Golang util.IsEtcdNotFound函數代碼示例

// handleMaster performs one loop of master locking.
// on success it returns <master>, nil
// on error it returns "", err
// in situations where you should try again due to concurrent state changes (e.g. another actor simultaneously acquiring the lock)
// it returns "", nil
func (e *etcdMasterElector) handleMaster(path, id string, ttl uint64) (string, error) {
	res, err := e.etcd.Get(context.TODO(), path, nil)

	// Unexpected error, bail out
	if err != nil && !etcdutil.IsEtcdNotFound(err) {
		return "", err
	}

	// There is no master, try to become the master.
	if err != nil && etcdutil.IsEtcdNotFound(err) {
		return e.becomeMaster(path, id, ttl)
	}

	// This should never happen.
	if res.Node == nil {
		return "", fmt.Errorf("unexpected response: %#v", res)
	}

	// We're not the master, just return the current value
	if res.Node.Value != id {
		return res.Node.Value, nil
	}

	// We are the master, try to extend out lease
	return e.extendMaster(path, id, ttl, res)
}

func Store(api etcd.KeysAPI, path string, ttl time.Duration) frameworkid.Storage {
	// TODO(jdef) validate Config
	return &storage{
		LookupFunc: func(ctx context.Context) (string, error) {
			if response, err := api.Get(ctx, path, nil); err != nil {
				if !etcdutil.IsEtcdNotFound(err) {
					return "", fmt.Errorf("unexpected failure attempting to load framework ID from etcd: %v", err)
				}
			} else {
				return response.Node.Value, nil
			}
			return "", nil
		},
		RemoveFunc: func(ctx context.Context) (err error) {
			if _, err = api.Delete(ctx, path, &etcd.DeleteOptions{Recursive: true}); err != nil {
				if !etcdutil.IsEtcdNotFound(err) {
					return fmt.Errorf("failed to delete framework ID from etcd: %v", err)
				}
			}
			return
		},
		StoreFunc: func(ctx context.Context, id string) (err error) {
			_, err = api.Set(ctx, path, id, &etcd.SetOptions{TTL: ttl})
			return
		},
	}
}

// Implements storage.Interface.
func (h *etcdHelper) Delete(ctx context.Context, key string, out runtime.Object, preconditions *storage.Preconditions) error {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	key = h.prefixEtcdKey(key)
	v, err := conversion.EnforcePtr(out)
	if err != nil {
		panic("unable to convert output object to pointer")
	}

	if preconditions == nil {
		startTime := time.Now()
		response, err := h.etcdKeysAPI.Delete(ctx, key, nil)
		metrics.RecordEtcdRequestLatency("delete", getTypeName(out), startTime)
		if !etcdutil.IsEtcdNotFound(err) {
			// if the object that existed prior to the delete is returned by etcd, update the out object.
			if err != nil || response.PrevNode != nil {
				_, _, err = h.extractObj(response, err, out, false, true)
			}
		}
		return toStorageErr(err, key, 0)
	}

	// Check the preconditions match.
	obj := reflect.New(v.Type()).Interface().(runtime.Object)
	for {
		_, node, res, err := h.bodyAndExtractObj(ctx, key, obj, false)
		if err != nil {
			return toStorageErr(err, key, 0)
		}
		if err := checkPreconditions(key, preconditions, obj); err != nil {
			return toStorageErr(err, key, 0)
		}
		index := uint64(0)
		if node != nil {
			index = node.ModifiedIndex
		} else if res != nil {
			index = res.Index
		}
		opt := etcd.DeleteOptions{PrevIndex: index}
		startTime := time.Now()
		response, err := h.etcdKeysAPI.Delete(ctx, key, &opt)
		metrics.RecordEtcdRequestLatency("delete", getTypeName(out), startTime)
		if etcdutil.IsEtcdTestFailed(err) {
			glog.Infof("deletion of %s failed because of a conflict, going to retry", key)
		} else {
			if !etcdutil.IsEtcdNotFound(err) {
				// if the object that existed prior to the delete is returned by etcd, update the out object.
				if err != nil || response.PrevNode != nil {
					_, _, err = h.extractObj(response, err, out, false, true)
				}
			}
			return toStorageErr(err, key, 0)
		}
	}
}

// InterpretDeleteError converts a generic etcd error on a delete
// operation into the appropriate API error.
func InterpretDeleteError(err error, kind, name string) error {
	switch {
	case etcdutil.IsEtcdNotFound(err):
		return errors.NewNotFound(kind, name)
	case etcdutil.IsEtcdUnreachable(err):
		return errors.NewServerTimeout(kind, "delete", 2) // TODO: make configurable or handled at a higher level
	default:
		return err
	}
}

// TestEtcdClient verifies a client is functional.  It will attempt to
// connect to the etcd server and block until the server responds at least once, or return an
// error if the server never responded.
func TestEtcdClient(etcdClient etcdclient.Client) error {
	for i := 0; ; i++ {
		_, err := etcdclient.NewKeysAPI(etcdClient).Get(context.Background(), "/", nil)
		if err == nil || etcdutil.IsEtcdNotFound(err) {
			break
		}
		if i > 100 {
			return fmt.Errorf("could not reach etcd: %v", err)
		}
		time.Sleep(50 * time.Millisecond)
	}
	return nil
}

func TestGetNotFoundErr(t *testing.T) {
	server := etcdtesting.NewEtcdTestClientServer(t)
	defer server.Terminate(t)
	key := etcdtest.AddPrefix("/some/key")
	boguskey := etcdtest.AddPrefix("/some/boguskey")
	helper := newEtcdHelper(server.Client, testapi.Default.Codec(), key)

	var got api.Pod
	err := helper.Get(context.TODO(), boguskey, &got, false)
	if !etcdutil.IsEtcdNotFound(err) {
		t.Errorf("Unexpected reponse on key=%v, err=%v", key, err)
	}
}

// TestEtcdClient verifies a client is functional.  It will attempt to
// connect to the etcd server and block until the server responds at least once, or return an
// error if the server never responded.
func TestEtcdClient(etcdClient *etcdclient.Client) error {
	for i := 0; ; i++ {
		_, err := etcdClient.Get("/", false, false)
		if err == nil || etcdutil.IsEtcdNotFound(err) {
			break
		}
		if i > 100 {
			return fmt.Errorf("could not reach etcd: %v", err)
		}
		time.Sleep(50 * time.Millisecond)
	}
	return nil
}

func (s *SchedulerServer) fetchFrameworkID(client tools.EtcdClient) (*mesos.FrameworkID, error) {
	if s.failoverTimeout > 0 {
		if response, err := client.Get(meta.FrameworkIDKey, false, false); err != nil {
			if !etcdutil.IsEtcdNotFound(err) {
				return nil, fmt.Errorf("unexpected failure attempting to load framework ID from etcd: %v", err)
			}
			log.V(1).Infof("did not find framework ID in etcd")
		} else if response.Node.Value != "" {
			log.Infof("configuring FrameworkInfo with Id found in etcd: '%s'", response.Node.Value)
			return mutil.NewFrameworkID(response.Node.Value), nil
		}
	} else {
		//TODO(jdef) this seems like a totally hackish way to clean up the framework ID
		if _, err := client.Delete(meta.FrameworkIDKey, true); err != nil {
			if !etcdutil.IsEtcdNotFound(err) {
				return nil, fmt.Errorf("failed to delete framework ID from etcd: %v", err)
			}
			log.V(1).Infof("nothing to delete: did not find framework ID in etcd")
		}
	}
	return nil, nil
}

// Refresh reloads the RangeAllocation from etcd.
func (e *Etcd) Refresh() (*api.RangeAllocation, error) {
	e.lock.Lock()
	defer e.lock.Unlock()

	existing := &api.RangeAllocation{}
	if err := e.storage.Get(context.TODO(), e.baseKey, existing, false); err != nil {
		if etcdutil.IsEtcdNotFound(err) {
			return nil, nil
		}
		return nil, etcderr.InterpretGetError(err, e.kind, "")
	}

	return existing, nil
}

// bodyAndExtractObj performs the normal Get path to etcd, returning the parsed node and response for additional information
// about the response, like the current etcd index and the ttl.
func (h *etcdHelper) bodyAndExtractObj(ctx context.Context, key string, objPtr runtime.Object, ignoreNotFound bool) (body string, node *etcd.Node, res *etcd.Response, err error) {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	startTime := time.Now()
	response, err := h.client.Get(ctx, key, nil)
	metrics.RecordEtcdRequestLatency("get", getTypeName(objPtr), startTime)

	if err != nil && !etcdutil.IsEtcdNotFound(err) {
		return "", nil, nil, err
	}
	body, node, err = h.extractObj(response, err, objPtr, ignoreNotFound, false)
	return body, node, response, err
}

// Release tries to delete the leader lock.
func (e *Etcd) Release() {
	for i := 0; i < e.maxRetries; i++ {
		_, err := e.client.CompareAndDelete(e.key, e.value, 0)
		if err == nil {
			break
		}
		// If the value has changed, we don't hold the lease. If the key is missing we don't
		// hold the lease.
		if etcdutil.IsEtcdTestFailed(err) || etcdutil.IsEtcdNotFound(err) {
			break
		}
		utilruntime.HandleError(fmt.Errorf("unable to release %s: %v", e.key, err))
	}
}

// etcdGetInitialWatchState turns an etcd Get request into a watch equivalent
func etcdGetInitialWatchState(client *etcd.Client, key string, recursive bool, incoming chan<- *etcd.Response) (resourceVersion uint64, err error) {
	resp, err := client.Get(key, false, recursive)
	if err != nil {
		if !etcdutil.IsEtcdNotFound(err) {
			glog.Errorf("watch was unable to retrieve the current index for the provided key (%q): %v", key, err)
			return resourceVersion, err
		}
		if etcdError, ok := err.(*etcd.EtcdError); ok {
			resourceVersion = etcdError.Index
		}
		return resourceVersion, nil
	}
	resourceVersion = resp.EtcdIndex
	convertRecursiveResponse(resp.Node, resp, incoming)
	return
}

func toStorageErr(err error, key string, rv int64) error {
	if err == nil {
		return nil
	}
	switch {
	case etcdutil.IsEtcdNotFound(err):
		return storage.NewKeyNotFoundError(key, rv)
	case etcdutil.IsEtcdNodeExist(err):
		return storage.NewKeyExistsError(key, rv)
	case etcdutil.IsEtcdTestFailed(err):
		return storage.NewResourceVersionConflictsError(key, rv)
	case etcdutil.IsEtcdUnreachable(err):
		return storage.NewUnreachableError(key, rv)
	default:
		return err
	}
}

// bodyAndExtractObj performs the normal Get path to etcd, returning the parsed node and response for additional information
// about the response, like the current etcd index and the ttl.
func (h *etcdHelper) bodyAndExtractObj(ctx context.Context, key string, objPtr runtime.Object, ignoreNotFound bool) (body string, node *etcd.Node, res *etcd.Response, err error) {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	startTime := time.Now()

	opts := &etcd.GetOptions{
		Quorum: h.quorum,
	}

	response, err := h.etcdKeysAPI.Get(ctx, key, opts)
	metrics.RecordEtcdRequestLatency("get", getTypeName(objPtr), startTime)
	if err != nil && !etcdutil.IsEtcdNotFound(err) {
		return "", nil, nil, toStorageErr(err, key, 0)
	}
	body, node, err = h.extractObj(response, err, objPtr, ignoreNotFound, false)
	return body, node, response, toStorageErr(err, key, 0)
}

func (h *etcdHelper) listEtcdNode(ctx context.Context, key string) ([]*etcd.Node, uint64, error) {
	if ctx == nil {
		glog.Errorf("Context is nil")
	}
	result, err := h.client.Get(key, true, true)
	if err != nil {
		var index uint64
		if etcdError, ok := err.(*etcd.EtcdError); ok {
			index = etcdError.Index
		}
		nodes := make([]*etcd.Node, 0)
		if etcdutil.IsEtcdNotFound(err) {
			return nodes, index, nil
		} else {
			return nodes, index, err
		}
	}
	return result.Node.Nodes, result.EtcdIndex, nil
}