xds: move balancer/resolver registation to package xds (#3640)

examples/features/xds/README.md

@@ -9,13 +9,11 @@ hello world
 example](https://github.com/grpc/grpc-go/tree/master/examples/helloworld). The
 server replies with responses including its hostname.
 
-**Note** that xDS support is incomplete and experimental, with limited
-compatibility.
-
 ## xDS environment setup
 
-This example doesn't include instuctions to setup xDS environment. Please
-refer to documentation specific for your xDS management server.
+This example doesn't include instructions to setup xDS environment. Please refer
+to documentation specific for your xDS management server. Examples will be added
+later.
 
 The client also needs a bootstrap file. See [gRFC
 A27](https://github.com/grpc/proposal/blob/master/A27-xds-global-load-balancing.md#xdsclient-and-bootstrap-file)
@@ -26,7 +24,7 @@ for the bootstrap format.
 The client application needs to import the xDS package to install the resolver and balancers:
 
 ```go
-_ "google.golang.org/grpc/xds/experimental" // To install the xds resolvers and balancers.
+_ "google.golang.org/grpc/xds" // To install the xds resolvers and balancers.
 ```
 
 Then, use `xds` target scheme for the ClientConn.

examples/features/xds/client/main.go

@@ -31,6 +31,7 @@ import (
 	"google.golang.org/grpc"
 	pb "google.golang.org/grpc/examples/helloworld/helloworld"
 
+	// TODO: change this to xds after the xds package is released.
 	_ "google.golang.org/grpc/xds/experimental" // To install the xds resolvers and balancers.
 )
 

interop/xds/client/client.go

@@ -31,7 +31,7 @@ import (
 	"google.golang.org/grpc/grpclog"
 	testpb "google.golang.org/grpc/interop/grpc_testing"
 	"google.golang.org/grpc/peer"
-	_ "google.golang.org/grpc/xds/experimental"
+	_ "google.golang.org/grpc/xds"
 )
 
 type statsWatcherKey struct {

xds/experimental/xds_experimental.go

@@ -16,13 +16,14 @@
  *
  */
 
-// Package experimental contains xds implementation, still in experimental
-// state. Users only need to import this package to get all xds functionality.
-// Things are expected to change fast until we get to a stable state, at
-// which point, all this will be moved to the xds package.
+// Package experimental contains xds implementation. Users only need to import
+// this package to get all xds functionality.
+//
+// Deprecated: import package xds instead.
 package experimental
 
+// TODO: remove this package after one release.
+
 import (
-	_ "google.golang.org/grpc/xds/internal/balancer" // Register the balancers.
-	_ "google.golang.org/grpc/xds/internal/resolver" // Register the xds_resolver
+	_ "google.golang.org/grpc/xds" // Register the balancers and resolvers.
 )

xds/xds.go

@@ -0,0 +1,29 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * 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 xds contains xds implementation. Users need to import this package to
+// get all xds functionality.
+//
+// See https://github.com/grpc/grpc-go/tree/master/examples/features/xds for
+// example.
+package xds
+
+import (
+	_ "google.golang.org/grpc/xds/internal/balancer" // Register the balancers.
+	_ "google.golang.org/grpc/xds/internal/resolver" // Register the xds_resolver
+)