tests/integration: Move of naming/snapshot clientv3 tests (and yaml reference)

path change in clientv3/yaml/config_test

git mv clientv3/naming/grpc_test.go         tests/integration/clientv3/grpc_test.go
git mv clientv3/snapshot/*_test.go          tests/integration/snapshot
git mv clientv3/{main_test.go,example_*.go} tests/integration/clientv3/examples/

tests/integration/clientv3/examples/example_auth_test.go

@@ -0,0 +1,113 @@
+// Copyright 2016 The etcd 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 clientv3_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"go.etcd.io/etcd/v3/clientv3"
+)
+
+func ExampleAuth() {
+	cli, err := clientv3.New(clientv3.Config{
+		Endpoints:   endpoints,
+		DialTimeout: dialTimeout,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer cli.Close()
+
+	if _, err = cli.RoleAdd(context.TODO(), "root"); err != nil {
+		log.Fatal(err)
+	}
+	if _, err = cli.UserAdd(context.TODO(), "root", "123"); err != nil {
+		log.Fatal(err)
+	}
+	if _, err = cli.UserGrantRole(context.TODO(), "root", "root"); err != nil {
+		log.Fatal(err)
+	}
+
+	if _, err = cli.RoleAdd(context.TODO(), "r"); err != nil {
+		log.Fatal(err)
+	}
+
+	if _, err = cli.RoleGrantPermission(
+		context.TODO(),
+		"r",   // role name
+		"foo", // key
+		"zoo", // range end
+		clientv3.PermissionType(clientv3.PermReadWrite),
+	); err != nil {
+		log.Fatal(err)
+	}
+	if _, err = cli.UserAdd(context.TODO(), "u", "123"); err != nil {
+		log.Fatal(err)
+	}
+	if _, err = cli.UserGrantRole(context.TODO(), "u", "r"); err != nil {
+		log.Fatal(err)
+	}
+	if _, err = cli.AuthEnable(context.TODO()); err != nil {
+		log.Fatal(err)
+	}
+
+	cliAuth, err := clientv3.New(clientv3.Config{
+		Endpoints:   endpoints,
+		DialTimeout: dialTimeout,
+		Username:    "u",
+		Password:    "123",
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer cliAuth.Close()
+
+	if _, err = cliAuth.Put(context.TODO(), "foo1", "bar"); err != nil {
+		log.Fatal(err)
+	}
+
+	_, err = cliAuth.Txn(context.TODO()).
+		If(clientv3.Compare(clientv3.Value("zoo1"), ">", "abc")).
+		Then(clientv3.OpPut("zoo1", "XYZ")).
+		Else(clientv3.OpPut("zoo1", "ABC")).
+		Commit()
+	fmt.Println(err)
+
+	// now check the permission with the root account
+	rootCli, err := clientv3.New(clientv3.Config{
+		Endpoints:   endpoints,
+		DialTimeout: dialTimeout,
+		Username:    "root",
+		Password:    "123",
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer rootCli.Close()
+
+	resp, err := rootCli.RoleGet(context.TODO(), "r")
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("user u permission: key %q, range end %q\n", resp.Perm[0].Key, resp.Perm[0].RangeEnd)
+
+	if _, err = rootCli.AuthDisable(context.TODO()); err != nil {
+		log.Fatal(err)
+	}
+	// Output: etcdserver: permission denied
+	// user u permission: key "foo", range end "zoo"
+}