Implement check for priority

pkg/util/codeinspector/codeinspector.go

+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+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 codeinspector
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"unicode"
+)
+
+// Get all public functions (not methods) from a golang source file.
+func GetPulicFunctions(filePath string) ([]string, error) {
+	var functionNames []string
+
+	// Create the AST by parsing src.
+	fset := token.NewFileSet() // positions are relative to fset
+	f, err := parser.ParseFile(fset, filePath, nil, 0)
+	if err != nil {
+		return nil, fmt.Errorf("failed parse file to list functions: %v", err)
+	}
+
+	// Inspect the AST and print all identifiers and literals.
+	ast.Inspect(f, func(n ast.Node) bool {
+		var s string
+		switch x := n.(type) {
+		case *ast.FuncDecl:
+			s = x.Name.Name
+			// It's a function (not method), and is public, record it.
+			if x.Recv == nil && isPublic(s) {
+				functionNames = append(functionNames, s)
+			}
+		}
+		return true
+	})
+
+	return functionNames, nil
+}
+
+// Check if a given string is a public function name.
+func isPublic(myString string) bool {
+	a := []rune(myString)
+	a[0] = unicode.ToUpper(a[0])
+	return myString == string(a)
+}

plugin/pkg/scheduler/algorithm/priorities/priorities_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package priorities
 
 import (
+	"os/exec"
 	"reflect"
 	"sort"
 	"strconv"
@@ -25,6 +26,7 @@ import (
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/resource"
 	"k8s.io/kubernetes/pkg/apis/extensions"
+	"k8s.io/kubernetes/pkg/util/codeinspector"
 	"k8s.io/kubernetes/plugin/pkg/scheduler"
 	"k8s.io/kubernetes/plugin/pkg/scheduler/algorithm"
 	priorityutil "k8s.io/kubernetes/plugin/pkg/scheduler/algorithm/priorities/util"
@@ -884,3 +886,30 @@ func makeImageNode(node string, status api.NodeStatus) api.Node {
 		Status:     status,
 	}
 }
+
+func TestPriorityRegistered(t *testing.T) {
+	var functionNames []string
+
+	files := []string{"priorities.go", "node_affinity.go", "selector_spreading.go"}
+
+	for _, filePath := range files {
+		functions, err := codeinspector.GetPulicFunctions(filePath)
+		if err == nil {
+			functionNames = append(functionNames, functions...)
+		} else {
+			t.Errorf("unexpected error when parsing %s", filePath)
+		}
+	}
+
+	for _, funcionName := range functionNames {
+		err := exec.Command("grep", "-rl", funcionName, "./../../algorithmprovider/defaults/defaults.go", "./../../factory/plugins.go").Run()
+		if err != nil {
+			switch err.Error() {
+			case "exit status 2":
+				t.Errorf("unexpected error when checking %s", funcionName)
+			case "exit status 1":
+				t.Errorf("priority %s is implemented but seems not registered in any place", funcionName)
+			}
+		}
+	}
+}