[VOL-4291] OfAgent changes for gRPC migration
Change-Id: I8da1db6df49d478ef24ec8f9bd719e9692f48a7f
diff --git a/vendor/github.com/opencord/voltha-lib-go/v7/pkg/db/kvstore/etcdclient.go b/vendor/github.com/opencord/voltha-lib-go/v7/pkg/db/kvstore/etcdclient.go
new file mode 100644
index 0000000..6ca5329
--- /dev/null
+++ b/vendor/github.com/opencord/voltha-lib-go/v7/pkg/db/kvstore/etcdclient.go
@@ -0,0 +1,474 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * 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 kvstore
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "os"
+ "strconv"
+ "sync"
+ "time"
+
+ "github.com/opencord/voltha-lib-go/v7/pkg/log"
+ v3Client "go.etcd.io/etcd/clientv3"
+ v3rpcTypes "go.etcd.io/etcd/etcdserver/api/v3rpc/rpctypes"
+)
+
+const (
+ poolCapacityEnvName = "VOLTHA_ETCD_CLIENT_POOL_CAPACITY"
+ maxUsageEnvName = "VOLTHA_ETCD_CLIENT_MAX_USAGE"
+)
+
+const (
+ defaultMaxPoolCapacity = 1000 // Default size of an Etcd Client pool
+ defaultMaxPoolUsage = 100 // Maximum concurrent request an Etcd Client is allowed to process
+)
+
+// EtcdClient represents the Etcd KV store client
+type EtcdClient struct {
+ pool EtcdClientAllocator
+ watchedChannels sync.Map
+ watchedClients map[string]*v3Client.Client
+ watchedClientsLock sync.RWMutex
+}
+
+// NewEtcdCustomClient returns a new client for the Etcd KV store allowing
+// the called to specify etcd client configuration
+func NewEtcdCustomClient(ctx context.Context, addr string, timeout time.Duration, level log.LogLevel) (*EtcdClient, error) {
+ // Get the capacity and max usage from the environment
+ capacity := defaultMaxPoolCapacity
+ maxUsage := defaultMaxPoolUsage
+ if capacityStr, present := os.LookupEnv(poolCapacityEnvName); present {
+ if val, err := strconv.Atoi(capacityStr); err == nil {
+ capacity = val
+ logger.Infow(ctx, "env-variable-set", log.Fields{"pool-capacity": capacity})
+ } else {
+ logger.Warnw(ctx, "invalid-capacity-value", log.Fields{"error": err, "capacity": capacityStr})
+ }
+ }
+ if maxUsageStr, present := os.LookupEnv(maxUsageEnvName); present {
+ if val, err := strconv.Atoi(maxUsageStr); err == nil {
+ maxUsage = val
+ logger.Infow(ctx, "env-variable-set", log.Fields{"max-usage": maxUsage})
+ } else {
+ logger.Warnw(ctx, "invalid-max-usage-value", log.Fields{"error": err, "max-usage": maxUsageStr})
+ }
+ }
+
+ var err error
+
+ pool, err := NewRoundRobinEtcdClientAllocator([]string{addr}, timeout, capacity, maxUsage, level)
+ if err != nil {
+ logger.Errorw(ctx, "failed-to-create-rr-client", log.Fields{
+ "error": err,
+ })
+ }
+
+ logger.Infow(ctx, "etcd-pool-created", log.Fields{"capacity": capacity, "max-usage": maxUsage})
+
+ return &EtcdClient{pool: pool,
+ watchedClients: make(map[string]*v3Client.Client),
+ }, nil
+}
+
+// NewEtcdClient returns a new client for the Etcd KV store
+func NewEtcdClient(ctx context.Context, addr string, timeout time.Duration, level log.LogLevel) (*EtcdClient, error) {
+ return NewEtcdCustomClient(ctx, addr, timeout, level)
+}
+
+// IsConnectionUp returns whether the connection to the Etcd KV store is up. If a timeout occurs then
+// it is assumed the connection is down or unreachable.
+func (c *EtcdClient) IsConnectionUp(ctx context.Context) bool {
+ // Let's try to get a non existent key. If the connection is up then there will be no error returned.
+ if _, err := c.Get(ctx, "non-existent-key"); err != nil {
+ return false
+ }
+ return true
+}
+
+// List returns an array of key-value pairs with key as a prefix. Timeout defines how long the function will
+// wait for a response
+func (c *EtcdClient) List(ctx context.Context, key string) (map[string]*KVPair, error) {
+ client, err := c.pool.Get(ctx)
+ if err != nil {
+ return nil, err
+ }
+ defer c.pool.Put(client)
+ resp, err := client.Get(ctx, key, v3Client.WithPrefix())
+
+ if err != nil {
+ logger.Error(ctx, err)
+ return nil, err
+ }
+ m := make(map[string]*KVPair)
+ for _, ev := range resp.Kvs {
+ m[string(ev.Key)] = NewKVPair(string(ev.Key), ev.Value, "", ev.Lease, ev.Version)
+ }
+ return m, nil
+}
+
+// Get returns a key-value pair for a given key. Timeout defines how long the function will
+// wait for a response
+func (c *EtcdClient) Get(ctx context.Context, key string) (*KVPair, error) {
+ client, err := c.pool.Get(ctx)
+ if err != nil {
+ return nil, err
+ }
+ defer c.pool.Put(client)
+
+ attempt := 0
+
+startLoop:
+ for {
+ resp, err := client.Get(ctx, key)
+ if err != nil {
+ switch err {
+ case context.Canceled:
+ logger.Warnw(ctx, "context-cancelled", log.Fields{"error": err})
+ case context.DeadlineExceeded:
+ logger.Warnw(ctx, "context-deadline-exceeded", log.Fields{"error": err, "context": ctx})
+ case v3rpcTypes.ErrEmptyKey:
+ logger.Warnw(ctx, "etcd-client-error", log.Fields{"error": err})
+ case v3rpcTypes.ErrLeaderChanged,
+ v3rpcTypes.ErrGRPCNoLeader,
+ v3rpcTypes.ErrTimeout,
+ v3rpcTypes.ErrTimeoutDueToLeaderFail,
+ v3rpcTypes.ErrTimeoutDueToConnectionLost:
+ // Retry for these server errors
+ attempt += 1
+ if er := backoff(ctx, attempt); er != nil {
+ logger.Warnw(ctx, "get-retries-failed", log.Fields{"key": key, "error": er, "attempt": attempt})
+ return nil, err
+ }
+ logger.Warnw(ctx, "retrying-get", log.Fields{"key": key, "error": err, "attempt": attempt})
+ goto startLoop
+ default:
+ logger.Warnw(ctx, "etcd-server-error", log.Fields{"error": err})
+ }
+ return nil, err
+ }
+
+ for _, ev := range resp.Kvs {
+ // Only one value is returned
+ return NewKVPair(string(ev.Key), ev.Value, "", ev.Lease, ev.Version), nil
+ }
+ return nil, nil
+ }
+}
+
+// Put writes a key-value pair to the KV store. Value can only be a string or []byte since the etcd API
+// accepts only a string as a value for a put operation. Timeout defines how long the function will
+// wait for a response
+func (c *EtcdClient) Put(ctx context.Context, key string, value interface{}) error {
+
+ // Validate that we can convert value to a string as etcd API expects a string
+ var val string
+ var err error
+ if val, err = ToString(value); err != nil {
+ return fmt.Errorf("unexpected-type-%T", value)
+ }
+
+ client, err := c.pool.Get(ctx)
+ if err != nil {
+ return err
+ }
+ defer c.pool.Put(client)
+
+ attempt := 0
+startLoop:
+ for {
+ _, err = client.Put(ctx, key, val)
+ if err != nil {
+ switch err {
+ case context.Canceled:
+ logger.Warnw(ctx, "context-cancelled", log.Fields{"error": err})
+ case context.DeadlineExceeded:
+ logger.Warnw(ctx, "context-deadline-exceeded", log.Fields{"error": err, "context": ctx})
+ case v3rpcTypes.ErrEmptyKey:
+ logger.Warnw(ctx, "etcd-client-error", log.Fields{"error": err})
+ case v3rpcTypes.ErrLeaderChanged,
+ v3rpcTypes.ErrGRPCNoLeader,
+ v3rpcTypes.ErrTimeout,
+ v3rpcTypes.ErrTimeoutDueToLeaderFail,
+ v3rpcTypes.ErrTimeoutDueToConnectionLost:
+ // Retry for these server errors
+ attempt += 1
+ if er := backoff(ctx, attempt); er != nil {
+ logger.Warnw(ctx, "put-retries-failed", log.Fields{"key": key, "error": er, "attempt": attempt})
+ return err
+ }
+ logger.Warnw(ctx, "retrying-put", log.Fields{"key": key, "error": err, "attempt": attempt})
+ goto startLoop
+ default:
+ logger.Warnw(ctx, "etcd-server-error", log.Fields{"error": err})
+ }
+ return err
+ }
+ return nil
+ }
+}
+
+// Delete removes a key from the KV store. Timeout defines how long the function will
+// wait for a response
+func (c *EtcdClient) Delete(ctx context.Context, key string) error {
+ client, err := c.pool.Get(ctx)
+ if err != nil {
+ return err
+ }
+ defer c.pool.Put(client)
+
+ attempt := 0
+startLoop:
+ for {
+ _, err = client.Delete(ctx, key)
+ if err != nil {
+ switch err {
+ case context.Canceled:
+ logger.Warnw(ctx, "context-cancelled", log.Fields{"error": err})
+ case context.DeadlineExceeded:
+ logger.Warnw(ctx, "context-deadline-exceeded", log.Fields{"error": err, "context": ctx})
+ case v3rpcTypes.ErrEmptyKey:
+ logger.Warnw(ctx, "etcd-client-error", log.Fields{"error": err})
+ case v3rpcTypes.ErrLeaderChanged,
+ v3rpcTypes.ErrGRPCNoLeader,
+ v3rpcTypes.ErrTimeout,
+ v3rpcTypes.ErrTimeoutDueToLeaderFail,
+ v3rpcTypes.ErrTimeoutDueToConnectionLost:
+ // Retry for these server errors
+ attempt += 1
+ if er := backoff(ctx, attempt); er != nil {
+ logger.Warnw(ctx, "delete-retries-failed", log.Fields{"key": key, "error": er, "attempt": attempt})
+ return err
+ }
+ logger.Warnw(ctx, "retrying-delete", log.Fields{"key": key, "error": err, "attempt": attempt})
+ goto startLoop
+ default:
+ logger.Warnw(ctx, "etcd-server-error", log.Fields{"error": err})
+ }
+ return err
+ }
+ logger.Debugw(ctx, "key(s)-deleted", log.Fields{"key": key})
+ return nil
+ }
+}
+
+func (c *EtcdClient) DeleteWithPrefix(ctx context.Context, prefixKey string) error {
+
+ client, err := c.pool.Get(ctx)
+ if err != nil {
+ return err
+ }
+ defer c.pool.Put(client)
+
+ //delete the prefix
+ if _, err := client.Delete(ctx, prefixKey, v3Client.WithPrefix()); err != nil {
+ logger.Errorw(ctx, "failed-to-delete-prefix-key", log.Fields{"key": prefixKey, "error": err})
+ return err
+ }
+ logger.Debugw(ctx, "key(s)-deleted", log.Fields{"key": prefixKey})
+ return nil
+}
+
+// Watch provides the watch capability on a given key. It returns a channel onto which the callee needs to
+// listen to receive Events.
+func (c *EtcdClient) Watch(ctx context.Context, key string, withPrefix bool) chan *Event {
+ var err error
+ // Reuse the Etcd client when multiple callees are watching the same key.
+ c.watchedClientsLock.Lock()
+ client, exist := c.watchedClients[key]
+ if !exist {
+ client, err = c.pool.Get(ctx)
+ if err != nil {
+ logger.Errorw(ctx, "failed-to-an-etcd-client", log.Fields{"key": key, "error": err})
+ c.watchedClientsLock.Unlock()
+ return nil
+ }
+ c.watchedClients[key] = client
+ }
+ c.watchedClientsLock.Unlock()
+
+ w := v3Client.NewWatcher(client)
+ ctx, cancel := context.WithCancel(ctx)
+ var channel v3Client.WatchChan
+ if withPrefix {
+ channel = w.Watch(ctx, key, v3Client.WithPrefix())
+ } else {
+ channel = w.Watch(ctx, key)
+ }
+
+ // Create a new channel
+ ch := make(chan *Event, maxClientChannelBufferSize)
+
+ // Keep track of the created channels so they can be closed when required
+ channelMap := make(map[chan *Event]v3Client.Watcher)
+ channelMap[ch] = w
+ channelMaps := c.addChannelMap(key, channelMap)
+
+ // Changing the log field (from channelMaps) as the underlying logger cannot format the map of channels into a
+ // json format.
+ logger.Debugw(ctx, "watched-channels", log.Fields{"len": len(channelMaps)})
+ // Launch a go routine to listen for updates
+ go c.listenForKeyChange(ctx, channel, ch, cancel)
+
+ return ch
+
+}
+
+func (c *EtcdClient) addChannelMap(key string, channelMap map[chan *Event]v3Client.Watcher) []map[chan *Event]v3Client.Watcher {
+ var channels interface{}
+ var exists bool
+
+ if channels, exists = c.watchedChannels.Load(key); exists {
+ channels = append(channels.([]map[chan *Event]v3Client.Watcher), channelMap)
+ } else {
+ channels = []map[chan *Event]v3Client.Watcher{channelMap}
+ }
+ c.watchedChannels.Store(key, channels)
+
+ return channels.([]map[chan *Event]v3Client.Watcher)
+}
+
+func (c *EtcdClient) removeChannelMap(key string, pos int) []map[chan *Event]v3Client.Watcher {
+ var channels interface{}
+ var exists bool
+
+ if channels, exists = c.watchedChannels.Load(key); exists {
+ channels = append(channels.([]map[chan *Event]v3Client.Watcher)[:pos], channels.([]map[chan *Event]v3Client.Watcher)[pos+1:]...)
+ c.watchedChannels.Store(key, channels)
+ }
+
+ return channels.([]map[chan *Event]v3Client.Watcher)
+}
+
+func (c *EtcdClient) getChannelMaps(key string) ([]map[chan *Event]v3Client.Watcher, bool) {
+ var channels interface{}
+ var exists bool
+
+ channels, exists = c.watchedChannels.Load(key)
+
+ if channels == nil {
+ return nil, exists
+ }
+
+ return channels.([]map[chan *Event]v3Client.Watcher), exists
+}
+
+// CloseWatch closes a specific watch. Both the key and the channel are required when closing a watch as there
+// may be multiple listeners on the same key. The previously created channel serves as a key
+func (c *EtcdClient) CloseWatch(ctx context.Context, key string, ch chan *Event) {
+ // Get the array of channels mapping
+ var watchedChannels []map[chan *Event]v3Client.Watcher
+ var ok bool
+
+ if watchedChannels, ok = c.getChannelMaps(key); !ok {
+ logger.Warnw(ctx, "key-has-no-watched-channels", log.Fields{"key": key})
+ return
+ }
+ // Look for the channels
+ var pos = -1
+ for i, chMap := range watchedChannels {
+ if t, ok := chMap[ch]; ok {
+ logger.Debug(ctx, "channel-found")
+ // Close the etcd watcher before the client channel. This should close the etcd channel as well
+ if err := t.Close(); err != nil {
+ logger.Errorw(ctx, "watcher-cannot-be-closed", log.Fields{"key": key, "error": err})
+ }
+ pos = i
+ break
+ }
+ }
+
+ channelMaps, _ := c.getChannelMaps(key)
+ // Remove that entry if present
+ if pos >= 0 {
+ channelMaps = c.removeChannelMap(key, pos)
+ }
+
+ // If we don't have any keys being watched then return the Etcd client to the pool
+ if len(channelMaps) == 0 {
+ c.watchedClientsLock.Lock()
+ // Sanity
+ if client, ok := c.watchedClients[key]; ok {
+ c.pool.Put(client)
+ delete(c.watchedClients, key)
+ }
+ c.watchedClientsLock.Unlock()
+ }
+ logger.Infow(ctx, "watcher-channel-exiting", log.Fields{"key": key, "channel": channelMaps})
+}
+
+func (c *EtcdClient) listenForKeyChange(ctx context.Context, channel v3Client.WatchChan, ch chan<- *Event, cancel context.CancelFunc) {
+ logger.Debug(ctx, "start-listening-on-channel ...")
+ defer cancel()
+ defer close(ch)
+ for resp := range channel {
+ for _, ev := range resp.Events {
+ ch <- NewEvent(getEventType(ev), ev.Kv.Key, ev.Kv.Value, ev.Kv.Version)
+ }
+ }
+ logger.Debug(ctx, "stop-listening-on-channel ...")
+}
+
+func getEventType(event *v3Client.Event) int {
+ switch event.Type {
+ case v3Client.EventTypePut:
+ return PUT
+ case v3Client.EventTypeDelete:
+ return DELETE
+ }
+ return UNKNOWN
+}
+
+// Close closes all the connection in the pool store client
+func (c *EtcdClient) Close(ctx context.Context) {
+ logger.Debug(ctx, "closing-etcd-pool")
+ c.pool.Close(ctx)
+}
+
+// The APIs below are not used
+var errUnimplemented = errors.New("deprecated")
+
+// Reserve is deprecated
+func (c *EtcdClient) Reserve(ctx context.Context, key string, value interface{}, ttl time.Duration) (interface{}, error) {
+ return nil, errUnimplemented
+}
+
+// ReleaseAllReservations is deprecated
+func (c *EtcdClient) ReleaseAllReservations(ctx context.Context) error {
+ return errUnimplemented
+}
+
+// ReleaseReservation is deprecated
+func (c *EtcdClient) ReleaseReservation(ctx context.Context, key string) error {
+ return errUnimplemented
+}
+
+// RenewReservation is deprecated
+func (c *EtcdClient) RenewReservation(ctx context.Context, key string) error {
+ return errUnimplemented
+}
+
+// AcquireLock is deprecated
+func (c *EtcdClient) AcquireLock(ctx context.Context, lockName string, timeout time.Duration) error {
+ return errUnimplemented
+}
+
+// ReleaseLock is deprecated
+func (c *EtcdClient) ReleaseLock(lockName string) error {
+ return errUnimplemented
+}