lower starting value, follow to the higher value.
lead, follow := a, b
if b[0] < a[0] {
lead, follow = b, a
}
// Continue while there are elements in the lead.
for len(lead) > 0 {
// Merge largest prefix of lead that is ahead of follow[0].
n := sort.Search(len(lead), func(i int) bool { return lead[i] > follow[0] })
merged = append(merged, lead[:n]...)
if n >= len(lead) {
break
}
// Swap lead and follow.
lead, follow = follow, lead[n:]
}
// Append what's left in follow.
merged = append(merged, follow...)
return merged
}
/*
Copyright 2011 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Package errorutil helps make better error messages.
package errorutil
import (
"bufio"
"bytes"
"fmt"
"io"
"strings"
)
// HighlightBytePosition takes a reader and the location in bytes of a parse
// error (for instance, from json.SyntaxError.Offset) and returns the line, column,
// and pretty-printed context around the error with an arrow indicating the exact
// position of the syntax error.
func HighlightBytePosition(f io.Reader, pos int64) (line, col int, highlight string) {
line = 1
br := bufio.NewReader(f)
lastLine := ""
thisLine := new(bytes.Buffer)
for n := int64(0); n < pos; n++ {
b, err := br.ReadByte()
if err != nil {
break
}
if b == '\n' {
lastLine = thisLine.String()
thisLine.Reset()
line++
col = 1
} else {
col++
thisLine.WriteByte(b)
}
}
if line > 1 {
highlight += fmt.Sprintf("%5d: %s\n", line-1, lastLine)
}
highlight += fmt.Sprintf("%5d: %s\n", line, thisLine.String())
highlight += fmt.Sprintf("%s^\n", strings.Repeat(" ", col+5))
return
}
The MIT License (MIT)
Copyright (c) 2014 Jeremy Saenz
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
package negroni
import (
"log"
"net/http"
"os"
)
// Handler handler is an interface that objects can implement to be registered to serve as middleware
// in the Negroni middleware stack.
// ServeHTTP should yield to the next middleware in the chain by invoking the next http.HandlerFunc
// passed in.
//
// If the Handler writes to the ResponseWriter, the next http.HandlerFunc should not be invoked.
type Handler interface {
ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc)
}
// HandlerFunc is an adapter to allow the use of ordinary functions as Negroni handlers.
// If f is a function with the appropriate signature, HandlerFunc(f) is a Handler object that calls f.
type HandlerFunc func(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc)
func (h HandlerFunc) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
h(rw, r, next)
}
type middleware struct {
handler Handler
next *middleware
}
func (m middleware) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
m.handler.ServeHTTP(rw, r, m.next.ServeHTTP)
}
// Wrap converts a http.Handler into a negroni.Handler so it can be used as a Negroni
// middleware. The next http.HandlerFunc is automatically called after the Handler
// is executed.
func Wrap(handler http.Handler) Handler {
return HandlerFunc(func(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
handler.ServeHTTP(rw, r)
next(rw, r)
})
}
// Negroni is a stack of Middleware Handlers that can be invoked as an http.Handler.
// Negroni middleware is evaluated in the order that they are added to the stack using
// the Use and UseHandler methods.
type Negroni struct {
middleware middleware
handlers []Handler
}
// New returns a new Negroni instance with no middleware preconfigured.
func New(handlers ...Handler) *Negroni {
return &Negroni{
handlers: handlers,
middleware: build(handlers),
}
}
// Classic returns a new Negroni instance with the default middleware already
// in the stack.
//
// Recovery - Panic Recovery Middleware
// Logger - Request/Response Logging
// Static - Static File Serving
func Classic() *Negroni {
return New(NewRecovery(), NewLogger(), NewStatic(http.Dir("public")))
}
func (n *Negroni) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
n.middleware.ServeHTTP(NewResponseWriter(rw), r)
}
// Use adds a Handler onto the middleware stack. Handlers are invoked in the order they are added to a Negroni.
func (n *Negroni) Use(handler Handler) {
n.handlers = append(n.handlers, handler)
n.middleware = build(n.handlers)
}
// UseHandler adds a http.Handler onto the middleware stack. Handlers are invoked in the order they are added to a Negroni.
func (n *Negroni) UseHandler(handler http.Handler) {
n.Use(Wrap(handler))
}
// Run is a convenience function that runs the negroni stack as an HTTP
// server. The addr string takes the same format as http.ListenAndServe.
func (n *Negroni) Run(addr string) {
l := log.New(os.Stdout, "[negroni] ", 0)
l.Printf("listening on %s", addr)
l.Fatal(http.ListenAndServe(addr, n))
}
// Returns a list of all the handlers in the current Negroni middleware chain.
func (n *Negroni) Handlers() ([]Handler) {
return n.handlers
}
func build(handlers []Handler) middleware {
var next middleware
if len(handlers) == 0 {
return voidMiddleware()
} else if len(handlers) > 1 {
next = build(handlers[1:])
} else {
next = voidMiddleware()
}
return middleware{handlers[0], &next}
}
func voidMiddleware() middleware {
return middleware{
HandlerFunc(func(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {}),
&middleware{},
}
}
package negroni
import (
"fmt"
"log"
"net/http"
"os"
"runtime"
)
// Recovery is a Negroni middleware that recovers from any panics and writes a 500 if there was one.
type Recovery struct {
Logger *log.Logger
PrintStack bool
StackAll bool
StackSize int
}
// NewRecovery returns a new instance of Recovery
func NewRecovery() *Recovery {
return &Recovery{
Logger: log.New(os.Stdout, "[negroni] ", 0),
PrintStack: true,
StackAll: false,
StackSize: 1024 * 8,
}
}
func (rec *Recovery) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
defer func() {
if err := recover(); err != nil {
rw.WriteHeader(http.StatusInternalServerError)
stack := make([]byte, rec.StackSize)
stack = stack[:runtime.Stack(stack, rec.StackAll)]
f := "PANIC: %s\n%s"
rec.Logger.Printf(f, err, stack)
if rec.PrintStack {
fmt.Fprintf(rw, f, err, stack)
}
}
}()
next(rw, r)
}
package negroni
import (
"bufio"
"fmt"
"net"
"net/http"
)
// ResponseWriter is a wrapper around http.ResponseWriter that provides extra information about
// the response. It is recommended that middleware handlers use this construct to wrap a responsewriter
// if the functionality calls for it.
type ResponseWriter interface {
http.ResponseWriter
http.Flusher
// Status returns the status code of the response or 0 if the response has not been written.
Status() int
// Written returns whether or not the ResponseWriter has been written.
Written() bool
// Size returns the size of the response body.
Size() int
// Before allows for a function to be called before the ResponseWriter has been written to. This is
// useful for setting headers or any other operations that must happen before a response has been written.
Before(func(ResponseWriter))
}
type beforeFunc func(ResponseWriter)
// NewResponseWriter creates a ResponseWriter that wraps an http.ResponseWriter
func NewResponseWriter(rw http.ResponseWriter) ResponseWriter {
return &responseWriter{rw, 0, 0, nil}
}
type responseWriter struct {
http.ResponseWriter
status int
size int
beforeFuncs []beforeFunc
}
func (rw *responseWriter) WriteHeader(s int) {
rw.status = s
rw.callBefore()
rw.ResponseWriter.WriteHeader(s)
}
func (rw *responseWriter) Write(b []byte) (int, error) {
if !rw.Written() {
// The status will be StatusOK if WriteHeader has not been called yet
rw.WriteHeader(http.StatusOK)
}
size, err := rw.ResponseWriter.Write(b)
rw.size += size
return size, err
}
func (rw *responseWriter) Status() int {
return rw.status
}
func (rw *responseWriter) Size() int {
return rw.size
}
func (rw *responseWriter) Written() bool {
return rw.status != 0
}
func (rw *responseWriter) Before(before func(ResponseWriter)) {
rw.beforeFuncs = append(rw.beforeFuncs, before)
}
func (rw *responseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
hijacker, ok := rw.ResponseWriter.(http.Hijacker)
if !ok {
return nil, nil, fmt.Errorf("the ResponseWriter doesn't support the Hijacker interface")
}
return hijacker.Hijack()
}
func (rw *responseWriter) CloseNotify() <-chan bool {
return rw.ResponseWriter.(http.CloseNotifier).CloseNotify()
}
func (rw *responseWriter) callBefore() {
for i := len(rw.beforeFuncs) - 1; i >= 0; i-- {
rw.beforeFuncs[i](rw)
}
}
func (rw *responseWriter) Flush() {
flusher, ok := rw.ResponseWriter.(http.Flusher)
if ok {
flusher.Flush()
}
}
package negroni
import (
"net/http"
"path"
"strings"
)
// Static is a middleware handler that serves static files in the given directory/filesystem.
type Static struct {
// Dir is the directory to serve static files from
Dir http.FileSystem
// Prefix is the optional prefix used to serve the static directory content
Prefix string
// IndexFile defines which file to serve as index if it exists.
IndexFile string
}
// NewStatic returns a new instance of Static
func NewStatic(directory http.FileSystem) *Static {
return &Static{
Dir: directory,
Prefix: "",
IndexFile: "index.html",
}
}
func (s *Static) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
if r.Method != "GET" && r.Method != "HEAD" {
next(rw, r)
return
}
file := r.URL.Path
// if we have a prefix, filter requests by stripping the prefix
if s.Prefix != "" {
if !strings.HasPrefix(file, s.Prefix) {
next(rw, r)
return
}
file = file[len(s.Prefix):]
if file != "" && file[0] != '/' {
next(rw, r)
return
}
}
f, err := s.Dir.Open(file)
if err != nil {
// discard the error?
next(rw, r)
return
}
defer f.Close()
fi, err := f.Stat()
if err != nil {
next(rw, r)
return
}
// try to serve index file
if fi.IsDir() {
// redirect if missing trailing slash
if !strings.HasSuffix(r.URL.Path, "/") {
http.Redirect(rw, r, r.URL.Path+"/", http.StatusFound)
return
}
file = path.Join(file, s.IndexFile)
f, err = s.Dir.Open(file)
if err != nil {
next(rw, r)
return
}
defer f.Close()
fi, err = f.Stat()
if err != nil || fi.IsDir() {
next(rw, r)
return
}
}
http.ServeContent(rw, r, file, fi.ModTime(), f)
}
# Negroni [![GoDoc](https://godoc.org/github.com/codegangsta/negroni?status.svg)](http://godoc.org/github.com/codegangsta/negroni) [![wercker status](https://app.wercker.com/status/13688a4a94b82d84a0b8d038c4965b61/s "wercker status")](https://app.wercker.com/project/bykey/13688a4a94b82d84a0b8d038c4965b61)
Negroni é uma abordagem idiomática para middleware web em Go. É pequeno, não intrusivo, e incentiva uso da biblioteca `net/http`.
Se gosta da idéia do [Martini](http://github.com/go-martini/martini), mas acha que contém muita mágica, então Negroni é ideal.
## Começando
Depois de instalar Go e definir seu [GOPATH](http://golang.org/doc/code.html#GOPATH), criar seu primeirto arquivo `.go`. Iremos chamá-lo `server.go`.
~~~ go
package main
import (
"github.com/codegangsta/negroni"
"net/http"
"fmt"
)
func main() {
mux := http.NewServeMux()
mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
fmt.Fprintf(w, "Welcome to the home page!")
})
n := negroni.Classic()
n.UseHandler(mux)
n.Run(":3000")
}
~~~
Depois instale o pacote Negroni (**go 1.1** ou superior)
~~~
go get github.com/codegangsta/negroni
~~~
Depois execute seu servidor:
~~~
go run server.go
~~~
Agora terá um servidor web Go net/http rodando em `localhost:3000`.
## Precisa de Ajuda?
Se você tem uma pergunta ou pedido de recurso,[go ask the mailing list](https://groups.google.com/forum/#!forum/negroni-users). O Github issuses para o Negroni será usado exclusivamente para Reportar bugs e pull requests.
## Negroni é um Framework?
Negroni **não** é a framework. É uma biblioteca que é desenhada para trabalhar diretamente com net/http.
## Roteamento?
Negroni é TSPR(Traga seu próprio Roteamento). A comunidade Go já tem um grande número de roteadores http disponíveis, Negroni tenta rodar bem com todos eles pelo suporte total `net/http`/ Por exemplo, a integração com [Gorilla Mux](http://github.com/gorilla/mux) se parece com isso:
~~~ go
router := mux.NewRouter()
router.HandleFunc("/", HomeHandler)
n := negroni.New(Middleware1, Middleware2)
// Or use a middleware with the Use() function
n.Use(Middleware3)
// router goes last
n.UseHandler(router)
n.Run(":3000")
~~~
## `negroni.Classic()`
`negroni.Classic()` fornece alguns middlewares padrão que são útil para maioria das aplicações:
* `negroni.Recovery` - Panic Recovery Middleware.
* `negroni.Logging` - Request/Response Logging Middleware.
* `negroni.Static` - Static File serving under the "public" directory.
Isso torna muito fácil começar com alguns recursos úteis do Negroni.
## Handlers
Negroni fornece um middleware de fluxo bidirecional. Isso é feito através da interface `negroni.Handler`:
~~~ go
type Handler interface {
ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc)
}
~~~
Se um middleware não tenha escrito o ResponseWriter, ele deve chamar a próxima `http.HandlerFunc` na cadeia para produzir o próximo handler middleware. Isso pode ser usado muito bem:
~~~ go
func MyMiddleware(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
// do some stuff before
next(rw, r)
// do some stuff after
}
~~~
E pode mapear isso para a cadeia de handler com a função `Use`:
~~~ go
n := negroni.New()
n.Use(negroni.HandlerFunc(MyMiddleware))
~~~
Você também pode mapear `http.Handler` antigos:
~~~ go
n := negroni.New()
mux := http.NewServeMux()
// map your routes
n.UseHandler(mux)
n.Run(":3000")
~~~
## `Run()`
Negroni tem uma função de conveniência chamada `Run`. `Run` pega um endereço de string idêntico para [http.ListenAndServe](http://golang.org/pkg/net/http#ListenAndServe).
~~~ go
n := negroni.Classic()
// ...
log.Fatal(http.ListenAndServe(":8080", n))
~~~
## Middleware para Rotas Específicas
Se você tem um grupo de rota com rotas que precisam ser executadas por um middleware específico, pode simplesmente criar uma nova instância de Negroni e usar no seu Manipular de rota.
~~~ go
router := mux.NewRouter()
adminRoutes := mux.NewRouter()
// add admin routes here
// Criar um middleware negroni para admin
router.Handle("/admin", negroni.New(
Middleware1,
Middleware2,
negroni.Wrap(adminRoutes),
))
~~~
## Middleware de Terceiros
Aqui está uma lista atual de Middleware Compatíveis com Negroni. Sinta se livre para mandar um PR vinculando seu middleware if construiu um:
| Middleware | Autor | Descrição |
| -----------|--------|-------------|
| [Graceful](https://github.com/stretchr/graceful) | [Tyler Bunnell](https://github.com/tylerb) | Graceful HTTP Shutdown |
| [secure](https://github.com/unrolled/secure) | [Cory Jacobsen](https://github.com/unrolled) | Implementa rapidamente itens de segurança.|
| [binding](https://github.com/mholt/binding) | [Matt Holt](https://github.com/mholt) | Handler para mapeamento/validação de um request a estrutura. |
| [logrus](https://github.com/meatballhat/negroni-logrus) | [Dan Buch](https://github.com/meatballhat) | Logrus-based logger |
| [render](https://github.com/unrolled/render) | [Cory Jacobsen](https://github.com/unrolled) | Pacote para renderizar JSON, XML, e templates HTML. |
| [gorelic](https://github.com/jingweno/negroni-gorelic) | [Jingwen Owen Ou](https://github.com/jingweno) | New Relic agent for Go runtime |
| [gzip](https://github.com/phyber/negroni-gzip) | [phyber](https://github.com/phyber) | Handler para adicionar compreção gzip para as requisições |
| [oauth2](https://github.com/goincremental/negroni-oauth2) | [David Bochenski](https://github.com/bochenski) | Handler que prove sistema de login OAuth 2.0 para aplicações Martini. Google Sign-in, Facebook Connect e Github login são suportados. |
| [sessions](https://github.com/goincremental/negroni-sessions) | [David Bochenski](https://github.com/bochenski) | Handler que provê o serviço de sessão. |
| [permissions](https://github.com/xyproto/permissions) | [Alexander Rødseth](https://github.com/xyproto) | Cookies, usuários e permissões. |
| [onthefly](https://github.com/xyproto/onthefly) | [Alexander Rødseth](https://github.com/xyproto) | Pacote para gerar TinySVG, HTML e CSS em tempo real. |
## Exemplos
[Alexander Rødseth](https://github.com/xyproto) criou [mooseware](https://github.com/xyproto/mooseware), uma estrutura para escrever um handler middleware Negroni.
## Servidor com autoreload?
[gin](https://github.com/codegangsta/gin) e [fresh](https://github.com/pilu/fresh) são aplicativos para autoreload do Negroni.
## Sobre
Negroni é obsessivamente desenhado por ninguém menos que [Code Gangsta](http://codegangsta.io/)
CoreOS Project
Copyright 2014 CoreOS, Inc
This product includes software developed at CoreOS, Inc.
(http://www.coreos.com/).
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package alarm manages health status alarms in etcd.
package alarm
import (
"sync"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"github.com/coreos/etcd/pkg/types"
"github.com/coreos/etcd/storage/backend"
"github.com/coreos/pkg/capnslog"
)
var (
alarmBucketName = []byte("alarm")
plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "alarm")
)
type BackendGetter interface {
Backend() backend.Backend
}
type alarmSet map[types.ID]*pb.AlarmMember
// AlarmStore persists alarms to the backend.
type AlarmStore struct {
mu sync.Mutex
types map[pb.AlarmType]alarmSet
bg BackendGetter
}
func NewAlarmStore(bg BackendGetter) (*AlarmStore, error) {
ret := &AlarmStore{types: make(map[pb.AlarmType]alarmSet), bg: bg}
err := ret.restore()
return ret, err
}
func (a *AlarmStore) Activate(id types.ID, at pb.AlarmType) *pb.AlarmMember {
a.mu.Lock()
defer a.mu.Unlock()
newAlarm := &pb.AlarmMember{MemberID: uint64(id), Alarm: at}
if m := a.addToMap(newAlarm); m != newAlarm {
return m
}
v, err := newAlarm.Marshal()
if err != nil {
plog.Panicf("failed to marshal alarm member")
}
b := a.bg.Backend()
b.BatchTx().Lock()
b.BatchTx().UnsafePut(alarmBucketName, v, nil)
b.BatchTx().Unlock()
return newAlarm
}
func (a *AlarmStore) Deactivate(id types.ID, at pb.AlarmType) *pb.AlarmMember {
a.mu.Lock()
defer a.mu.Unlock()
t := a.types[at]
if t == nil {
t = make(alarmSet)
a.types[at] = t
}
m := t[id]
if m == nil {
return nil
}
delete(t, id)
v, err := m.Marshal()
if err != nil {
plog.Panicf("failed to marshal alarm member")
}
b := a.bg.Backend()
b.BatchTx().Lock()
b.BatchTx().UnsafeDelete(alarmBucketName, v)
b.BatchTx().Unlock()
return m
}
func (a *AlarmStore) Get(at pb.AlarmType) (ret []*pb.AlarmMember) {
a.mu.Lock()
defer a.mu.Unlock()
if at == pb.AlarmType_NONE {
for _, t := range a.types {
for _, m := range t {
ret = append(ret, m)
}
}
return ret
}
for _, m := range a.types[at] {
ret = append(ret, m)
}
return ret
}
func (a *AlarmStore) restore() error {
b := a.bg.Backend()
tx := b.BatchTx()
tx.Lock()
tx.UnsafeCreateBucket(alarmBucketName)
err := tx.UnsafeForEach(alarmBucketName, func(k, v []byte) error {
var m pb.AlarmMember
if err := m.Unmarshal(k); err != nil {
return err
}
a.addToMap(&m)
return nil
})
tx.Unlock()
b.ForceCommit()
return err
}
func (a *AlarmStore) addToMap(newAlarm *pb.AlarmMember) *pb.AlarmMember {
t := a.types[newAlarm.Alarm]
if t == nil {
t = make(alarmSet)
a.types[newAlarm.Alarm] = t
}
m := t[types.ID(newAlarm.MemberID)]
if m != nil {
return m
}
t[types.ID(newAlarm.MemberID)] = newAlarm
return newAlarm
}
// Copyright 2016 Nippon Telegraph and Telephone Corporation.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package auth
import (
"errors"
"github.com/coreos/etcd/auth/authpb"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"github.com/coreos/etcd/storage/backend"
"github.com/coreos/pkg/capnslog"
"golang.org/x/crypto/bcrypt"
)
var (
enableFlagKey = []byte("authEnabled")
authBucketName = []byte("auth")
authUsersBucketName = []byte("authUsers")
authRolesBucketName = []byte("authRoles")
plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "auth")
ErrUserAlreadyExist = errors.New("auth: user already exists")
ErrUserNotFound = errors.New("auth: user not found")
ErrRoleAlreadyExist = errors.New("auth: role already exists")
)
type AuthStore interface {
// AuthEnable() turns on the authentication feature
AuthEnable()
// Recover recovers the state of auth store from the given backend
Recover(b backend.Backend)
// UserAdd adds a new user
UserAdd(r *pb.AuthUserAddRequest) (*pb.AuthUserAddResponse, error)
// UserDelete deletes a user
UserDelete(r *pb.AuthUserDeleteRequest) (*pb.AuthUserDeleteResponse, error)
// UserChangePassword changes a password of a user
UserChangePassword(r *pb.AuthUserChangePasswordRequest) (*pb.AuthUserChangePasswordResponse, error)
// RoleAdd adds a new role
RoleAdd(r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse, error)
}
type authStore struct {
be backend.Backend
}
func (as *authStore) AuthEnable() {
value := []byte{1}
b := as.be
tx := b.BatchTx()
tx.Lock()
tx.UnsafePut(authBucketName, enableFlagKey, value)
tx.Unlock()
b.ForceCommit()
plog.Noticef("Authentication enabled")
}
func (as *authStore) Recover(be backend.Backend) {
as.be = be
// TODO(mitake): recovery process
}
func (as *authStore) UserAdd(r *pb.AuthUserAddRequest) (*pb.AuthUserAddResponse, error) {
plog.Noticef("adding a new user: %s", r.Name)
hashed, err := bcrypt.GenerateFromPassword([]byte(r.Password), bcrypt.DefaultCost)
if err != nil {
plog.Errorf("failed to hash password: %s", err)
return nil, err
}
tx := as.be.BatchTx()
tx.Lock()
defer tx.Unlock()
_, vs := tx.UnsafeRange(authUsersBucketName, []byte(r.Name), nil, 0)
if len(vs) != 0 {
return &pb.AuthUserAddResponse{}, ErrUserAlreadyExist
}
newUser := authpb.User{
Name: []byte(r.Name),
Password: hashed,
}
marshaledUser, merr := newUser.Marshal()
if merr != nil {
plog.Errorf("failed to marshal a new user data: %s", merr)
return nil, merr
}
tx.UnsafePut(authUsersBucketName, []byte(r.Name), marshaledUser)
plog.Noticef("added a new user: %s", r.Name)
return &pb.AuthUserAddResponse{}, nil
}
func (as *authStore) UserDelete(r *pb.AuthUserDeleteRequest) (*pb.AuthUserDeleteResponse, error) {
tx := as.be.BatchTx()
tx.Lock()
defer tx.Unlock()
_, vs := tx.UnsafeRange(authUsersBucketName, []byte(r.Name), nil, 0)
if len(vs) != 1 {
return &pb.AuthUserDeleteResponse{}, ErrUserNotFound
}
tx.UnsafeDelete(authUsersBucketName, []byte(r.Name))
plog.Noticef("deleted a user: %s", r.Name)
return &pb.AuthUserDeleteResponse{}, nil
}
func (as *authStore) UserChangePassword(r *pb.AuthUserChangePasswordRequest) (*pb.AuthUserChangePasswordResponse, error) {
// TODO(mitake): measure the cost of bcrypt.GenerateFromPassword()
// If the cost is too high, we should move the encryption to outside of the raft
hashed, err := bcrypt.GenerateFromPassword([]byte(r.Password), bcrypt.DefaultCost)
if err != nil {
plog.Errorf("failed to hash password: %s", err)
return nil, err
}
tx := as.be.BatchTx()
tx.Lock()
defer tx.Unlock()
_, vs := tx.UnsafeRange(authUsersBucketName, []byte(r.Name), nil, 0)
if len(vs) != 1 {
return &pb.AuthUserChangePasswordResponse{}, ErrUserNotFound
}
updatedUser := authpb.User{
Name: []byte(r.Name),
Password: hashed,
}
marshaledUser, merr := updatedUser.Marshal()
if merr != nil {
plog.Errorf("failed to marshal a new user data: %s", merr)
return nil, merr
}
tx.UnsafePut(authUsersBucketName, []byte(r.Name), marshaledUser)
plog.Noticef("changed a password of a user: %s", r.Name)
return &pb.AuthUserChangePasswordResponse{}, nil
}
func (as *authStore) RoleAdd(r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse, error) {
tx := as.be.BatchTx()
tx.Lock()
defer tx.Unlock()
_, vs := tx.UnsafeRange(authRolesBucketName, []byte(r.Name), nil, 0)
if len(vs) != 0 {
return nil, ErrRoleAlreadyExist
}
newRole := &authpb.Role{
Name: []byte(r.Name),
}
marshaledRole, err := newRole.Marshal()
if err != nil {
return nil, err
}
tx.UnsafePut(authRolesBucketName, []byte(r.Name), marshaledRole)
plog.Noticef("Role %s is created", r.Name)
return &pb.AuthRoleAddResponse{}, nil
}
func NewAuthStore(be backend.Backend) *authStore {
tx := be.BatchTx()
tx.Lock()
tx.UnsafeCreateBucket(authBucketName)
tx.UnsafeCreateBucket(authUsersBucketName)
tx.UnsafeCreateBucket(authRolesBucketName)
tx.Unlock()
be.ForceCommit()
return &authStore{
be: be,
}
}
# etcd/client
etcd/client is the Go client library for etcd.
[![GoDoc](https://godoc.org/github.com/coreos/etcd/client?status.png)](https://godoc.org/github.com/coreos/etcd/client)
etcd uses go's `vendor` directory to manage external dependencies. If `client` is imported
outside of etcd, simply copy `client` to the `vendor` directory or use tools like godep to
manage your own dependency, as in [vendor directories](https://golang.org/cmd/go/#hdr-Vendor_Directories).
For more detail, please read [Go vendor design](https://golang.org/s/go15vendor).
## Install
```bash
go get github.com/coreos/etcd/client
```
## Usage
```go
package main
import (
"log"
"time"
"golang.org/x/net/context"
"github.com/coreos/etcd/client"
)
func main() {
cfg := client.Config{
Endpoints: []string{"http://127.0.0.1:2379"},
Transport: client.DefaultTransport,
// set timeout per request to fail fast when the target endpoint is unavailable
HeaderTimeoutPerRequest: time.Second,
}
c, err := client.New(cfg)
if err != nil {
log.Fatal(err)
}
kapi := client.NewKeysAPI(c)
// set "/foo" key with "bar" value
log.Print("Setting '/foo' key with 'bar' value")
resp, err := kapi.Set(context.Background(), "/foo", "bar", nil)
if err != nil {
log.Fatal(err)
} else {
// print common key info
log.Printf("Set is done. Metadata is %q\n", resp)
}
// get "/foo" key's value
log.Print("Getting '/foo' key value")
resp, err = kapi.Get(context.Background(), "/foo", nil)
if err != nil {
log.Fatal(err)
} else {
// print common key info
log.Printf("Get is done. Metadata is %q\n", resp)
// print value
log.Printf("%q key has %q value\n", resp.Node.Key, resp.Node.Value)
}
}
```
## Error Handling
etcd client might return three types of errors.
- context error
Each API call has its first parameter as `context`. A context can be canceled or have an attached deadline. If the context is canceled or reaches its deadline, the responding context error will be returned no matter what internal errors the API call has already encountered.
- cluster error
Each API call tries to send request to the cluster endpoints one by one until it successfully gets a response. If a requests to an endpoint fails, due to exceeding per request timeout or connection issues, the error will be added into a list of errors. If all possible endpoints fail, a cluster error that includes all encountered errors will be returned.
- response error
If the response gets from the cluster is invalid, a plain string error will be returned. For example, it might be a invalid JSON error.
Here is the example code to handle client errors:
```go
cfg := client.Config{Endpoints: []string{"http://etcd1:2379","http://etcd2:2379","http://etcd3:2379"}}
c, err := client.New(cfg)
if err != nil {
log.Fatal(err)
}
kapi := client.NewKeysAPI(c)
resp, err := kapi.Set(ctx, "test", "bar", nil)
if err != nil {
if err == context.Canceled {
// ctx is canceled by another routine
} else if err == context.DeadlineExceeded {
// ctx is attached with a deadline and it exceeded
} else if cerr, ok := err.(*client.ClusterError); ok {
// process (cerr.Errors)
} else {
// bad cluster endpoints, which are not etcd servers
}
}
```
## Caveat
1. etcd/client prefers to use the same endpoint as long as the endpoint continues to work well. This saves socket resources, and improves efficiency for both client and server side. This preference doesn't remove consistency from the data consumed by the client because data replicated to each etcd member has already passed through the consensus process.
2. etcd/client does round-robin rotation on other available endpoints if the preferred endpoint isn't functioning properly. For example, if the member that etcd/client connects to is hard killed, etcd/client will fail on the first attempt with the killed member, and succeed on the second attempt with another member. If it fails to talk to all available endpoints, it will return all errors happened.
3. Default etcd/client cannot handle the case that the remote server is SIGSTOPed now. TCP keepalive mechanism doesn't help in this scenario because operating system may still send TCP keep-alive packets. Over time we'd like to improve this functionality, but solving this issue isn't high priority because a real-life case in which a server is stopped, but the connection is kept alive, hasn't been brought to our attention.
4. etcd/client cannot detect whether the member in use is healthy when doing read requests. If the member is isolated from the cluster, etcd/client may retrieve outdated data. As a workaround, users could monitor experimental /health endpoint for member healthy information. We are improving it at [#3265](https://github.com/coreos/etcd/issues/3265).
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import (
"bytes"
"encoding/json"
"net/http"
"net/url"
"golang.org/x/net/context"
)
type Role struct {
Role string `json:"role"`
Permissions Permissions `json:"permissions"`
Grant *Permissions `json:"grant,omitempty"`
Revoke *Permissions `json:"revoke,omitempty"`
}
type Permissions struct {
KV rwPermission `json:"kv"`
}
type rwPermission struct {
Read []string `json:"read"`
Write []string `json:"write"`
}
type PermissionType int
const (
ReadPermission PermissionType = iota
WritePermission
ReadWritePermission
)
// NewAuthRoleAPI constructs a new AuthRoleAPI that uses HTTP to
// interact with etcd's role creation and modification features.
func NewAuthRoleAPI(c Client) AuthRoleAPI {
return &httpAuthRoleAPI{
client: c,
}
}
type AuthRoleAPI interface {
// AddRole adds a role.
AddRole(ctx context.Context, role string) error
// RemoveRole removes a role.
RemoveRole(ctx context.Context, role string) error
// GetRole retrieves role details.
GetRole(ctx context.Context, role string) (*Role, error)
// GrantRoleKV grants a role some permission prefixes for the KV store.
GrantRoleKV(ctx context.Context, role string, prefixes []string, permType PermissionType) (*Role, error)
// RevokeRoleKV revokes some permission prefixes for a role on the KV store.
RevokeRoleKV(ctx context.Context, role string, prefixes []string, permType PermissionType) (*Role, error)
// ListRoles lists roles.
ListRoles(ctx context.Context) ([]string, error)
}
type httpAuthRoleAPI struct {
client httpClient
}
type authRoleAPIAction struct {
verb string
name string
role *Role
}
type authRoleAPIList struct{}
func (list *authRoleAPIList) HTTPRequest(ep url.URL) *http.Request {
u := v2AuthURL(ep, "roles", "")
req, _ := http.NewRequest("GET", u.String(), nil)
req.Header.Set("Content-Type", "application/json")
return req
}
func (l *authRoleAPIAction) HTTPRequest(ep url.URL) *http.Request {
u := v2AuthURL(ep, "roles", l.name)
if l.role == nil {
req, _ := http.NewRequest(l.verb, u.String(), nil)
return req
}
b, err := json.Marshal(l.role)
if err != nil {
panic(err)
}
body := bytes.NewReader(b)
req, _ := http.NewRequest(l.verb, u.String(), body)
req.Header.Set("Content-Type", "application/json")
return req
}
func (r *httpAuthRoleAPI) ListRoles(ctx context.Context) ([]string, error) {
resp, body, err := r.client.Do(ctx, &authRoleAPIList{})
if err != nil {
return nil, err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
return nil, err
}
var roleList struct {
Roles []Role `json:"roles"`
}
if err = json.Unmarshal(body, &roleList); err != nil {
return nil, err
}
ret := make([]string, 0, len(roleList.Roles))
for _, r := range roleList.Roles {
ret = append(ret, r.Role)
}
return ret, nil
}
func (r *httpAuthRoleAPI) AddRole(ctx context.Context, rolename string) error {
role := &Role{
Role: rolename,
}
return r.addRemoveRole(ctx, &authRoleAPIAction{
verb: "PUT",
name: rolename,
role: role,
})
}
func (r *httpAuthRoleAPI) RemoveRole(ctx context.Context, rolename string) error {
return r.addRemoveRole(ctx, &authRoleAPIAction{
verb: "DELETE",
name: rolename,
})
}
func (r *httpAuthRoleAPI) addRemoveRole(ctx context.Context, req *authRoleAPIAction) error {
resp, body, err := r.client.Do(ctx, req)
if err != nil {
return err
}
if err := assertStatusCode(resp.StatusCode, http.StatusOK, http.StatusCreated); err != nil {
var sec authError
err := json.Unmarshal(body, &sec)
if err != nil {
return err
}
return sec
}
return nil
}
func (r *httpAuthRoleAPI) GetRole(ctx context.Context, rolename string) (*Role, error) {
return r.modRole(ctx, &authRoleAPIAction{
verb: "GET",
name: rolename,
})
}
func buildRWPermission(prefixes []string, permType PermissionType) rwPermission {
var out rwPermission
switch permType {
case ReadPermission:
out.Read = prefixes
case WritePermission:
out.Write = prefixes
case ReadWritePermission:
out.Read = prefixes
out.Write = prefixes
}
return out
}
func (r *httpAuthRoleAPI) GrantRoleKV(ctx context.Context, rolename string, prefixes []string, permType PermissionType) (*Role, error) {
rwp := buildRWPermission(prefixes, permType)
role := &Role{
Role: rolename,
Grant: &Permissions{
KV: rwp,
},
}
return r.modRole(ctx, &authRoleAPIAction{
verb: "PUT",
name: rolename,
role: role,
})
}
func (r *httpAuthRoleAPI) RevokeRoleKV(ctx context.Context, rolename string, prefixes []string, permType PermissionType) (*Role, error) {
rwp := buildRWPermission(prefixes, permType)
role := &Role{
Role: rolename,
Revoke: &Permissions{
KV: rwp,
},
}
return r.modRole(ctx, &authRoleAPIAction{
verb: "PUT",
name: rolename,
role: role,
})
}
func (r *httpAuthRoleAPI) modRole(ctx context.Context, req *authRoleAPIAction) (*Role, error) {
resp, body, err := r.client.Do(ctx, req)
if err != nil {
return nil, err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
var sec authError
err = json.Unmarshal(body, &sec)
if err != nil {
return nil, err
}
return nil, sec
}
var role Role
if err = json.Unmarshal(body, &role); err != nil {
return nil, err
}
return &role, nil
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import (
"bytes"
"encoding/json"
"net/http"
"net/url"
"path"
"golang.org/x/net/context"
)
var (
defaultV2AuthPrefix = "/v2/auth"
)
type User struct {
User string `json:"user"`
Password string `json:"password,omitempty"`
Roles []string `json:"roles"`
Grant []string `json:"grant,omitempty"`
Revoke []string `json:"revoke,omitempty"`
}
type UserRoles struct {
User string `json:"user"`
Roles []Role `json:"roles"`
}
func v2AuthURL(ep url.URL, action string, name string) *url.URL {
if name != "" {
ep.Path = path.Join(ep.Path, defaultV2AuthPrefix, action, name)
return &ep
}
ep.Path = path.Join(ep.Path, defaultV2AuthPrefix, action)
return &ep
}
// NewAuthAPI constructs a new AuthAPI that uses HTTP to
// interact with etcd's general auth features.
func NewAuthAPI(c Client) AuthAPI {
return &httpAuthAPI{
client: c,
}
}
type AuthAPI interface {
// Enable auth.
Enable(ctx context.Context) error
// Disable auth.
Disable(ctx context.Context) error
}
type httpAuthAPI struct {
client httpClient
}
func (s *httpAuthAPI) Enable(ctx context.Context) error {
return s.enableDisable(ctx, &authAPIAction{"PUT"})
}
func (s *httpAuthAPI) Disable(ctx context.Context) error {
return s.enableDisable(ctx, &authAPIAction{"DELETE"})
}
func (s *httpAuthAPI) enableDisable(ctx context.Context, req httpAction) error {
resp, body, err := s.client.Do(ctx, req)
if err != nil {
return err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK, http.StatusCreated); err != nil {
var sec authError
err = json.Unmarshal(body, &sec)
if err != nil {
return err
}
return sec
}
return nil
}
type authAPIAction struct {
verb string
}
func (l *authAPIAction) HTTPRequest(ep url.URL) *http.Request {
u := v2AuthURL(ep, "enable", "")
req, _ := http.NewRequest(l.verb, u.String(), nil)
return req
}
type authError struct {
Message string `json:"message"`
Code int `json:"-"`
}
func (e authError) Error() string {
return e.Message
}
// NewAuthUserAPI constructs a new AuthUserAPI that uses HTTP to
// interact with etcd's user creation and modification features.
func NewAuthUserAPI(c Client) AuthUserAPI {
return &httpAuthUserAPI{
client: c,
}
}
type AuthUserAPI interface {
// AddUser adds a user.
AddUser(ctx context.Context, username string, password string) error
// RemoveUser removes a user.
RemoveUser(ctx context.Context, username string) error
// GetUser retrieves user details.
GetUser(ctx context.Context, username string) (*User, error)
// GrantUser grants a user some permission roles.
GrantUser(ctx context.Context, username string, roles []string) (*User, error)
// RevokeUser revokes some permission roles from a user.
RevokeUser(ctx context.Context, username string, roles []string) (*User, error)
// ChangePassword changes the user's password.
ChangePassword(ctx context.Context, username string, password string) (*User, error)
// ListUsers lists the users.
ListUsers(ctx context.Context) ([]string, error)
}
type httpAuthUserAPI struct {
client httpClient
}
type authUserAPIAction struct {
verb string
username string
user *User
}
type authUserAPIList struct{}
func (list *authUserAPIList) HTTPRequest(ep url.URL) *http.Request {
u := v2AuthURL(ep, "users", "")
req, _ := http.NewRequest("GET", u.String(), nil)
req.Header.Set("Content-Type", "application/json")
return req
}
func (l *authUserAPIAction) HTTPRequest(ep url.URL) *http.Request {
u := v2AuthURL(ep, "users", l.username)
if l.user == nil {
req, _ := http.NewRequest(l.verb, u.String(), nil)
return req
}
b, err := json.Marshal(l.user)
if err != nil {
panic(err)
}
body := bytes.NewReader(b)
req, _ := http.NewRequest(l.verb, u.String(), body)
req.Header.Set("Content-Type", "application/json")
return req
}
func (u *httpAuthUserAPI) ListUsers(ctx context.Context) ([]string, error) {
resp, body, err := u.client.Do(ctx, &authUserAPIList{})
if err != nil {
return nil, err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
var sec authError
err = json.Unmarshal(body, &sec)
if err != nil {
return nil, err
}
return nil, sec
}
var userList struct {
Users []User `json:"users"`
}
if err = json.Unmarshal(body, &userList); err != nil {
return nil, err
}
ret := make([]string, 0, len(userList.Users))
for _, u := range userList.Users {
ret = append(ret, u.User)
}
return ret, nil
}
func (u *httpAuthUserAPI) AddUser(ctx context.Context, username string, password string) error {
user := &User{
User: username,
Password: password,
}
return u.addRemoveUser(ctx, &authUserAPIAction{
verb: "PUT",
username: username,
user: user,
})
}
func (u *httpAuthUserAPI) RemoveUser(ctx context.Context, username string) error {
return u.addRemoveUser(ctx, &authUserAPIAction{
verb: "DELETE",
username: username,
})
}
func (u *httpAuthUserAPI) addRemoveUser(ctx context.Context, req *authUserAPIAction) error {
resp, body, err := u.client.Do(ctx, req)
if err != nil {
return err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK, http.StatusCreated); err != nil {
var sec authError
err = json.Unmarshal(body, &sec)
if err != nil {
return err
}
return sec
}
return nil
}
func (u *httpAuthUserAPI) GetUser(ctx context.Context, username string) (*User, error) {
return u.modUser(ctx, &authUserAPIAction{
verb: "GET",
username: username,
})
}
func (u *httpAuthUserAPI) GrantUser(ctx context.Context, username string, roles []string) (*User, error) {
user := &User{
User: username,
Grant: roles,
}
return u.modUser(ctx, &authUserAPIAction{
verb: "PUT",
username: username,
user: user,
})
}
func (u *httpAuthUserAPI) RevokeUser(ctx context.Context, username string, roles []string) (*User, error) {
user := &User{
User: username,
Revoke: roles,
}
return u.modUser(ctx, &authUserAPIAction{
verb: "PUT",
username: username,
user: user,
})
}
func (u *httpAuthUserAPI) ChangePassword(ctx context.Context, username string, password string) (*User, error) {
user := &User{
User: username,
Password: password,
}
return u.modUser(ctx, &authUserAPIAction{
verb: "PUT",
username: username,
user: user,
})
}
func (u *httpAuthUserAPI) modUser(ctx context.Context, req *authUserAPIAction) (*User, error) {
resp, body, err := u.client.Do(ctx, req)
if err != nil {
return nil, err
}
if err = assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
var sec authError
err = json.Unmarshal(body, &sec)
if err != nil {
return nil, err
}
return nil, sec
}
var user User
if err = json.Unmarshal(body, &user); err != nil {
var userR UserRoles
if urerr := json.Unmarshal(body, &userR); urerr != nil {
return nil, err
}
user.User = userR.User
for _, r := range userR.Roles {
user.Roles = append(user.Roles, r.Role)
}
}
return &user, nil
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import "fmt"
type ClusterError struct {
Errors []error
}
func (ce *ClusterError) Error() string {
return ErrClusterUnavailable.Error()
}
func (ce *ClusterError) Detail() string {
s := ""
for i, e := range ce.Errors {
s += fmt.Sprintf("error #%d: %s\n", i, e)
}
return s
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import (
"bytes"
"fmt"
"io/ioutil"
"net/http"
"os"
)
var (
cURLDebug = false
)
func EnablecURLDebug() {
cURLDebug = true
}
func DisablecURLDebug() {
cURLDebug = false
}
// printcURL prints the cURL equivalent request to stderr.
// It returns an error if the body of the request cannot
// be read.
// The caller MUST cancel the request if there is an error.
func printcURL(req *http.Request) error {
if !cURLDebug {
return nil
}
var (
command string
b []byte
err error
)
if req.URL != nil {
command = fmt.Sprintf("curl -X %s %s", req.Method, req.URL.String())
}
if req.Body != nil {
b, err = ioutil.ReadAll(req.Body)
if err != nil {
return err
}
command += fmt.Sprintf(" -d %q", string(b))
}
fmt.Fprintf(os.Stderr, "cURL Command: %s\n", command)
// reset body
body := bytes.NewBuffer(b)
req.Body = ioutil.NopCloser(body)
return nil
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
// Discoverer is an interface that wraps the Discover method.
type Discoverer interface {
// Discover looks up the etcd servers for the domain.
Discover(domain string) ([]string, error)
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/*
Package client provides bindings for the etcd APIs.
Create a Config and exchange it for a Client:
import (
"net/http"
"github.com/coreos/etcd/client"
"golang.org/x/net/context"
)
cfg := client.Config{
Endpoints: []string{"http://127.0.0.1:2379"},
Transport: DefaultTransport,
}
c, err := client.New(cfg)
if err != nil {
// handle error
}
Clients are safe for concurrent use by multiple goroutines.
Create a KeysAPI using the Client, then use it to interact with etcd:
kAPI := client.NewKeysAPI(c)
// create a new key /foo with the value "bar"
_, err = kAPI.Create(context.Background(), "/foo", "bar")
if err != nil {
// handle error
}
// delete the newly created key only if the value is still "bar"
_, err = kAPI.Delete(context.Background(), "/foo", &DeleteOptions{PrevValue: "bar"})
if err != nil {
// handle error
}
Use a custom context to set timeouts on your operations:
import "time"
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
// set a new key, ignoring it's previous state
_, err := kAPI.Set(ctx, "/ping", "pong", nil)
if err != nil {
if err == context.DeadlineExceeded {
// request took longer than 5s
} else {
// handle error
}
}
*/
package client
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import (
"bytes"
"encoding/json"
"fmt"
"net/http"
"net/url"
"path"
"golang.org/x/net/context"
"github.com/coreos/etcd/pkg/types"
)
var (
defaultV2MembersPrefix = "/v2/members"
defaultLeaderSuffix = "/leader"
)
type Member struct {
// ID is the unique identifier of this Member.
ID string `json:"id"`
// Name is a human-readable, non-unique identifier of this Member.
Name string `json:"name"`
// PeerURLs represents the HTTP(S) endpoints this Member uses to
// participate in etcd's consensus protocol.
PeerURLs []string `json:"peerURLs"`
// ClientURLs represents the HTTP(S) endpoints on which this Member
// serves it's client-facing APIs.
ClientURLs []string `json:"clientURLs"`
}
type memberCollection []Member
func (c *memberCollection) UnmarshalJSON(data []byte) error {
d := struct {
Members []Member
}{}
if err := json.Unmarshal(data, &d); err != nil {
return err
}
if d.Members == nil {
*c = make([]Member, 0)
return nil
}
*c = d.Members
return nil
}
type memberCreateOrUpdateRequest struct {
PeerURLs types.URLs
}
func (m *memberCreateOrUpdateRequest) MarshalJSON() ([]byte, error) {
s := struct {
PeerURLs []string `json:"peerURLs"`
}{
PeerURLs: make([]string, len(m.PeerURLs)),
}
for i, u := range m.PeerURLs {
s.PeerURLs[i] = u.String()
}
return json.Marshal(&s)
}
// NewMembersAPI constructs a new MembersAPI that uses HTTP to
// interact with etcd's membership API.
func NewMembersAPI(c Client) MembersAPI {
return &httpMembersAPI{
client: c,
}
}
type MembersAPI interface {
// List enumerates the current cluster membership.
List(ctx context.Context) ([]Member, error)
// Add instructs etcd to accept a new Member into the cluster.
Add(ctx context.Context, peerURL string) (*Member, error)
// Remove demotes an existing Member out of the cluster.
Remove(ctx context.Context, mID string) error
// Update instructs etcd to update an existing Member in the cluster.
Update(ctx context.Context, mID string, peerURLs []string) error
// Leader gets current leader of the cluster
Leader(ctx context.Context) (*Member, error)
}
type httpMembersAPI struct {
client httpClient
}
func (m *httpMembersAPI) List(ctx context.Context) ([]Member, error) {
req := &membersAPIActionList{}
resp, body, err := m.client.Do(ctx, req)
if err != nil {
return nil, err
}
if err := assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
return nil, err
}
var mCollection memberCollection
if err := json.Unmarshal(body, &mCollection); err != nil {
return nil, err
}
return []Member(mCollection), nil
}
func (m *httpMembersAPI) Add(ctx context.Context, peerURL string) (*Member, error) {
urls, err := types.NewURLs([]string{peerURL})
if err != nil {
return nil, err
}
req := &membersAPIActionAdd{peerURLs: urls}
resp, body, err := m.client.Do(ctx, req)
if err != nil {
return nil, err
}
if err := assertStatusCode(resp.StatusCode, http.StatusCreated, http.StatusConflict); err != nil {
return nil, err
}
if resp.StatusCode != http.StatusCreated {
var merr membersError
if err := json.Unmarshal(body, &merr); err != nil {
return nil, err
}
return nil, merr
}
var memb Member
if err := json.Unmarshal(body, &memb); err != nil {
return nil, err
}
return &memb, nil
}
func (m *httpMembersAPI) Update(ctx context.Context, memberID string, peerURLs []string) error {
urls, err := types.NewURLs(peerURLs)
if err != nil {
return err
}
req := &membersAPIActionUpdate{peerURLs: urls, memberID: memberID}
resp, body, err := m.client.Do(ctx, req)
if err != nil {
return err
}
if err := assertStatusCode(resp.StatusCode, http.StatusNoContent, http.StatusNotFound, http.StatusConflict); err != nil {
return err
}
if resp.StatusCode != http.StatusNoContent {
var merr membersError
if err := json.Unmarshal(body, &merr); err != nil {
return err
}
return merr
}
return nil
}
func (m *httpMembersAPI) Remove(ctx context.Context, memberID string) error {
req := &membersAPIActionRemove{memberID: memberID}
resp, _, err := m.client.Do(ctx, req)
if err != nil {
return err
}
return assertStatusCode(resp.StatusCode, http.StatusNoContent, http.StatusGone)
}
func (m *httpMembersAPI) Leader(ctx context.Context) (*Member, error) {
req := &membersAPIActionLeader{}
resp, body, err := m.client.Do(ctx, req)
if err != nil {
return nil, err
}
if err := assertStatusCode(resp.StatusCode, http.StatusOK); err != nil {
return nil, err
}
var leader Member
if err := json.Unmarshal(body, &leader); err != nil {
return nil, err
}
return &leader, nil
}
type membersAPIActionList struct{}
func (l *membersAPIActionList) HTTPRequest(ep url.URL) *http.Request {
u := v2MembersURL(ep)
req, _ := http.NewRequest("GET", u.String(), nil)
return req
}
type membersAPIActionRemove struct {
memberID string
}
func (d *membersAPIActionRemove) HTTPRequest(ep url.URL) *http.Request {
u := v2MembersURL(ep)
u.Path = path.Join(u.Path, d.memberID)
req, _ := http.NewRequest("DELETE", u.String(), nil)
return req
}
type membersAPIActionAdd struct {
peerURLs types.URLs
}
func (a *membersAPIActionAdd) HTTPRequest(ep url.URL) *http.Request {
u := v2MembersURL(ep)
m := memberCreateOrUpdateRequest{PeerURLs: a.peerURLs}
b, _ := json.Marshal(&m)
req, _ := http.NewRequest("POST", u.String(), bytes.NewReader(b))
req.Header.Set("Content-Type", "application/json")
return req
}
type membersAPIActionUpdate struct {
memberID string
peerURLs types.URLs
}
func (a *membersAPIActionUpdate) HTTPRequest(ep url.URL) *http.Request {
u := v2MembersURL(ep)
m := memberCreateOrUpdateRequest{PeerURLs: a.peerURLs}
u.Path = path.Join(u.Path, a.memberID)
b, _ := json.Marshal(&m)
req, _ := http.NewRequest("PUT", u.String(), bytes.NewReader(b))
req.Header.Set("Content-Type", "application/json")
return req
}
func assertStatusCode(got int, want ...int) (err error) {
for _, w := range want {
if w == got {
return nil
}
}
return fmt.Errorf("unexpected status code %d", got)
}
type membersAPIActionLeader struct{}
func (l *membersAPIActionLeader) HTTPRequest(ep url.URL) *http.Request {
u := v2MembersURL(ep)
u.Path = path.Join(u.Path, defaultLeaderSuffix)
req, _ := http.NewRequest("GET", u.String(), nil)
return req
}
// v2MembersURL add the necessary path to the provided endpoint
// to route requests to the default v2 members API.
func v2MembersURL(ep url.URL) *url.URL {
ep.Path = path.Join(ep.Path, defaultV2MembersPrefix)
return &ep
}
type membersError struct {
Message string `json:"message"`
Code int `json:"-"`
}
func (e membersError) Error() string {
return e.Message
}
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
import (
"fmt"
"net"
"net/url"
)
var (
// indirection for testing
lookupSRV = net.LookupSRV
)
type srvDiscover struct{}
// NewSRVDiscover constructs a new Discoverer that uses the stdlib to lookup SRV records.
func NewSRVDiscover() Discoverer {
return &srvDiscover{}
}
// Discover looks up the etcd servers for the domain.
func (d *srvDiscover) Discover(domain string) ([]string, error) {
var urls []*url.URL
updateURLs := func(service, scheme string) error {
_, addrs, err := lookupSRV(service, "tcp", domain)
if err != nil {
return err
}
for _, srv := range addrs {
urls = append(urls, &url.URL{
Scheme: scheme,
Host: net.JoinHostPort(srv.Target, fmt.Sprintf("%d", srv.Port)),
})
}
return nil
}
errHTTPS := updateURLs("etcd-client-ssl", "https")
errHTTP := updateURLs("etcd-client", "http")
if errHTTPS != nil && errHTTP != nil {
return nil, fmt.Errorf("dns lookup errors: %s and %s", errHTTPS, errHTTP)
}
endpoints := make([]string, len(urls))
for i := range urls {
endpoints[i] = urls[i].String()
}
return endpoints, nil
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package client
// IsKeyNotFound returns true if the error code is ErrorCodeKeyNotFound.
func IsKeyNotFound(err error) bool {
if cErr, ok := err.(Error); ok {
return cErr.Code == ErrorCodeKeyNotFound
}
return false
}
# etcd/clientv3
[![Godoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](https://godoc.org/github.com/coreos/etcd/clientv3)
`etcd/clientv3` is the official Go etcd client for v3.
## Install
```bash
go get github.com/coreos/etcd/clientv3
```
## Get started
Create client using `clientv3.New`:
```go
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{"localhost:2379", "localhost:22379", "localhost:32379"},
DialTimeout: 5 * time.Second,
})
if err != nil {
// handle error!
}
defer cli.Close()
```
etcd v3 uses [`gRPC`](http://www.grpc.io) for remote procedure calls. And `clientv3` uses
[`grpc-go`](https://github.com/grpc/grpc-go) to connect to etcd. Make sure to close the client after using it.
If the client is not closed, the connection will have leaky goroutines. To specify client request timeout,
pass `context.WithTimeout` to APIs:
```go
ctx, cancel := context.WithTimeout(context.Background(), timeout)
resp, err := kvc.Put(ctx, "sample_key", "sample_value")
cancel()
if err != nil {
// handle error!
}
// use the response
```
etcd uses go's `vendor` directory to manage external dependencies. If `clientv3` is imported
outside of etcd, simply copy `clientv3` to the `vendor` directory or use tools like godep to
manage your own dependency, as in [vendor directories](https://golang.org/cmd/go/#hdr-Vendor_Directories).
For more detail, please read [Go vendor design](https://golang.org/s/go15vendor).
## Error Handling
etcd client returns 2 types of errors:
1. context error: canceled or deadline exceeded.
2. gRPC error: see [v3rpc/error](https://github.com/coreos/etcd/blob/master/etcdserver/api/v3rpc/error.go).
Here is the example code to handle client errors:
```go
resp, err := kvc.Put(ctx, "", "")
if err != nil {
if err == context.Canceled {
// ctx is canceled by another routine
} else if err == context.DeadlineExceeded {
// ctx is attached with a deadline and it exceeded
} else if verr, ok := err.(*v3rpc.ErrEmptyKey); ok {
// process (verr.Errors)
} else {
// bad cluster endpoints, which are not etcd servers
}
}
```
## Examples
More code examples can be found at [GoDoc](https://godoc.org/github.com/coreos/etcd/clientv3).
// Copyright 2016 Nippon Telegraph and Telephone Corporation.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"golang.org/x/net/context"
"google.golang.org/grpc"
)
type (
AuthEnableResponse pb.AuthEnableResponse
AuthUserAddResponse pb.AuthUserAddResponse
AuthUserDeleteResponse pb.AuthUserDeleteResponse
AuthUserChangePasswordResponse pb.AuthUserChangePasswordResponse
AuthRoleAddResponse pb.AuthRoleAddResponse
)
type Auth interface {
// AuthEnable enables auth of an etcd cluster.
AuthEnable(ctx context.Context) (*AuthEnableResponse, error)
// UserAdd adds a new user to an etcd cluster.
UserAdd(ctx context.Context, name string, password string) (*AuthUserAddResponse, error)
// UserDelete deletes a user from an etcd cluster.
UserDelete(ctx context.Context, name string) (*AuthUserDeleteResponse, error)
// UserChangePassword changes a password of a user.
UserChangePassword(ctx context.Context, name string, password string) (*AuthUserChangePasswordResponse, error)
// RoleAdd adds a new user to an etcd cluster.
RoleAdd(ctx context.Context, name string) (*AuthRoleAddResponse, error)
}
type auth struct {
c *Client
conn *grpc.ClientConn // conn in-use
remote pb.AuthClient
}
func NewAuth(c *Client) Auth {
conn := c.ActiveConnection()
return &auth{
conn: c.ActiveConnection(),
remote: pb.NewAuthClient(conn),
c: c,
}
}
func (auth *auth) AuthEnable(ctx context.Context) (*AuthEnableResponse, error) {
resp, err := auth.remote.AuthEnable(ctx, &pb.AuthEnableRequest{})
return (*AuthEnableResponse)(resp), err
}
func (auth *auth) UserAdd(ctx context.Context, name string, password string) (*AuthUserAddResponse, error) {
resp, err := auth.remote.UserAdd(ctx, &pb.AuthUserAddRequest{Name: name, Password: password})
return (*AuthUserAddResponse)(resp), err
}
func (auth *auth) UserDelete(ctx context.Context, name string) (*AuthUserDeleteResponse, error) {
resp, err := auth.remote.UserDelete(ctx, &pb.AuthUserDeleteRequest{Name: name})
return (*AuthUserDeleteResponse)(resp), err
}
func (auth *auth) UserChangePassword(ctx context.Context, name string, password string) (*AuthUserChangePasswordResponse, error) {
resp, err := auth.remote.UserChangePassword(ctx, &pb.AuthUserChangePasswordRequest{Name: name, Password: password})
return (*AuthUserChangePasswordResponse)(resp), err
}
func (auth *auth) RoleAdd(ctx context.Context, name string) (*AuthRoleAddResponse, error) {
resp, err := auth.remote.RoleAdd(ctx, &pb.AuthRoleAddRequest{Name: name})
return (*AuthRoleAddResponse)(resp), err
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
"errors"
"io/ioutil"
"log"
"net"
"net/url"
"strings"
"sync"
"time"
"golang.org/x/net/context"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
)
var (
ErrNoAvailableEndpoints = errors.New("etcdclient: no available endpoints")
)
// Client provides and manages an etcd v3 client session.
type Client struct {
Cluster
KV
Lease
Watcher
Auth
Maintenance
conn *grpc.ClientConn
cfg Config
creds *credentials.TransportAuthenticator
mu sync.RWMutex // protects connection selection and error list
errors []error // errors passed to retryConnection
ctx context.Context
cancel context.CancelFunc
}
// New creates a new etcdv3 client from a given configuration.
func New(cfg Config) (*Client, error) {
if cfg.RetryDialer == nil {
cfg.RetryDialer = dialEndpointList
}
if len(cfg.Endpoints) == 0 {
return nil, ErrNoAvailableEndpoints
}
return newClient(&cfg)
}
// NewFromURL creates a new etcdv3 client from a URL.
func NewFromURL(url string) (*Client, error) {
return New(Config{Endpoints: []string{url}})
}
// NewFromConfigFile creates a new etcdv3 client from a configuration file.
func NewFromConfigFile(path string) (*Client, error) {
cfg, err := configFromFile(path)
if err != nil {
return nil, err
}
return New(*cfg)
}
// Close shuts down the client's etcd connections.
func (c *Client) Close() error {
c.mu.Lock()
if c.cancel == nil {
c.mu.Unlock()
return nil
}
c.cancel()
c.cancel = nil
c.mu.Unlock()
c.Watcher.Close()
c.Lease.Close()
return c.conn.Close()
}
// Ctx is a context for "out of band" messages (e.g., for sending
// "clean up" message when another context is canceled). It is
// canceled on client Close().
func (c *Client) Ctx() context.Context { return c.ctx }
// Endpoints lists the registered endpoints for the client.
func (c *Client) Endpoints() []string { return c.cfg.Endpoints }
// Errors returns all errors that have been observed since called last.
func (c *Client) Errors() (errs []error) {
c.mu.Lock()
defer c.mu.Unlock()
errs = c.errors
c.errors = nil
return errs
}
// Dial establishes a connection for a given endpoint using the client's config
func (c *Client) Dial(endpoint string) (*grpc.ClientConn, error) {
opts := []grpc.DialOption{
grpc.WithBlock(),
grpc.WithTimeout(c.cfg.DialTimeout),
}
if c.creds != nil {
opts = append(opts, grpc.WithTransportCredentials(*c.creds))
} else {
opts = append(opts, grpc.WithInsecure())
}
proto := "tcp"
if url, uerr := url.Parse(endpoint); uerr == nil && url.Scheme == "unix" {
proto = "unix"
// strip unix:// prefix so certs work
endpoint = url.Host
}
f := func(a string, t time.Duration) (net.Conn, error) {
select {
case <-c.ctx.Done():
return nil, c.ctx.Err()
default:
}
return net.DialTimeout(proto, a, t)
}
opts = append(opts, grpc.WithDialer(f))
conn, err := grpc.Dial(endpoint, opts...)
if err != nil {
return nil, err
}
return conn, nil
}
func newClient(cfg *Config) (*Client, error) {
if cfg == nil {
cfg = &Config{RetryDialer: dialEndpointList}
}
var creds *credentials.TransportAuthenticator
if cfg.TLS != nil {
c := credentials.NewTLS(cfg.TLS)
creds = &c
}
// use a temporary skeleton client to bootstrap first connection
ctx, cancel := context.WithCancel(context.TODO())
conn, err := cfg.RetryDialer(&Client{cfg: *cfg, creds: creds, ctx: ctx})
if err != nil {
return nil, err
}
client := &Client{
conn: conn,
cfg: *cfg,
creds: creds,
ctx: ctx,
cancel: cancel,
}
client.Cluster = NewCluster(client)
client.KV = NewKV(client)
client.Lease = NewLease(client)
client.Watcher = NewWatcher(client)
client.Auth = NewAuth(client)
client.Maintenance = NewMaintenance(client)
if cfg.Logger != nil {
logger.Set(cfg.Logger)
} else {
// disable client side grpc by default
logger.Set(log.New(ioutil.Discard, "", 0))
}
return client, nil
}
// ActiveConnection returns the current in-use connection
func (c *Client) ActiveConnection() *grpc.ClientConn {
c.mu.RLock()
defer c.mu.RUnlock()
return c.conn
}
// retryConnection establishes a new connection
func (c *Client) retryConnection(oldConn *grpc.ClientConn, err error) (*grpc.ClientConn, error) {
c.mu.Lock()
defer c.mu.Unlock()
if err != nil {
c.errors = append(c.errors, err)
}
if c.cancel == nil {
return nil, c.ctx.Err()
}
if oldConn != c.conn {
// conn has already been updated
return c.conn, nil
}
oldConn.Close()
if st, _ := oldConn.State(); st != grpc.Shutdown {
// wait for shutdown so grpc doesn't leak sleeping goroutines
oldConn.WaitForStateChange(c.ctx, st)
}
conn, dialErr := c.cfg.RetryDialer(c)
if dialErr != nil {
c.errors = append(c.errors, dialErr)
return nil, dialErr
}
c.conn = conn
return c.conn, nil
}
// dialEndpointList attempts to connect to each endpoint in order until a
// connection is established.
func dialEndpointList(c *Client) (*grpc.ClientConn, error) {
var err error
for _, ep := range c.Endpoints() {
conn, curErr := c.Dial(ep)
if curErr != nil {
err = curErr
} else {
return conn, nil
}
}
return nil, err
}
// isHalted returns true if the given error and context indicate no forward
// progress can be made, even after reconnecting.
func isHalted(ctx context.Context, err error) bool {
isRPCError := strings.HasPrefix(grpc.ErrorDesc(err), "etcdserver: ")
return isRPCError || ctx.Err() != nil
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
"sync"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"golang.org/x/net/context"
"google.golang.org/grpc"
)
type (
Member pb.Member
MemberListResponse pb.MemberListResponse
MemberAddResponse pb.MemberAddResponse
MemberRemoveResponse pb.MemberRemoveResponse
MemberUpdateResponse pb.MemberUpdateResponse
)
type Cluster interface {
// MemberList lists the current cluster membership.
MemberList(ctx context.Context) (*MemberListResponse, error)
// MemberLeader returns the current leader member.
MemberLeader(ctx context.Context) (*Member, error)
// MemberAdd adds a new member into the cluster.
MemberAdd(ctx context.Context, peerAddrs []string) (*MemberAddResponse, error)
// MemberRemove removes an existing member from the cluster.
MemberRemove(ctx context.Context, id uint64) (*MemberRemoveResponse, error)
// MemberUpdate updates the peer addresses of the member.
MemberUpdate(ctx context.Context, id uint64, peerAddrs []string) (*MemberUpdateResponse, error)
}
type cluster struct {
c *Client
mu sync.Mutex
conn *grpc.ClientConn // conn in-use
remote pb.ClusterClient
}
func NewCluster(c *Client) Cluster {
conn := c.ActiveConnection()
return &cluster{
c: c,
conn: conn,
remote: pb.NewClusterClient(conn),
}
}
func (c *cluster) MemberAdd(ctx context.Context, peerAddrs []string) (*MemberAddResponse, error) {
r := &pb.MemberAddRequest{PeerURLs: peerAddrs}
resp, err := c.getRemote().MemberAdd(ctx, r)
if err == nil {
return (*MemberAddResponse)(resp), nil
}
if isHalted(ctx, err) {
return nil, err
}
go c.switchRemote(err)
return nil, err
}
func (c *cluster) MemberRemove(ctx context.Context, id uint64) (*MemberRemoveResponse, error) {
r := &pb.MemberRemoveRequest{ID: id}
resp, err := c.getRemote().MemberRemove(ctx, r)
if err == nil {
return (*MemberRemoveResponse)(resp), nil
}
if isHalted(ctx, err) {
return nil, err
}
go c.switchRemote(err)
return nil, err
}
func (c *cluster) MemberUpdate(ctx context.Context, id uint64, peerAddrs []string) (*MemberUpdateResponse, error) {
// it is safe to retry on update.
for {
r := &pb.MemberUpdateRequest{ID: id, PeerURLs: peerAddrs}
resp, err := c.getRemote().MemberUpdate(ctx, r)
if err == nil {
return (*MemberUpdateResponse)(resp), nil
}
if isHalted(ctx, err) {
return nil, err
}
err = c.switchRemote(err)
if err != nil {
return nil, err
}
}
}
func (c *cluster) MemberList(ctx context.Context) (*MemberListResponse, error) {
// it is safe to retry on list.
for {
resp, err := c.getRemote().MemberList(ctx, &pb.MemberListRequest{})
if err == nil {
return (*MemberListResponse)(resp), nil
}
if isHalted(ctx, err) {
return nil, err
}
err = c.switchRemote(err)
if err != nil {
return nil, err
}
}
}
func (c *cluster) MemberLeader(ctx context.Context) (*Member, error) {
resp, err := c.MemberList(ctx)
if err != nil {
return nil, err
}
for _, m := range resp.Members {
if m.IsLeader {
return (*Member)(m), nil
}
}
return nil, nil
}
func (c *cluster) getRemote() pb.ClusterClient {
c.mu.Lock()
defer c.mu.Unlock()
return c.remote
}
func (c *cluster) switchRemote(prevErr error) error {
newConn, err := c.c.retryConnection(c.conn, prevErr)
if err != nil {
return err
}
c.mu.Lock()
defer c.mu.Unlock()
c.conn = newConn
c.remote = pb.NewClusterClient(c.conn)
return nil
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
)
type CompareTarget int
type CompareResult int
const (
CompareVersion CompareTarget = iota
CompareCreated
CompareModified
CompareValue
)
type Cmp pb.Compare
func Compare(cmp Cmp, result string, v interface{}) Cmp {
var r pb.Compare_CompareResult
switch result {
case "=":
r = pb.Compare_EQUAL
case ">":
r = pb.Compare_GREATER
case "<":
r = pb.Compare_LESS
default:
panic("Unknown result op")
}
cmp.Result = r
switch cmp.Target {
case pb.Compare_VALUE:
val, ok := v.(string)
if !ok {
panic("bad compare value")
}
cmp.TargetUnion = &pb.Compare_Value{Value: []byte(val)}
case pb.Compare_VERSION:
cmp.TargetUnion = &pb.Compare_Version{Version: mustInt64(v)}
case pb.Compare_CREATE:
cmp.TargetUnion = &pb.Compare_CreateRevision{CreateRevision: mustInt64(v)}
case pb.Compare_MOD:
cmp.TargetUnion = &pb.Compare_ModRevision{ModRevision: mustInt64(v)}
default:
panic("Unknown compare type")
}
return cmp
}
func Value(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_VALUE}
}
func Version(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_VERSION}
}
func CreateRevision(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_CREATE}
}
func ModRevision(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_MOD}
}
func mustInt64(val interface{}) int64 {
if v, ok := val.(int64); ok {
return v
}
if v, ok := val.(int); ok {
return int64(v)
}
panic("bad value")
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package concurrency implements concurrency operations on top of
// etcd such as distributed locks, barriers, and elections.
package concurrency
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package concurrency
import (
"errors"
v3 "github.com/coreos/etcd/clientv3"
"github.com/coreos/etcd/storage/storagepb"
"golang.org/x/net/context"
)
var (
ErrElectionNotLeader = errors.New("election: not leader")
ErrElectionNoLeader = errors.New("election: no leader")
)
type Election struct {
client *v3.Client
keyPrefix string
leaderKey string
leaderRev int64
leaderSession *Session
}
// NewElection returns a new election on a given key prefix.
func NewElection(client *v3.Client, pfx string) *Election {
return &Election{client: client, keyPrefix: pfx}
}
// Campaign puts a value as eligible for the election. It blocks until
// it is elected, an error occurs, or the context is cancelled.
func (e *Election) Campaign(ctx context.Context, val string) error {
s, serr := NewSession(e.client)
if serr != nil {
return serr
}
k, rev, err := NewUniqueKV(ctx, e.client, e.keyPrefix, val, v3.WithLease(s.Lease()))
if err == nil {
err = waitDeletes(ctx, e.client, e.keyPrefix, v3.WithPrefix(), v3.WithRev(rev-1))
}
if err != nil {
// clean up in case of context cancel
select {
case <-ctx.Done():
e.client.Delete(e.client.Ctx(), k)
default:
}
return err
}
e.leaderKey, e.leaderRev, e.leaderSession = k, rev, s
return nil
}
// Proclaim lets the leader announce a new value without another election.
func (e *Election) Proclaim(ctx context.Context, val string) error {
if e.leaderSession == nil {
return ErrElectionNotLeader
}
cmp := v3.Compare(v3.CreateRevision(e.leaderKey), "=", e.leaderRev)
txn := e.client.Txn(ctx).If(cmp)
txn = txn.Then(v3.OpPut(e.leaderKey, val, v3.WithLease(e.leaderSession.Lease())))
tresp, terr := txn.Commit()
if terr != nil {
return terr
}
if !tresp.Succeeded {
e.leaderKey = ""
return ErrElectionNotLeader
}
return nil
}
// Resign lets a leader start a new election.
func (e *Election) Resign() (err error) {
if e.leaderSession == nil {
return nil
}
_, err = e.client.Delete(e.client.Ctx(), e.leaderKey)
e.leaderKey = ""
e.leaderSession = nil
return err
}
// Leader returns the leader value for the current election.
func (e *Election) Leader() (string, error) {
resp, err := e.client.Get(e.client.Ctx(), e.keyPrefix, v3.WithFirstCreate()...)
if err != nil {
return "", err
} else if len(resp.Kvs) == 0 {
// no leader currently elected
return "", ErrElectionNoLeader
}
return string(resp.Kvs[0].Value), nil
}
// Observe returns a channel that observes all leader proposal values as
// GetResponse values on the current leader key. The channel closes when
// the context is cancelled or the underlying watcher is otherwise disrupted.
func (e *Election) Observe(ctx context.Context) <-chan v3.GetResponse {
retc := make(chan v3.GetResponse)
go e.observe(ctx, retc)
return retc
}
func (e *Election) observe(ctx context.Context, ch chan<- v3.GetResponse) {
defer close(ch)
for {
resp, err := e.client.Get(ctx, e.keyPrefix, v3.WithFirstCreate()...)
if err != nil {
return
}
var kv *storagepb.KeyValue
cctx, cancel := context.WithCancel(ctx)
if len(resp.Kvs) == 0 {
// wait for first key put on prefix
opts := []v3.OpOption{v3.WithRev(resp.Header.Revision), v3.WithPrefix()}
wch := e.client.Watch(cctx, e.keyPrefix, opts...)
for kv == nil {
wr, ok := <-wch
if !ok || wr.Err() != nil {
cancel()
return
}
// only accept PUTs; a DELETE will make observe() spin
for _, ev := range wr.Events {
if ev.Type == storagepb.PUT {
kv = ev.Kv
break
}
}
}
} else {
kv = resp.Kvs[0]
}
wch := e.client.Watch(cctx, string(kv.Key), v3.WithRev(kv.ModRevision))
keyDeleted := false
for !keyDeleted {
wr, ok := <-wch
if !ok {
return
}
for _, ev := range wr.Events {
if ev.Type == storagepb.DELETE {
keyDeleted = true
break
}
resp.Header = &wr.Header
resp.Kvs = []*storagepb.KeyValue{ev.Kv}
select {
case ch <- *resp:
case <-cctx.Done():
return
}
}
}
cancel()
}
}
// Key returns the leader key if elected, empty string otherwise.
func (e *Election) Key() string { return e.leaderKey }
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package concurrency
import (
"fmt"
"math"
"time"
v3 "github.com/coreos/etcd/clientv3"
"github.com/coreos/etcd/storage/storagepb"
"golang.org/x/net/context"
)
// NewUniqueKey creates a new key from a given prefix.
func NewUniqueKey(ctx context.Context, kv v3.KV, pfx string, opts ...v3.OpOption) (string, int64, error) {
return NewUniqueKV(ctx, kv, pfx, "", opts...)
}
func NewUniqueKV(ctx context.Context, kv v3.KV, pfx, val string, opts ...v3.OpOption) (string, int64, error) {
for {
newKey := fmt.Sprintf("%s/%v", pfx, time.Now().UnixNano())
put := v3.OpPut(newKey, val, opts...)
cmp := v3.Compare(v3.ModRevision(newKey), "=", 0)
resp, err := kv.Txn(ctx).If(cmp).Then(put).Commit()
if err != nil {
return "", 0, err
}
if !resp.Succeeded {
continue
}
return newKey, resp.Header.Revision, nil
}
}
func waitUpdate(ctx context.Context, client *v3.Client, key string, opts ...v3.OpOption) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wresp, ok := <-client.Watch(cctx, key, opts...)
if !ok {
return ctx.Err()
}
return wresp.Err()
}
func waitDelete(ctx context.Context, client *v3.Client, key string, rev int64) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wch := client.Watch(cctx, key, v3.WithRev(rev))
for wr := range wch {
for _, ev := range wr.Events {
if ev.Type == storagepb.DELETE {
return nil
}
}
}
if err := ctx.Err(); err != nil {
return err
}
return fmt.Errorf("lost watcher waiting for delete")
}
// waitDeletes efficiently waits until all keys matched by Get(key, opts...) are deleted
func waitDeletes(ctx context.Context, client *v3.Client, key string, opts ...v3.OpOption) error {
getOpts := []v3.OpOption{v3.WithSort(v3.SortByCreateRevision, v3.SortAscend)}
getOpts = append(getOpts, opts...)
resp, err := client.Get(ctx, key, getOpts...)
maxRev := int64(math.MaxInt64)
getOpts = append(getOpts, v3.WithRev(0))
for err == nil {
for len(resp.Kvs) > 0 {
i := len(resp.Kvs) - 1
if resp.Kvs[i].CreateRevision <= maxRev {
break
}
resp.Kvs = resp.Kvs[:i]
}
if len(resp.Kvs) == 0 {
break
}
lastKV := resp.Kvs[len(resp.Kvs)-1]
maxRev = lastKV.CreateRevision
err = waitDelete(ctx, client, string(lastKV.Key), maxRev)
if err != nil || len(resp.Kvs) == 1 {
break
}
getOpts = append(getOpts, v3.WithLimit(int64(len(resp.Kvs)-1)))
resp, err = client.Get(ctx, key, getOpts...)
}
return err
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package concurrency
import (
"sync"
v3 "github.com/coreos/etcd/clientv3"
"golang.org/x/net/context"
)
// Mutex implements the sync Locker interface with etcd
type Mutex struct {
client *v3.Client
pfx string
myKey string
myRev int64
}
func NewMutex(client *v3.Client, pfx string) *Mutex {
return &Mutex{client, pfx, "", -1}
}
// Lock locks the mutex with a cancellable context. If the context is cancelled
// while trying to acquire the lock, the mutex tries to clean its stale lock entry.
func (m *Mutex) Lock(ctx context.Context) error {
s, err := NewSession(m.client)
if err != nil {
return err
}
// put self in lock waiters via myKey; oldest waiter holds lock
m.myKey, m.myRev, err = NewUniqueKey(ctx, m.client, m.pfx, v3.WithLease(s.Lease()))
// wait for deletion revisions prior to myKey
err = waitDeletes(ctx, m.client, m.pfx, v3.WithPrefix(), v3.WithRev(m.myRev-1))
// release lock key if cancelled
select {
case <-ctx.Done():
m.Unlock()
default:
}
return err
}
func (m *Mutex) Unlock() error {
if _, err := m.client.Delete(m.client.Ctx(), m.myKey); err != nil {
return err
}
m.myKey = "\x00"
m.myRev = -1
return nil
}
func (m *Mutex) IsOwner() v3.Cmp {
return v3.Compare(v3.CreateRevision(m.myKey), "=", m.myRev)
}
func (m *Mutex) Key() string { return m.myKey }
type lockerMutex struct{ *Mutex }
func (lm *lockerMutex) Lock() {
if err := lm.Mutex.Lock(lm.client.Ctx()); err != nil {
panic(err)
}
}
func (lm *lockerMutex) Unlock() {
if err := lm.Mutex.Unlock(); err != nil {
panic(err)
}
}
// NewLocker creates a sync.Locker backed by an etcd mutex.
func NewLocker(client *v3.Client, pfx string) sync.Locker {
return &lockerMutex{NewMutex(client, pfx)}
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package concurrency
import (
"sync"
v3 "github.com/coreos/etcd/clientv3"
"golang.org/x/net/context"
)
// only keep one ephemeral lease per client
var clientSessions clientSessionMgr = clientSessionMgr{sessions: make(map[*v3.Client]*Session)}
const sessionTTL = 60
type clientSessionMgr struct {
sessions map[*v3.Client]*Session
mu sync.Mutex
}
// Session represents a lease kept alive for the lifetime of a client.
// Fault-tolerant applications may use sessions to reason about liveness.
type Session struct {
client *v3.Client
id v3.LeaseID
cancel context.CancelFunc
donec <-chan struct{}
}
// NewSession gets the leased session for a client.
func NewSession(client *v3.Client) (*Session, error) {
clientSessions.mu.Lock()
defer clientSessions.mu.Unlock()
if s, ok := clientSessions.sessions[client]; ok {
return s, nil
}
resp, err := client.Grant(client.Ctx(), sessionTTL)
if err != nil {
return nil, err
}
id := v3.LeaseID(resp.ID)
ctx, cancel := context.WithCancel(client.Ctx())
keepAlive, err := client.KeepAlive(ctx, id)
if err != nil || keepAlive == nil {
return nil, err
}
donec := make(chan struct{})
s := &Session{client: client, id: id, cancel: cancel, donec: donec}
clientSessions.sessions[client] = s
// keep the lease alive until client error or cancelled context
go func() {
defer func() {
clientSessions.mu.Lock()
delete(clientSessions.sessions, client)
clientSessions.mu.Unlock()
close(donec)
}()
for range keepAlive {
// eat messages until keep alive channel closes
}
}()
return s, nil
}
// Lease is the lease ID for keys bound to the session.
func (s *Session) Lease() v3.LeaseID { return s.id }
// Done returns a channel that closes when the lease is orphaned, expires, or
// is otherwise no longer being refreshed.
func (s *Session) Done() <-chan struct{} { return s.donec }
// Orphan ends the refresh for the session lease. This is useful
// in case the state of the client connection is indeterminate (revoke
// would fail) or when transferring lease ownership.
func (s *Session) Orphan() {
s.cancel()
<-s.donec
}
// Close orphans the session and revokes the session lease.
func (s *Session) Close() error {
s.Orphan()
_, err := s.client.Revoke(s.client.Ctx(), s.id)
return err
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package concurrency
import (
v3 "github.com/coreos/etcd/clientv3"
"golang.org/x/net/context"
)
// STM is an interface for software transactional memory.
type STM interface {
// Get returns the value for a key and inserts the key in the txn's read set.
// If Get fails, it aborts the transaction with an error, never returning.
Get(key string) string
// Put adds a value for a key to the write set.
Put(key, val string, opts ...v3.OpOption)
// Rev returns the revision of a key in the read set.
Rev(key string) int64
// Del deletes a key.
Del(key string)
// commit attempts to apply the txn's changes to the server.
commit() *v3.TxnResponse
reset()
}
// stmError safely passes STM errors through panic to the STM error channel.
type stmError struct{ err error }
// NewSTMRepeatable initiates new repeatable read transaction; reads within
// the same transaction attempt always return the same data.
func NewSTMRepeatable(ctx context.Context, c *v3.Client, apply func(STM) error) (*v3.TxnResponse, error) {
s := &stm{client: c, ctx: ctx, getOpts: []v3.OpOption{v3.WithSerializable()}}
return runSTM(s, apply)
}
// NewSTMSerializable initiates a new serialized transaction; reads within the
// same transactiona attempt return data from the revision of the first read.
func NewSTMSerializable(ctx context.Context, c *v3.Client, apply func(STM) error) (*v3.TxnResponse, error) {
s := &stmSerializable{
stm: stm{client: c, ctx: ctx},
prefetch: make(map[string]*v3.GetResponse),
}
return runSTM(s, apply)
}
type stmResponse struct {
resp *v3.TxnResponse
err error
}
func runSTM(s STM, apply func(STM) error) (*v3.TxnResponse, error) {
outc := make(chan stmResponse, 1)
go func() {
defer func() {
if r := recover(); r != nil {
e, ok := r.(stmError)
if !ok {
// client apply panicked
panic(r)
}
outc <- stmResponse{nil, e.err}
}
}()
var out stmResponse
for {
s.reset()
if out.err = apply(s); out.err != nil {
break
}
if out.resp = s.commit(); out.resp != nil {
break
}
}
outc <- out
}()
r := <-outc
return r.resp, r.err
}
// stm implements repeatable-read software transactional memory over etcd
type stm struct {
client *v3.Client
ctx context.Context
// rset holds read key values and revisions
rset map[string]*v3.GetResponse
// wset holds overwritten keys and their values
wset map[string]stmPut
// getOpts are the opts used for gets
getOpts []v3.OpOption
}
type stmPut struct {
val string
op v3.Op
}
func (s *stm) Get(key string) string {
if wv, ok := s.wset[key]; ok {
return wv.val
}
return respToValue(s.fetch(key))
}
func (s *stm) Put(key, val string, opts ...v3.OpOption) {
s.wset[key] = stmPut{val, v3.OpPut(key, val, opts...)}
}
func (s *stm) Del(key string) { s.wset[key] = stmPut{"", v3.OpDelete(key)} }
func (s *stm) Rev(key string) int64 {
if resp := s.fetch(key); resp != nil && len(resp.Kvs) != 0 {
return resp.Kvs[0].ModRevision
}
return 0
}
func (s *stm) commit() *v3.TxnResponse {
txnresp, err := s.client.Txn(s.ctx).If(s.cmps()...).Then(s.puts()...).Commit()
if err != nil {
panic(stmError{err})
}
if txnresp.Succeeded {
return txnresp
}
return nil
}
// cmps guards the txn from updates to read set
func (s *stm) cmps() (cmps []v3.Cmp) {
for k, rk := range s.rset {
cmps = append(cmps, isKeyCurrent(k, rk))
}
return
}
func (s *stm) fetch(key string) *v3.GetResponse {
if resp, ok := s.rset[key]; ok {
return resp
}
resp, err := s.client.Get(s.ctx, key, s.getOpts...)
if err != nil {
panic(stmError{err})
}
s.rset[key] = resp
return resp
}
// puts is the list of ops for all pending writes
func (s *stm) puts() (puts []v3.Op) {
for _, v := range s.wset {
puts = append(puts, v.op)
}
return
}
func (s *stm) reset() {
s.rset = make(map[string]*v3.GetResponse)
s.wset = make(map[string]stmPut)
}
type stmSerializable struct {
stm
prefetch map[string]*v3.GetResponse
}
func (s *stmSerializable) Get(key string) string {
if wv, ok := s.wset[key]; ok {
return wv.val
}
firstRead := len(s.rset) == 0
if resp, ok := s.prefetch[key]; ok {
delete(s.prefetch, key)
s.rset[key] = resp
}
resp := s.stm.fetch(key)
if firstRead {
// txn's base revision is defined by the first read
s.getOpts = []v3.OpOption{
v3.WithRev(resp.Header.Revision),
v3.WithSerializable(),
}
}
return respToValue(resp)
}
func (s *stmSerializable) Rev(key string) int64 {
s.Get(key)
return s.stm.Rev(key)
}
func (s *stmSerializable) gets() (keys []string, ops []v3.Op) {
for k := range s.rset {
keys = append(keys, k)
ops = append(ops, v3.OpGet(k))
}
return
}
func (s *stmSerializable) commit() *v3.TxnResponse {
keys, getops := s.gets()
txn := s.client.Txn(s.ctx).If(s.cmps()...).Then(s.puts()...)
// use Else to prefetch keys in case of conflict to save a round trip
txnresp, err := txn.Else(getops...).Commit()
if err != nil {
panic(stmError{err})
}
if txnresp.Succeeded {
return txnresp
}
// load prefetch with Else data
for i := range keys {
resp := txnresp.Responses[i].GetResponseRange()
s.rset[keys[i]] = (*v3.GetResponse)(resp)
}
s.prefetch = s.rset
s.getOpts = nil
return nil
}
func isKeyCurrent(k string, r *v3.GetResponse) v3.Cmp {
rev := r.Header.Revision + 1
if len(r.Kvs) != 0 {
rev = r.Kvs[0].ModRevision + 1
}
return v3.Compare(v3.ModRevision(k), "<", rev)
}
func respToValue(resp *v3.GetResponse) string {
if len(resp.Kvs) == 0 {
return ""
}
return string(resp.Kvs[0].Value)
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
"crypto/tls"
"crypto/x509"
"io/ioutil"
"time"
"github.com/coreos/etcd/pkg/tlsutil"
"github.com/ghodss/yaml"
"google.golang.org/grpc"
)
// EndpointDialer is a policy for choosing which endpoint to dial next
type EndpointDialer func(*Client) (*grpc.ClientConn, error)
type Config struct {
// Endpoints is a list of URLs
Endpoints []string
// RetryDialer chooses the next endpoint to use
RetryDialer EndpointDialer
// DialTimeout is the timeout for failing to establish a connection.
DialTimeout time.Duration
// TLS holds the client secure credentials, if any.
TLS *tls.Config
// Logger is the logger used by client library.
Logger Logger
}
type YamlConfig struct {
Endpoints []string `json:"endpoints"`
DialTimeout time.Duration `json:"dial-timeout"`
InsecureTransport bool `json:"insecure-transport"`
InsecureSkipTLSVerify bool `json:"insecure-skip-tls-verify"`
Certfile string `json:"cert-file"`
Keyfile string `json:"key-file"`
CAfile string `json:"ca-file"`
}
func configFromFile(fpath string) (*Config, error) {
b, err := ioutil.ReadFile(fpath)
if err != nil {
return nil, err
}
yc := &YamlConfig{}
err = yaml.Unmarshal(b, yc)
if err != nil {
return nil, err
}
cfg := &Config{
Endpoints: yc.Endpoints,
DialTimeout: yc.DialTimeout,
}
if yc.InsecureTransport {
cfg.TLS = nil
return cfg, nil
}
var (
cert *tls.Certificate
cp *x509.CertPool
)
if yc.Certfile != "" && yc.Keyfile != "" {
cert, err = tlsutil.NewCert(yc.Certfile, yc.Keyfile, nil)
if err != nil {
return nil, err
}
}
if yc.CAfile != "" {
cp, err = tlsutil.NewCertPool([]string{yc.CAfile})
if err != nil {
return nil, err
}
}
tlscfg := &tls.Config{
MinVersion: tls.VersionTLS10,
InsecureSkipVerify: yc.InsecureSkipTLSVerify,
RootCAs: cp,
}
if cert != nil {
tlscfg.Certificates = []tls.Certificate{*cert}
}
cfg.TLS = tlscfg
return cfg, nil
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package clientv3 implements the official Go etcd client for v3.
//
// Create client using `clientv3.New`:
//
// cli, err := clientv3.New(clientv3.Config{
// Endpoints: []string{"localhost:2379", "localhost:22379", "localhost:32379"},
// DialTimeout: 5 * time.Second,
// })
// if err != nil {
// // handle error!
// }
// defer cli.Close()
//
// Make sure to close the client after using it. If the client is not closed, the
// connection will have leaky goroutines.
//
// To specify client request timeout, pass context.WithTimeout to APIs:
//
// ctx, cancel := context.WithTimeout(context.Background(), timeout)
// resp, err := kvc.Put(ctx, "sample_key", "sample_value")
// cancel()
// if err != nil {
// // handle error!
// }
// // use the response
//
// The Client has internal state (watchers and leases), so Clients should be reused instead of created as needed.
// Clients are safe for concurrent use by multiple goroutines.
//
// etcd client returns 2 types of errors:
//
// 1. context error: canceled or deadline exceeded.
// 2. gRPC error: see https://github.com/coreos/etcd/blob/master/etcdserver/api/v3rpc/error.go.
//
// Here is the example code to handle client errors:
//
// resp, err := kvc.Put(ctx, "", "")
// if err != nil {
// if err == context.Canceled {
// // ctx is canceled by another routine
// } else if err == context.DeadlineExceeded {
// // ctx is attached with a deadline and it exceeded
// } else if verr, ok := err.(*v3rpc.ErrEmptyKey); ok {
// // process (verr.Errors)
// } else {
// // bad cluster endpoints, which are not etcd servers
// }
// }
//
package clientv3
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package integration implements tests built upon embedded etcd, and focuses on
// correctness of etcd client.
package integration
// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
"sync"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"golang.org/x/net/context"
"google.golang.org/grpc"
)
type (
PutResponse pb.PutResponse
GetResponse pb.RangeResponse
DeleteResponse pb.DeleteRangeResponse
TxnResponse pb.TxnResponse
)
type KV interface {
// Put puts a key-value pair into etcd.
// Note that key,value can be plain bytes array and string is
// an immutable representation of that bytes array.
// To get a string of bytes, do string([]byte(0x10, 0x20)).
Put(ctx context.Context, key, val string, opts ...OpOption) (*PutResponse, error)
// Get retrieves keys.
// By default, Get will return the value for "key", if any.
// When passed WithRange(end), Get will return the keys in the range [key, end).
// When passed WithFromKey(), Get returns keys greater than or equal to key.
// When passed WithRev(rev) with rev > 0, Get retrieves keys at the given revision;
// if the required revision is compacted, the request will fail with ErrCompacted .
// When passed WithLimit(limit), the number of returned keys is bounded by limit.
// When passed WithSort(), the keys will be sorted.
Get(ctx context.Context, key string, opts ...OpOption) (*GetResponse, error)
// Delete deletes a key, or optionally using WithRange(end), [key, end).
Delete(ctx context.Context, key string, opts ...OpOption) (*DeleteResponse, error)
// Compact compacts etcd KV history before the given rev.
Compact(ctx context.Context, rev int64) error
// Do applies a single Op on KV without a transaction.
// Do is useful when declaring operations to be issued at a later time
// whereas Get/Put/Delete are for better suited for when the operation
// should be immediately issued at time of declaration.
// Do applies a single Op on KV without a transaction.
// Do is useful when creating arbitrary operations to be issued at a
// later time; the user can range over the operations, calling Do to
// execute them. Get/Put/Delete, on the other hand, are best suited
// for when the operation should be issued at the time of declaration.
Do(ctx context.Context, op Op) (OpResponse, error)
// Txn creates a transaction.
Txn(ctx context.Context) Txn
}
type OpResponse struct {
put *PutResponse
get *GetResponse
del *DeleteResponse
}
type kv struct {
c *Client
mu sync.Mutex // guards all fields
conn *grpc.ClientConn // conn in-use
remote pb.KVClient
}
func NewKV(c *Client) KV {
conn := c.ActiveConnection()
remote := pb.NewKVClient(conn)
return &kv{
conn: c.ActiveConnection(),
remote: remote,
c: c,
}
}
func (kv *kv) Put(ctx context.Context, key, val string, opts ...OpOption) (*PutResponse, error) {
r, err := kv.Do(ctx, OpPut(key, val, opts...))
return r.put, err
}
func (kv *kv) Get(ctx context.Context, key string, opts ...OpOption) (*GetResponse, error) {
r, err := kv.Do(ctx, OpGet(key, opts...))
return r.get, err
}
func (kv *kv) Delete(ctx context.Context, key string, opts ...OpOption) (*DeleteResponse, error) {
r, err := kv.Do(ctx, OpDelete(key, opts...))
return r.del, err
}
func (kv *kv) Compact(ctx context.Context, rev int64) error {
r := &pb.CompactionRequest{Revision: rev}
_, err := kv.getRemote().Compact(ctx, r)
if err == nil {
return nil
}
if isHalted(ctx, err) {
return err
}
go kv.switchRemote(err)
return err
}
func (kv *kv) Txn(ctx context.Context) Txn {
return &txn{
kv: kv,
ctx: ctx,
}
}
func (kv *kv) Do(ctx context.Context, op Op) (OpResponse, error) {
for {
var err error
switch op.t {
// TODO: handle other ops
case tRange:
var resp *pb.RangeResponse
r := &pb.RangeRequest{Key: op.key, RangeEnd: op.end, Limit: op.limit, Revision: op.rev, Serializable: op.serializable}
if op.sort != nil {
r.SortOrder = pb.RangeRequest_SortOrder(op.sort.Order)
r.SortTarget = pb.RangeRequest_SortTarget(op.sort.Target)
}
resp, err = kv.getRemote().Range(ctx, r)
if err == nil {
return OpResponse{get: (*GetResponse)(resp)}, nil
}
case tPut:
var resp *pb.PutResponse
r := &pb.PutRequest{Key: op.key, Value: op.val, Lease: int64(op.leaseID)}
resp, err = kv.getRemote().Put(ctx, r)
if err == nil {
return OpResponse{put: (*PutResponse)(resp)}, nil
}
case tDeleteRange:
var resp *pb.DeleteRangeResponse
r := &pb.DeleteRangeRequest{Key: op.key, RangeEnd: op.end}
resp, err = kv.getRemote().DeleteRange(ctx, r)
if err == nil {
return OpResponse{del: (*DeleteResponse)(resp)}, nil
}
default:
panic("Unknown op")
}
if isHalted(ctx, err) {
return OpResponse{}, err
}
// do not retry on modifications
if op.isWrite() {
go kv.switchRemote(err)
return OpResponse{}, err
}
if nerr := kv.switchRemote(err); nerr != nil {
return OpResponse{}, nerr
}
}
}
func (kv *kv) switchRemote(prevErr error) error {
// Usually it's a bad idea to lock on network i/o but here it's OK
// since the link is down and new requests can't be processed anyway.
// Likewise, if connecting stalls, closing the Client can break the
// lock via context cancelation.
kv.mu.Lock()
defer kv.mu.Unlock()
newConn, err := kv.c.retryConnection(kv.conn, prevErr)
if err != nil {
return err
}
kv.conn = newConn
kv.remote = pb.NewKVClient(kv.conn)
return nil
}
func (kv *kv) getRemote() pb.KVClient {
kv.mu.Lock()
defer kv.mu.Unlock()
return kv.remote
}
// Copyright 2016 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package clientv3
import (
"sync"
"time"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"golang.org/x/net/context"
"google.golang.org/grpc"
)
type (
LeaseGrantResponse pb.LeaseGrantResponse
LeaseRevokeResponse pb.LeaseRevokeResponse
LeaseKeepAliveResponse pb.LeaseKeepAliveResponse
LeaseID int64
)
const (
// a small buffer to store unsent lease responses.
leaseResponseChSize = 16
// NoLease is a lease ID for the absence of a lease.
NoLease LeaseID = 0
)
type Lease interface {
// Grant creates a new lease.
Grant(ctx context.Context, ttl int64) (*LeaseGrantResponse, error)
// Revoke revokes the given lease.
Revoke(ctx context.Context, id LeaseID) (*LeaseRevokeResponse, error)
// KeepAlive keeps the given lease alive forever.
KeepAlive(ctx context.Context, id LeaseID) (<-chan *LeaseKeepAliveResponse, error)
// KeepAliveOnce renews the lease once. In most of the cases, Keepalive
// should be used instead of KeepAliveOnce.
KeepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error)
// Close releases all resources Lease keeps for efficient communication
// with the etcd server.
Close() error
}
type lessor struct {
c *Client
mu sync.Mutex // guards all fields
conn *grpc.ClientConn // conn in-use
// donec is closed when recvKeepAliveLoop stops
donec chan struct{}
remote pb.LeaseClient
stream pb.Lease_LeaseKeepAliveClient
streamCancel context.CancelFunc
stopCtx context.Context
stopCancel context.CancelFunc
keepAlives map[LeaseID]*keepAlive
}
// keepAlive multiplexes a keepalive for a lease over multiple channels
type keepAlive struct {
chs []chan<- *LeaseKeepAliveResponse
ctxs []context.Context
// deadline is the next time to send a keep alive message
deadline time.Time
// donec is closed on lease revoke, expiration, or cancel.
donec chan struct{}
}
func NewLease(c *Client) Lease {
l := &lessor{
c: c,
conn: c.ActiveConnection(),
donec: make(chan struct{}),
keepAlives: make(map[LeaseID]*keepAlive),
}
l.remote = pb.NewLeaseClient(l.conn)
l.stopCtx, l.stopCancel = context.WithCancel(context.Background())
go l.recvKeepAliveLoop()
return l
}
func (l *lessor) Grant(ctx context.Context, ttl int64) (*LeaseGrantResponse, error) {
cctx, cancel := context.WithCancel(ctx)
done := cancelWhenStop(cancel, l.stopCtx.Done())
defer close(done)
for {
r := &pb.LeaseGrantRequest{TTL: ttl}
resp, err := l.getRemote().LeaseGrant(cctx, r)
if err == nil {
return (*LeaseGrantResponse)(resp), nil
}
if isHalted(cctx, err) {
return nil, err
}
if nerr := l.switchRemoteAndStream(err); nerr != nil {
return nil, nerr
}
}
}
func (l *lessor) Revoke(ctx context.Context, id LeaseID) (*LeaseRevokeResponse, error) {
cctx, cancel := context.WithCancel(ctx)
done := cancelWhenStop(cancel, l.stopCtx.Done())
defer close(done)
for {
r := &pb.LeaseRevokeRequest{ID: int64(id)}
resp, err := l.getRemote().LeaseRevoke(cctx, r)
if err == nil {
return (*LeaseRevokeResponse)(resp), nil
}
if isHalted(ctx, err) {
return nil, err
}
if nerr := l.switchRemoteAndStream(err); nerr != nil {
return nil, nerr
}
}
}
func (l *lessor) KeepAlive(ctx context.Context, id LeaseID) (<-chan *LeaseKeepAliveResponse, error) {
ch := make(chan *LeaseKeepAliveResponse, leaseResponseChSize)
l.mu.Lock()
ka, ok := l.keepAlives[id]
if !ok {
// create fresh keep alive
ka = &keepAlive{
chs: []chan<- *LeaseKeepAliveResponse{ch},
ctxs: []context.Context{ctx},
deadline: time.Now(),
donec: make(chan struct{}),
}
l.keepAlives[id] = ka
} else {
// add channel and context to existing keep alive
ka.ctxs = append(ka.ctxs, ctx)
ka.chs = append(ka.chs, ch)
}
l.mu.Unlock()
go l.keepAliveCtxCloser(id, ctx, ka.donec)
return ch, nil
}
func (l *lessor) KeepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error) {
cctx, cancel := context.WithCancel(ctx)
done := cancelWhenStop(cancel, l.stopCtx.Done())
defer close(done)
for {
resp, err := l.keepAliveOnce(cctx, id)
if err == nil {
return resp, err
}
nerr := l.switchRemoteAndStream(err)
if nerr != nil {
return nil, nerr
}
}
}
func (l *lessor) Close() error {
l.stopCancel()
<-l.donec
return nil
}
func (l *lessor) keepAliveCtxCloser(id LeaseID, ctx context.Context, donec <-chan struct{}) {
select {
case <-donec:
return
case <-l.donec:
return
case <-ctx.Done():
}
l.mu.Lock()
defer l.mu.Unlock()
ka, ok := l.keepAlives[id]
if !ok {
return
}
// close channel and remove context if still associated with keep alive
for i, c := range ka.ctxs {
if c == ctx {
close(ka.chs[i])
ka.ctxs = append(ka.ctxs[:i], ka.ctxs[i+1:]...)
ka.chs = append(ka.chs[:i], ka.chs[i+1:]...)
break
}
}
// remove if no one more listeners
if len(ka.chs) == 0 {
delete(l.keepAlives, id)
}
}
func (l *lessor) keepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error) {
stream, err := l.getRemote().LeaseKeepAlive(ctx)
if err != nil {
return nil, err
}
err = stream.Send(&pb.LeaseKeepAliveRequest{ID: int64(id)})
if err != nil {
return nil, err
}
resp, rerr := stream.Recv()
if rerr != nil {
return nil, rerr
}
return (*LeaseKeepAliveResponse)(resp), nil
}
func (l *lessor) recvKeepAliveLoop() {
defer func() {
l.stopCancel()
l.mu.Lock()
close(l.donec)
for _, ka := range l.keepAlives {
ka.Close()
}
l.keepAlives = make(map[LeaseID]*keepAlive)
l.mu.Unlock()
}()
stream, serr := l.resetRecv()
for serr == nil {
resp, err := stream.Recv()
if err != nil {
if isHalted(l.stopCtx, err) {
return
}
stream, serr = l.resetRecv()
continue
}
l.recvKeepAlive(resp)
}
}
// resetRecv opens a new lease stream and starts sending LeaseKeepAliveRequests
func (l *lessor) resetRecv() (pb.Lease_LeaseKeepAliveClient, error) {
if err := l.switchRemoteAndStream(nil); err != nil {
return nil, err
}
stream := l.getKeepAliveStream()
go l.sendKeepAliveLoop(stream)
return stream, nil
}
// recvKeepAlive updates a lease based on its LeaseKeepAliveResponse
func (l *lessor) recvKeepAlive(resp *pb.LeaseKeepAliveResponse) {
id := LeaseID(resp.ID)
l.mu.Lock()
defer l.mu.Unlock()
ka, ok := l.keepAlives[id]
if !ok {
return
}
if resp.TTL <= 0 {
// lease expired; close all keep alive channels
delete(l.keepAlives, id)
ka.Close()
return
}
// send update to all channels
nextDeadline := time.Now().Add(1 + time.Duration(resp.TTL/3)*time.Second)
for _, ch := range ka.chs {
select {
case ch <- (*LeaseKeepAliveResponse)(resp):
ka.deadline = nextDeadline
default:
}
}
}
// sendKeepAliveLoop sends LeaseKeepAliveRequests for the lifetime of a lease stream
func (l *lessor) sendKeepAliveLoop(stream pb.Lease_LeaseKeepAliveClient) {
for {
select {
case <-time.After(500 * time.Millisecond):
case <-l.donec:
return
case <-l.stopCtx.Done():
return
}
tosend := make([]LeaseID, 0)
now := time.Now()
l.mu.Lock()
for id, ka := range l.keepAlives {
if ka.deadline.Before(now) {
tosend = append(tosend, id)
}
}
l.mu.Unlock()
for _, id := range tosend {
r := &pb.LeaseKeepAliveRequest{ID: int64(id)}
if err := stream.Send(r); err != nil {
// TODO do something with this error?
return
}
}
}
}
func (l *lessor) getRemote() pb.LeaseClient {
l.mu.Lock()
defer l.mu.Unlock()
return l.remote
}
func (l *lessor) getKeepAliveStream() pb.Lease_LeaseKeepAliveClient {
l.mu.Lock()
defer l.mu.Unlock()
return l.stream
}
func (l *lessor) switchRemoteAndStream(prevErr error) error {
l.mu.Lock()
conn := l.conn
l.mu.Unlock()
var (
err error
newConn *grpc.ClientConn
)
if prevErr != nil {
conn.Close()
newConn, err = l.c.retryConnection(conn, prevErr)
if err != nil {
return err
}
}
l.mu.Lock()
if newConn != nil {
l.conn = newConn
}
l.remote = pb.NewLeaseClient(l.conn)
l.mu.Unlock()
serr := l.newStream()
if serr != nil {
return serr
}
return nil
}
func (l *lessor) newStream() error {
sctx, cancel := context.WithCancel(l.stopCtx)
stream, err := l.getRemote().LeaseKeepAlive(sctx)
if err != nil {
cancel()
return err
}
l.mu.Lock()
defer l.mu.Unlock()
if l.stream != nil && l.streamCancel != nil {
l.stream.CloseSend()
l.streamCancel()
}
l.streamCancel = cancel
l.stream = stream
return nil
}
func (ka *keepAlive) Close() {
close(ka.donec)
for _, ch := range ka.chs {
close(ch)
}
}
// cancelWhenStop calls cancel when the given stopc fires. It returns a done chan. done
// should be closed when the work is finished. When done fires, cancelWhenStop will release
// its internal resource.
func cancelWhenStop(cancel context.CancelFunc, stopc <-chan struct{}) chan<- struct{} {
done := make(chan struct{}, 1)
go func() {
select {
case <-stopc:
case <-done:
}
cancel()
}()
return done
}
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