Allow ValidationErrorList to be filtered

pkg/api/errors/validation.go

@@ -20,6 +20,8 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util/errors"
+
 	"github.com/davecgh/go-spew/spew"
 	"github.com/golang/glog"
 )
@@ -155,3 +157,37 @@ func (list ValidationErrorList) Prefix(prefix string) ValidationErrorList {
 func (list ValidationErrorList) PrefixIndex(index int) ValidationErrorList {
 	return list.Prefix(fmt.Sprintf("[%d]", index))
 }
+
+// NewValidationErrorFieldPrefixMatcher returns an errors.Matcher that returns true
+// if the provided error is a ValidationError and has the provided ValidationErrorType.
+func NewValidationErrorTypeMatcher(t ValidationErrorType) errors.Matcher {
+	return func(err error) bool {
+		if e, ok := err.(*ValidationError); ok {
+			return e.Type == t
+		}
+		return false
+	}
+}
+
+// NewValidationErrorFieldPrefixMatcher returns an errors.Matcher that returns true
+// if the provided error is a ValidationError and has a field with the provided
+// prefix.
+func NewValidationErrorFieldPrefixMatcher(prefix string) errors.Matcher {
+	return func(err error) bool {
+		if e, ok := err.(*ValidationError); ok {
+			return strings.HasPrefix(e.Field, prefix)
+		}
+		return false
+	}
+}
+
+// Filter removes items from the ValidationErrorList that match the provided fns.
+func (list ValidationErrorList) Filter(fns ...errors.Matcher) ValidationErrorList {
+	err := errors.FilterOut(errors.NewAggregate(list), fns...)
+	if err == nil {
+		return nil
+	}
+	// FilterOut that takes an Aggregate returns an Aggregate
+	agg := err.(errors.Aggregate)
+	return ValidationErrorList(agg.Errors())
+}

pkg/api/errors/validation_test.go

@@ -93,6 +93,32 @@ func TestValidationErrorUsefulMessage(t *testing.T) {
 	}
 }
 
+func TestErrListFilter(t *testing.T) {
+	list := ValidationErrorList{
+		NewFieldInvalid("test.field", "", ""),
+		NewFieldInvalid("field.test", "", ""),
+		NewFieldDuplicate("test", "value"),
+	}
+	if len(list.Filter(NewValidationErrorTypeMatcher(ValidationErrorTypeDuplicate))) != 2 {
+		t.Errorf("should not filter")
+	}
+	if len(list.Filter(NewValidationErrorTypeMatcher(ValidationErrorTypeInvalid))) != 1 {
+		t.Errorf("should filter")
+	}
+	if len(list.Filter(NewValidationErrorFieldPrefixMatcher("test"))) != 1 {
+		t.Errorf("should filter")
+	}
+	if len(list.Filter(NewValidationErrorFieldPrefixMatcher("test."))) != 2 {
+		t.Errorf("should filter")
+	}
+	if len(list.Filter(NewValidationErrorFieldPrefixMatcher(""))) != 0 {
+		t.Errorf("should filter")
+	}
+	if len(list.Filter(NewValidationErrorFieldPrefixMatcher("field."), NewValidationErrorTypeMatcher(ValidationErrorTypeDuplicate))) != 1 {
+		t.Errorf("should filter")
+	}
+}
+
 func TestErrListPrefix(t *testing.T) {
 	testCases := []struct {
 		Err      *ValidationError