Move grpctrace examples from comment to code

CHANGELOG.md

@@ -45,6 +45,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Use `global.Handle` for span export errors in the OTLP exporter. (#946)
 - Correct Go language formatting in the README documentation. (#961)
 - Remove default SDK dependencies from the `go.opentelemetry.io/otel/api` package. (#977)
+- Move documented examples for `go.opentelemetry.io/otel/instrumentation/grpctrace` interceptors into Go example tests. (#984)
 
 ## [0.9.0] - 2020-07-20
 

instrumentation/grpctrace/example_interceptor_test.go

@@ -0,0 +1,51 @@
+// Copyright The OpenTelemetry 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 grpctrace
+
+import (
+	"google.golang.org/grpc"
+
+	"go.opentelemetry.io/otel/api/global"
+)
+
+func ExampleStreamClientInterceptor() {
+	tracer := global.Tracer("client-instrumentation")
+	_, _ = grpc.Dial(
+		"localhost",
+		grpc.WithStreamInterceptor(StreamClientInterceptor(tracer)),
+	)
+}
+
+func ExampleUnaryClientInterceptor() {
+	tracer := global.Tracer("client-instrumentation")
+	_, _ = grpc.Dial(
+		"localhost",
+		grpc.WithUnaryInterceptor(UnaryClientInterceptor(tracer)),
+	)
+}
+
+func ExampleStreamServerInterceptor() {
+	tracer := global.Tracer("server-instrumentation")
+	_ = grpc.NewServer(
+		grpc.StreamInterceptor(StreamServerInterceptor(tracer)),
+	)
+}
+
+func ExampleUnaryServerInterceptor() {
+	tracer := global.Tracer("server-instrumentation")
+	_ = grpc.NewServer(
+		grpc.UnaryInterceptor(UnaryServerInterceptor(tracer)),
+	)
+}

instrumentation/grpctrace/interceptor.go

@@ -63,12 +63,6 @@ var (
 
 // UnaryClientInterceptor returns a grpc.UnaryClientInterceptor suitable
 // for use in a grpc.Dial call.
-//
-// For example:
-//     tracer := global.Tracer("client-tracer")
-//     s := grpc.NewServer(
-//         grpc.WithUnaryInterceptor(grpctrace.UnaryClientInterceptor(tracer)),
-//         ...,  // (existing DialOptions))
 func UnaryClientInterceptor(tracer trace.Tracer) grpc.UnaryClientInterceptor {
 	return func(
 		ctx context.Context,
@@ -242,12 +236,6 @@ func (w *clientStream) sendStreamEvent(eventType streamEventType, err error) {
 
 // StreamClientInterceptor returns a grpc.StreamClientInterceptor suitable
 // for use in a grpc.Dial call.
-//
-// For example:
-//     tracer := global.Tracer("client-tracer")
-//     s := grpc.Dial(
-//         grpc.WithStreamInterceptor(grpctrace.StreamClientInterceptor(tracer)),
-//         ...,  // (existing DialOptions))
 func StreamClientInterceptor(tracer trace.Tracer) grpc.StreamClientInterceptor {
 	return func(
 		ctx context.Context,
@@ -294,12 +282,6 @@ func StreamClientInterceptor(tracer trace.Tracer) grpc.StreamClientInterceptor {
 
 // UnaryServerInterceptor returns a grpc.UnaryServerInterceptor suitable
 // for use in a grpc.NewServer call.
-//
-// For example:
-//     tracer := global.Tracer("server-tracer")
-//     s := grpc.Dial(
-//         grpc.UnaryInterceptor(grpctrace.UnaryServerInterceptor(tracer)),
-//         ...,  // (existing ServerOptions))
 func UnaryServerInterceptor(tracer trace.Tracer) grpc.UnaryServerInterceptor {
 	return func(
 		ctx context.Context,
@@ -382,12 +364,6 @@ func wrapServerStream(ctx context.Context, ss grpc.ServerStream) *serverStream {
 
 // StreamServerInterceptor returns a grpc.StreamServerInterceptor suitable
 // for use in a grpc.NewServer call.
-//
-// For example:
-//     tracer := global.Tracer("server-tracer")
-//     s := grpc.Dial(
-//         grpc.StreamInterceptor(grpctrace.StreamServerInterceptor(tracer)),
-//         ...,  // (existing ServerOptions))
 func StreamServerInterceptor(tracer trace.Tracer) grpc.StreamServerInterceptor {
 	return func(
 		srv interface{},