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filters/featureBreaker/featurebreaker.go

Index: filters/featureBreaker/featurebreaker.go
diff --git a/filters/featureBreaker/featurebreaker.go b/filters/featureBreaker/featurebreaker.go
deleted file mode 100644
index 3808209f6eba8885ceefafb9408d17865e51e015..0000000000000000000000000000000000000000
--- a/filters/featureBreaker/featurebreaker.go
+++ /dev/null
@@ -1,117 +0,0 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package featureBreaker
-
-import (
-	"errors"
-	"fmt"
-	"runtime"
-	"strings"
-	"sync"
-)
-
-// FeatureBreaker is the state-access interface for all Filter* functions in
-// this package.  A feature is the Name of some method on the filtered service.
-// So if you had:
-//   c, fb := FilterMC(...)
-//   mc := gae.GetMC(c)
-//
-// you could do:
-//   fb.BreakFeatures(memcache.ErrServerError, "Add", "Set")
-//
-// and then
-//   mc.Add(...) and mc.Set(...)
-//
-// would return the error.
-//
-// You may also pass nil as the error for BreakFeatures, and the fake will
-// provide the DefaultError which you passed to the Filter function.
-//
-// This interface can only break features which return errors.
-type FeatureBreaker interface {
-	BreakFeatures(err error, feature ...string)
-	UnbreakFeatures(feature ...string)
-}
-
-// ErrBrokenFeaturesBroken is returned from RunIfNotBroken when BrokenFeatures
-// itself isn't working correctly.
-var ErrBrokenFeaturesBroken = errors.New("featureBreaker: Unable to retrieve caller information")
-
-type state struct {
-	sync.Mutex
-
-	broken map[string]error
-
-	// defaultError is the default error to return when you call
-	// BreakFeatures(nil, ...). If this is unset and the user calls BreakFeatures
-	// with nil, BrokenFeatures will return a generic error.
-	defaultError error
-}
-
-func newState(dflt error) *state {
-	return &state{
-		broken:       map[string]error{},
-		defaultError: dflt,
-	}
-}
-
-// BreakFeatures allows you to specify an MCSingleReadWriter function name
-// to cause it to return memcache.ErrServerError. e.g.
-//
-//   m.SetBrokenFeatures("Add")
-//
-// would return memcache.ErrServerError. You can reverse this by calling
-// UnbreakFeatures("Add").
-func (s *state) BreakFeatures(err error, feature ...string) {
-	s.Lock()
-	defer s.Unlock()
-	for _, f := range feature {
-		s.broken[f] = err
-	}
-}
-
-// UnbreakFeatures is the inverse of BreakFeatures, and will return the named
-// features back to their original functionality.
-func (s *state) UnbreakFeatures(feature ...string) {
-	s.Lock()
-	defer s.Unlock()
-	for _, f := range feature {
-		delete(s.broken, f)
-	}
-}
-
-func (s *state) run(f func() error) error {
-	if s.noBrokenFeatures() {
-		return f()
-	}
-
-	pc, _, _, _ := runtime.Caller(1)
-	fullName := runtime.FuncForPC(pc).Name()
-	fullNameParts := strings.Split(fullName, ".")
-	name := fullNameParts[len(fullNameParts)-1]
-
-	s.Lock()
-	err, ok := s.broken[name]
-	dflt := s.defaultError
-	s.Unlock()
-
-	if ok {
-		if err != nil {
-			return err
-		}
-		if dflt != nil {
-			return dflt
-		}
-		return fmt.Errorf("feature %q is broken", name)
-	}
-
-	return f()
-}
-
-func (s *state) noBrokenFeatures() bool {
-	s.Lock()
-	defer s.Unlock()
-	return len(s.broken) == 0
-}