Clientv3 (retry) logs should use the configured logger.

clientv3 logs (especially tests) were poluted with unattributed to testing.T log lines:

```
{"level":"warn","ts":"2021-04-29T12:42:11.055+0200","logger":"etcd-client","caller":"v3/retry_interceptor.go:64","msg":"retrying of unary invoker failed","target":"etcd-endpoints://0xc0000fafc0/#initially=[unix://localhost:m10]","attempt":0,"error":"rpc error: code = ResourceExhausted desc = etcdserver: mvcc: database space exceeded"}
```

The reasons were 2 fold:
  - Interceptors were copying logger before "WithLogger" could modify it.
  - We were not propagating the loggers in a few testing contexts.

client/v3/client.go

@@ -215,8 +215,8 @@ func (c *Client) dialSetupOpts(creds grpccredentials.TransportCredentials, dopts
 	opts = append(opts,
 		// Disable stream retry by default since go-grpc-middleware/retry does not support client streams.
 		// Streams that are safe to retry are enabled individually.
-		grpc.WithStreamInterceptor(c.streamClientInterceptor(c.lg, withMax(0), rrBackoff)),
-		grpc.WithUnaryInterceptor(c.unaryClientInterceptor(c.lg, withMax(defaultUnaryMaxRetries), rrBackoff)),
+		grpc.WithStreamInterceptor(c.streamClientInterceptor(withMax(0), rrBackoff)),
+		grpc.WithUnaryInterceptor(c.unaryClientInterceptor(withMax(defaultUnaryMaxRetries), rrBackoff)),
 	)
 
 	return opts, nil

client/v3/retry_interceptor.go

@@ -35,7 +35,7 @@ import (
 //
 // The default configuration of the interceptor is to not retry *at all*. This behaviour can be
 // changed through options (e.g. WithMax) on creation of the interceptor or on call (through grpc.CallOptions).
-func (c *Client) unaryClientInterceptor(logger *zap.Logger, optFuncs ...retryOption) grpc.UnaryClientInterceptor {
+func (c *Client) unaryClientInterceptor(optFuncs ...retryOption) grpc.UnaryClientInterceptor {
 	intOpts := reuseOrNewWithCallOptions(defaultOptions, optFuncs)
 	return func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
 		ctx = withVersion(ctx)
@@ -50,7 +50,7 @@ func (c *Client) unaryClientInterceptor(logger *zap.Logger, optFuncs ...retryOpt
 			if err := waitRetryBackoff(ctx, attempt, callOpts); err != nil {
 				return err
 			}
-			logger.Debug(
+			c.GetLogger().Debug(
 				"retrying of unary invoker",
 				zap.String("target", cc.Target()),
 				zap.Uint("attempt", attempt),
@@ -59,7 +59,7 @@ func (c *Client) unaryClientInterceptor(logger *zap.Logger, optFuncs ...retryOpt
 			if lastErr == nil {
 				return nil
 			}
-			logger.Warn(
+			c.GetLogger().Warn(
 				"retrying of unary invoker failed",
 				zap.String("target", cc.Target()),
 				zap.Uint("attempt", attempt),
@@ -82,7 +82,7 @@ func (c *Client) unaryClientInterceptor(logger *zap.Logger, optFuncs ...retryOpt
 
 				gterr := c.getToken(ctx)
 				if gterr != nil {
-					logger.Warn(
+					c.GetLogger().Warn(
 						"retrying of unary invoker failed to fetch new auth token",
 						zap.String("target", cc.Target()),
 						zap.Error(gterr),
@@ -107,7 +107,7 @@ func (c *Client) unaryClientInterceptor(logger *zap.Logger, optFuncs ...retryOpt
 // Retry logic is available *only for ServerStreams*, i.e. 1:n streams, as the internal logic needs
 // to buffer the messages sent by the client. If retry is enabled on any other streams (ClientStreams,
 // BidiStreams), the retry interceptor will fail the call.
-func (c *Client) streamClientInterceptor(logger *zap.Logger, optFuncs ...retryOption) grpc.StreamClientInterceptor {
+func (c *Client) streamClientInterceptor(optFuncs ...retryOption) grpc.StreamClientInterceptor {
 	intOpts := reuseOrNewWithCallOptions(defaultOptions, optFuncs)
 	return func(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {
 		ctx = withVersion(ctx)
@@ -117,7 +117,7 @@ func (c *Client) streamClientInterceptor(logger *zap.Logger, optFuncs ...retryOp
 			// equal to c.Username != "" && c.Password != ""
 			err := c.getToken(ctx)
 			if err != nil && rpctypes.Error(err) != rpctypes.ErrAuthNotEnabled {
-				logger.Error("clientv3/retry_interceptor: getToken failed", zap.Error(err))
+				c.GetLogger().Error("clientv3/retry_interceptor: getToken failed", zap.Error(err))
 				return nil, err
 			}
 		}
@@ -132,7 +132,7 @@ func (c *Client) streamClientInterceptor(logger *zap.Logger, optFuncs ...retryOp
 		}
 		newStreamer, err := streamer(ctx, desc, cc, method, grpcOpts...)
 		if err != nil {
-			logger.Error("streamer failed to create ClientStream", zap.Error(err))
+			c.GetLogger().Error("streamer failed to create ClientStream", zap.Error(err))
 			return nil, err // TODO(mwitkow): Maybe dial and transport errors should be retriable?
 		}
 		retryingStreamer := &serverStreamingRetryingStream{

client/v3/snapshot/v3_snapshot.go

@@ -56,6 +56,8 @@ func Save(ctx context.Context, lg *zap.Logger, cfg clientv3.Config, dbPath strin
 	}
 	defer cli.Close()
 
+	cli = cli.WithLogger(lg.Named("client"))
+
 	partpath := dbPath + ".part"
 	defer os.RemoveAll(partpath)
 

etcdctl/ctlv3/command/ep_command.go

@@ -120,6 +120,7 @@ func epHealthCommandFunc(cmd *cobra.Command, args []string) {
 				hch <- epHealth{Ep: ep, Health: false, Error: err.Error()}
 				return
 			}
+			cli = cli.WithLogger(lg.Named("client"))
 			st := time.Now()
 			// get a random key. As long as we can get the response without an error, the
 			// endpoint is health.

server/etcdmain/grpc_proxy.go

@@ -288,7 +288,7 @@ func mustNewClient(lg *zap.Logger) *clientv3.Client {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
-	return client
+	return client.WithLogger(lg.Named("client"))
 }
 
 func mustNewProxyClient(lg *zap.Logger, tls *transport.TLSInfo) *clientv3.Client {
@@ -304,7 +304,7 @@ func mustNewProxyClient(lg *zap.Logger, tls *transport.TLSInfo) *clientv3.Client
 		os.Exit(1)
 	}
 	lg.Info("create proxy client", zap.String("grpcProxyAdvertiseClientURL", grpcProxyAdvertiseClientURL))
-	return client
+	return client.WithLogger(lg.Named("client"))
 }
 
 func newProxyClientCfg(lg *zap.Logger, eps []string, tls *transport.TLSInfo) (*clientv3.Config, error) {