go/examples/example_test.go - qpid-proton - Git at Google

 /*
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
 distributed with this work for additional information
 regarding copyright ownership.  The ASF licenses this file
 to you 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.
 */

 // Tests to verify that example code behaves as expected.
 // Run in this directory with `go test example_test.go`
 //
 package main

 import (
 	"bufio"
 	"bytes"
 	"flag"
 	"fmt"
 	"io"
 	"math/rand"
 	"net"
 	"os"
 	"os/exec"
 	"path"
 	"path/filepath"
 	"reflect"
 	"testing"
 	"time"
 )

 func fatalIf(t *testing.T, err error) {
 	if err != nil {
 		t.Fatalf("%s", err)
 	}
 }

 // A demo broker process
 type broker struct {
 	cmd    *exec.Cmd
 	addr   string
 	runerr chan error
 	err    error
 }

 // Try to connect to the broker to verify it is ready, give up after a timeout
 func (b *broker) check() error {
 	dialer := net.Dialer{Deadline: time.Now().Add(time.Second * 10)}
 	for {
 		c, err := dialer.Dial("tcp", b.addr)
 		if err == nil { // Success
 			c.Close()
 			return nil
 		}
 		select {
 		case runerr := <-b.runerr: // Broker exited.
 			return runerr
 		default:
 		}
 		if neterr, ok := err.(net.Error); ok && neterr.Timeout() { // Running but timed out
 			b.stop()
 			return fmt.Errorf("timed out waiting for broker")
 		}
 		time.Sleep(time.Second / 10)
 	}
 }

 // Start the demo broker, wait till it is listening on *addr. No-op if already started.
 func (b *broker) start(t *testing.T) error {
 	if b.cmd == nil { // Not already started
 		b.addr = fmt.Sprintf("127.0.0.1:%d", rand.Intn(10000)+10000)
 		b.cmd = exampleCommand(t, *brokerName, "-addr", b.addr)
 		b.runerr = make(chan error)
 		b.cmd.Stderr, b.cmd.Stdout = os.Stderr, os.Stdout
 		b.err = b.cmd.Start()
 		if b.err == nil {
 			go func() { b.runerr <- b.cmd.Wait() }()
 		} else {
 			b.runerr <- b.err
 		}
 		b.err = b.check()
 	}
 	return b.err
 }

 func (b *broker) stop() {
 	if b != nil && b.cmd != nil {
 		b.cmd.Process.Kill()
 		<-b.runerr
 	}
 }

 func checkEqual(want interface{}, got interface{}) error {
 	if reflect.DeepEqual(want, got) {
 		return nil
 	}
 	return fmt.Errorf("%#v != %#v", want, got)
 }

 // exampleCommand returns an exec.Cmd to run an example.
 func exampleCommand(t *testing.T, prog string, arg ...string) (cmd *exec.Cmd) {
 	args := []string{}
 	if *debug {
 		args = append(args, "-debug=true")
 	}
 	args = append(args, arg...)
 	prog, err := filepath.Abs(path.Join(*dir, prog))
 	fatalIf(t, err)
 	if _, err := os.Stat(prog); err == nil {
 		cmd = exec.Command(prog, args...)
 	} else if _, err := os.Stat(prog + ".go"); err == nil {
 		args = append([]string{"run", prog + ".go"}, args...)
 		cmd = exec.Command("go", args...)
 	} else {
 		t.Fatalf("Cannot find binary or source for %s", prog)
 	}
 	cmd.Stderr = os.Stderr
 	return cmd
 }

 // Run an example Go program, return the combined output as a string.
 func runExample(t *testing.T, prog string, arg ...string) (string, error) {
 	cmd := exampleCommand(t, prog, arg...)
 	out, err := cmd.Output()
 	return string(out), err
 }

 func prefix(prefix string, err error) error {
 	if err != nil {
 		return fmt.Errorf("%s: %s", prefix, err)
 	}
 	return nil
 }

 func runExampleWant(t *testing.T, want string, prog string, args ...string) error {
 	out, err := runExample(t, prog, args...)
 	if err != nil {
 		return fmt.Errorf("%s failed: %s: %s", prog, err, out)
 	}
 	return prefix(prog, checkEqual(want, out))
 }

 func exampleArgs(args ...string) []string {
 	for i := 0; i < *connections; i++ {
 		args = append(args, fmt.Sprintf("amqp://%s/%s%d", testBroker.addr, "q", i))
 	}
 	return args
 }

 // Send then receive
 func TestExampleSendReceive(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skip demo tests in short mode")
 	}
 	testBroker.start(t)
 	err := runExampleWant(t,
 		fmt.Sprintf("Received all %d acknowledgements\n", expected),
 		"send",
 		exampleArgs("-count", fmt.Sprintf("%d", *count))...)
 	if err != nil {
 		t.Fatal(err)
 	}
 	err = runExampleWant(t,
 		fmt.Sprintf("Listening on %v connections\nReceived %v messages\n", *connections, *count**connections),
 		"receive",
 		exampleArgs("-count", fmt.Sprintf("%d", *count**connections))...)
 	if err != nil {
 		t.Fatal(err)
 	}
 }

 var ready error

 func init() { ready = fmt.Errorf("Ready") }

 // Run receive in a goroutine.
 // Send ready on errchan when it is listening.
 // Send final error when it is done.
 // Returns the Cmd, caller must Wait()
 func goReceiveWant(t *testing.T, errchan chan<- error, want string, arg ...string) *exec.Cmd {
 	cmd := exampleCommand(t, "receive", arg...)
 	go func() {
 		pipe, err := cmd.StdoutPipe()
 		if err != nil {
 			errchan <- err
 			return
 		}
 		out := bufio.NewReader(pipe)
 		cmd.Start()
 		line, err := out.ReadString('\n')
 		if err != nil && err != io.EOF {
 			errchan <- err
 			return
 		}
 		listening := "Listening on 3 connections\n"
 		if line != listening {
 			errchan <- checkEqual(listening, line)
 			return
 		}
 		errchan <- ready
 		buf := bytes.Buffer{}
 		io.Copy(&buf, out) // Collect the rest of the output
 		cmd.Wait()
 		errchan <- checkEqual(want, buf.String())
 		close(errchan)
 	}()
 	return cmd
 }

 // Start receiver first, wait till it is running, then send.
 func TestExampleReceiveSend(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skip demo tests in short mode")
 	}
 	testBroker.start(t)

 	// Start receiver, wait for "listening" message on stdout
 	recvCmd := exampleCommand(t, "receive", exampleArgs(fmt.Sprintf("-count=%d", expected))...)
 	pipe, err := recvCmd.StdoutPipe()
 	if err != nil {
 		t.Fatal(err)
 	}
 	recvCmd.Start()
 	out := bufio.NewReader(pipe)
 	line, err := out.ReadString('\n')
 	if err := checkEqual("Listening on 3 connections\n", line); err != nil {
 		t.Fatal(err)
 	}

 	if err := runExampleWant(t,
 		fmt.Sprintf("Received all %d acknowledgements\n", expected),
 		"send",
 		exampleArgs("-count", fmt.Sprintf("%d", *count))...); err != nil {
 		t.Fatal(err)
 	}

 	buf := bytes.Buffer{}
 	io.Copy(&buf, out)
 	if err := checkEqual(fmt.Sprintf("Received %d messages\n", expected), buf.String()); err != nil {
 		t.Fatal(err)
 	}
 }

 var testBroker *broker

 var debug = flag.Bool("debug", false, "Debugging output from examples")
 var brokerName = flag.String("broker", "broker", "Name of broker executable to run")
 var count = flag.Int("count", 3, "Count of messages to send in tests")
 var connections = flag.Int("connections", 3, "Number of connections to make in tests")
 var dir = flag.String("dir", "electron", "Directory containing example sources or binaries")
 var expected int

 func TestMain(m *testing.M) {
 	expected = (*count) * (*connections)
 	rand.Seed(time.Now().UTC().UnixNano())
 	testBroker = &broker{} // Broker is started on-demand by tests.
 	status := m.Run()
 	testBroker.stop()
 	os.Exit(status)
 }
	/*
	Licensed to the Apache Software Foundation (ASF) under one
	or more contributor license agreements. See the NOTICE file
	distributed with this work for additional information
	regarding copyright ownership. The ASF licenses this file
	to you 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.
	*/

	// Tests to verify that example code behaves as expected.
	// Run in this directory with `go test example_test.go`
	//
	package main

	import (
	"bufio"
	"bytes"
	"flag"
	"fmt"
	"io"
	"math/rand"
	"net"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"reflect"
	"testing"
	"time"
	)

	func fatalIf(t *testing.T, err error) {
	if err != nil {
	t.Fatalf("%s", err)
	}
	}

	// A demo broker process
	type broker struct {
	cmd *exec.Cmd
	addr string
	runerr chan error
	err error
	}

	// Try to connect to the broker to verify it is ready, give up after a timeout
	func (b *broker) check() error {
	dialer := net.Dialer{Deadline: time.Now().Add(time.Second * 10)}
	for {
	c, err := dialer.Dial("tcp", b.addr)
	if err == nil { // Success
	c.Close()
	return nil
	}
	select {
	case runerr := <-b.runerr: // Broker exited.
	return runerr
	default:
	}
	if neterr, ok := err.(net.Error); ok && neterr.Timeout() { // Running but timed out
	b.stop()
	return fmt.Errorf("timed out waiting for broker")
	}
	time.Sleep(time.Second / 10)
	}
	}

	// Start the demo broker, wait till it is listening on *addr. No-op if already started.
	func (b broker) start(t testing.T) error {
	if b.cmd == nil { // Not already started
	b.addr = fmt.Sprintf("127.0.0.1:%d", rand.Intn(10000)+10000)
	b.cmd = exampleCommand(t, *brokerName, "-addr", b.addr)
	b.runerr = make(chan error)
	b.cmd.Stderr, b.cmd.Stdout = os.Stderr, os.Stdout
	b.err = b.cmd.Start()
	if b.err == nil {
	go func() { b.runerr <- b.cmd.Wait() }()
	} else {
	b.runerr <- b.err
	}
	b.err = b.check()
	}
	return b.err
	}

	func (b *broker) stop() {
	if b != nil && b.cmd != nil {
	b.cmd.Process.Kill()
	<-b.runerr
	}
	}

	func checkEqual(want interface{}, got interface{}) error {
	if reflect.DeepEqual(want, got) {
	return nil
	}
	return fmt.Errorf("%#v != %#v", want, got)
	}

	// exampleCommand returns an exec.Cmd to run an example.
	func exampleCommand(t testing.T, prog string, arg ...string) (cmd exec.Cmd) {
	args := []string{}
	if *debug {
	args = append(args, "-debug=true")
	}
	args = append(args, arg...)
	prog, err := filepath.Abs(path.Join(*dir, prog))
	fatalIf(t, err)
	if _, err := os.Stat(prog); err == nil {
	cmd = exec.Command(prog, args...)
	} else if _, err := os.Stat(prog + ".go"); err == nil {
	args = append([]string{"run", prog + ".go"}, args...)
	cmd = exec.Command("go", args...)
	} else {
	t.Fatalf("Cannot find binary or source for %s", prog)
	}
	cmd.Stderr = os.Stderr
	return cmd
	}

	// Run an example Go program, return the combined output as a string.
	func runExample(t *testing.T, prog string, arg ...string) (string, error) {
	cmd := exampleCommand(t, prog, arg...)
	out, err := cmd.Output()
	return string(out), err
	}

	func prefix(prefix string, err error) error {
	if err != nil {
	return fmt.Errorf("%s: %s", prefix, err)
	}
	return nil
	}

	func runExampleWant(t *testing.T, want string, prog string, args ...string) error {
	out, err := runExample(t, prog, args...)
	if err != nil {
	return fmt.Errorf("%s failed: %s: %s", prog, err, out)
	}
	return prefix(prog, checkEqual(want, out))
	}

	func exampleArgs(args ...string) []string {
	for i := 0; i < *connections; i++ {
	args = append(args, fmt.Sprintf("amqp://%s/%s%d", testBroker.addr, "q", i))
	}
	return args
	}

	// Send then receive
	func TestExampleSendReceive(t *testing.T) {
	if testing.Short() {
	t.Skip("Skip demo tests in short mode")
	}
	testBroker.start(t)
	err := runExampleWant(t,
	fmt.Sprintf("Received all %d acknowledgements\n", expected),
	"send",
	exampleArgs("-count", fmt.Sprintf("%d", *count))...)
	if err != nil {
	t.Fatal(err)
	}
	err = runExampleWant(t,
	fmt.Sprintf("Listening on %v connections\nReceived %v messages\n", connections, count**connections),
	"receive",
	exampleArgs("-count", fmt.Sprintf("%d", count*connections))...)
	if err != nil {
	t.Fatal(err)
	}
	}

	var ready error

	func init() { ready = fmt.Errorf("Ready") }

	// Run receive in a goroutine.
	// Send ready on errchan when it is listening.
	// Send final error when it is done.
	// Returns the Cmd, caller must Wait()
	func goReceiveWant(t testing.T, errchan chan<- error, want string, arg ...string) exec.Cmd {
	cmd := exampleCommand(t, "receive", arg...)
	go func() {
	pipe, err := cmd.StdoutPipe()
	if err != nil {
	errchan <- err
	return
	}
	out := bufio.NewReader(pipe)
	cmd.Start()
	line, err := out.ReadString('\n')
	if err != nil && err != io.EOF {
	errchan <- err
	return
	}
	listening := "Listening on 3 connections\n"
	if line != listening {
	errchan <- checkEqual(listening, line)
	return
	}
	errchan <- ready
	buf := bytes.Buffer{}
	io.Copy(&buf, out) // Collect the rest of the output
	cmd.Wait()
	errchan <- checkEqual(want, buf.String())
	close(errchan)
	}()
	return cmd
	}

	// Start receiver first, wait till it is running, then send.
	func TestExampleReceiveSend(t *testing.T) {
	if testing.Short() {
	t.Skip("Skip demo tests in short mode")
	}
	testBroker.start(t)

	// Start receiver, wait for "listening" message on stdout
	recvCmd := exampleCommand(t, "receive", exampleArgs(fmt.Sprintf("-count=%d", expected))...)
	pipe, err := recvCmd.StdoutPipe()
	if err != nil {
	t.Fatal(err)
	}
	recvCmd.Start()
	out := bufio.NewReader(pipe)
	line, err := out.ReadString('\n')
	if err := checkEqual("Listening on 3 connections\n", line); err != nil {
	t.Fatal(err)
	}

	if err := runExampleWant(t,
	fmt.Sprintf("Received all %d acknowledgements\n", expected),
	"send",
	exampleArgs("-count", fmt.Sprintf("%d", *count))...); err != nil {
	t.Fatal(err)
	}

	buf := bytes.Buffer{}
	io.Copy(&buf, out)
	if err := checkEqual(fmt.Sprintf("Received %d messages\n", expected), buf.String()); err != nil {
	t.Fatal(err)
	}
	}

	var testBroker *broker

	var debug = flag.Bool("debug", false, "Debugging output from examples")
	var brokerName = flag.String("broker", "broker", "Name of broker executable to run")
	var count = flag.Int("count", 3, "Count of messages to send in tests")
	var connections = flag.Int("connections", 3, "Number of connections to make in tests")
	var dir = flag.String("dir", "electron", "Directory containing example sources or binaries")
	var expected int

	func TestMain(m *testing.M) {
	expected = (count) (*connections)
	rand.Seed(time.Now().UTC().UnixNano())
	testBroker = &broker{} // Broker is started on-demand by tests.
	status := m.Run()
	testBroker.stop()
	os.Exit(status)
	}