clientv3/concurrency: Expose examples close to the source-code.

clientv3/concurrency/example_election_test.go

@@ -0,0 +1 @@
+../../tests/integration/clientv3/concurrency/example_election_test.go

clientv3/concurrency/example_mutex_test.go

@@ -0,0 +1 @@
+../../tests/integration/clientv3/concurrency/example_mutex_test.go

clientv3/concurrency/example_stm_test.go

@@ -0,0 +1 @@
+../../tests/integration/clientv3/concurrency/example_stm_test.go

clientv3/concurrency/main_test.go

@@ -0,0 +1,35 @@
+// Copyright 2017 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 concurrency_test
+
+import (
+	"testing"
+
+	"go.etcd.io/etcd/v3/pkg/testutil"
+)
+
+func exampleEndpoints() []string { return nil }
+
+func forUnitTestsRunInMockedContext(mocking func(), example func()) {
+	mocking()
+	// TODO: Call 'example' when mocking() provides realistic mocking of transport.
+
+	// The real testing logic of examples gets executed
+	// as part of ./tests/integration/clientv3/integration/...
+}
+
+func TestMain(m *testing.M) {
+	testutil.MustTestMainWithLeakDetection(m)
+}

tests/integration/clientv3/concurrency/election_test.go

@@ -28,7 +28,7 @@ import (
 func TestResumeElection(t *testing.T) {
 	const prefix = "/resume-election/"
 
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 	if err != nil {
 		log.Fatal(err)
 	}

tests/integration/clientv3/concurrency/example_election_test.go

@@ -25,8 +25,16 @@ import (
 	"go.etcd.io/etcd/v3/clientv3/concurrency"
 )
 
+func mockElection_Campaign() {
+	fmt.Println("completed first election with e2")
+	fmt.Println("completed second election with e1")
+}
+
 func ExampleElection_Campaign() {
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	forUnitTestsRunInMockedContext(
+		mockElection_Campaign,
+		func() {
+			cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 			if err != nil {
 				log.Fatal(err)
 			}
@@ -83,6 +91,7 @@ func ExampleElection_Campaign() {
 			fmt.Println("completed second election with", string((<-e.Observe(cctx)).Kvs[0].Value))
 
 			wg.Wait()
+		})
 
 	// Output:
 	// completed first election with e2

tests/integration/clientv3/concurrency/example_mutex_test.go

@@ -23,8 +23,18 @@ import (
 	"go.etcd.io/etcd/v3/clientv3/concurrency"
 )
 
+func mockMutex_TryLock() {
+	fmt.Println("acquired lock for s1")
+	fmt.Println("cannot acquire lock for s2, as already locked in another session")
+	fmt.Println("released lock for s1")
+	fmt.Println("acquired lock for s2")
+}
+
 func ExampleMutex_TryLock() {
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	forUnitTestsRunInMockedContext(
+		mockMutex_TryLock,
+		func() {
+			cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 			if err != nil {
 				log.Fatal(err)
 			}
@@ -66,6 +76,7 @@ func ExampleMutex_TryLock() {
 				log.Fatal(err)
 			}
 			fmt.Println("acquired lock for s2")
+		})
 
 	// Output:
 	// acquired lock for s1
@@ -74,8 +85,17 @@ func ExampleMutex_TryLock() {
 	// acquired lock for s2
 }
 
+func mockMutex_Lock() {
+	fmt.Println("acquired lock for s1")
+	fmt.Println("released lock for s1")
+	fmt.Println("acquired lock for s2")
+}
+
 func ExampleMutex_Lock() {
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	forUnitTestsRunInMockedContext(
+		mockMutex_Lock,
+		func() {
+			cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 			if err != nil {
 				log.Fatal(err)
 			}
@@ -118,6 +138,7 @@ func ExampleMutex_Lock() {
 
 			<-m2Locked
 			fmt.Println("acquired lock for s2")
+		})
 
 	// Output:
 	// acquired lock for s1

tests/integration/clientv3/concurrency/example_stm_test.go

@@ -25,10 +25,17 @@ import (
 	"go.etcd.io/etcd/v3/clientv3/concurrency"
 )
 
+func mockSTM_apply() {
+	fmt.Println("account sum is 500")
+}
+
 // ExampleSTM_apply shows how to use STM with a transactional
 // transfer between balances.
 func ExampleSTM_apply() {
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	forUnitTestsRunInMockedContext(
+		mockSTM_apply,
+		func() {
+			cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 			if err != nil {
 				log.Fatal(err)
 			}
@@ -92,6 +99,7 @@ func ExampleSTM_apply() {
 			}
 
 			fmt.Println("account sum is", sum)
+		})
 	// Output:
 	// account sum is 500
 }

tests/integration/clientv3/concurrency/main_test.go

@@ -15,30 +15,28 @@
 package concurrency_test
 
 import (
-	"fmt"
 	"os"
 	"testing"
-	"time"
 
 	"go.etcd.io/etcd/tests/v3/integration"
 	"go.etcd.io/etcd/v3/pkg/testutil"
 )
 
-var endpoints []string
+var lazyCluster = integration.NewLazyCluster()
 
-// TestMain sets up an etcd cluster for running the examples.
-func TestMain(m *testing.M) {
-	cfg := integration.ClusterConfig{Size: 1}
-	clus := integration.NewClusterV3(nil, &cfg)
-	endpoints = []string{clus.Client(0).Endpoints()[0]}
-	v := m.Run()
-	clus.Terminate(nil)
-	if err := testutil.CheckAfterTest(time.Second); err != nil {
-		fmt.Fprintf(os.Stderr, "%v", err)
-		os.Exit(1)
+func exampleEndpoints() []string { return lazyCluster.EndpointsV3() }
+
+func forUnitTestsRunInMockedContext(mocking func(), example func()) {
+	// For integration tests runs in the provided environment
+	example()
 }
-	if v == 0 && testutil.CheckLeakedGoroutine() {
-		os.Exit(1)
+
+// TestMain sets up an etcd cluster if running the examples.
+func TestMain(m *testing.M) {
+	v := m.Run()
+	lazyCluster.Terminate()
+	if v == 0 {
+		testutil.MustCheckLeakedGoroutine()
 	}
 	os.Exit(v)
 }

tests/integration/clientv3/concurrency/mutex_test.go

@@ -23,7 +23,7 @@ import (
 )
 
 func TestMutexLockSessionExpired(t *testing.T) {
-	cli, err := clientv3.New(clientv3.Config{Endpoints: endpoints})
+	cli, err := clientv3.New(clientv3.Config{Endpoints: exampleEndpoints()})
 	if err != nil {
 		t.Fatal(err)
 	}