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How to use newCapturingPassThroughWriter method of testcontainers Package

Best Testcontainers-go code snippet using testcontainers.newCapturingPassThroughWriter

compose.go

Source:compose.go

...226		cmd.Env = append(cmd.Env, key+"="+value)227	}228	stdoutIn, _ := cmd.StdoutPipe()229	stderrIn, _ := cmd.StderrPipe()230	stdout := newCapturingPassThroughWriter(os.Stdout)231	stderr := newCapturingPassThroughWriter(os.Stderr)232	err := cmd.Start()233	if err != nil {234		execCmd := []string{"Starting command", dirContext, binary}235		execCmd = append(execCmd, args...)236		return ExecError{237			// add information about the CMD and arguments used238			Command:      execCmd,239			StdoutOutput: stdout.Bytes(),240			StderrOutput: stderr.Bytes(),241			Error:        err,242			Stderr:       errStderr,243			Stdout:       errStdout,244		}245	}246	var wg sync.WaitGroup247	wg.Add(1)248	go func() {249		_, errStdout = io.Copy(stdout, stdoutIn)250		wg.Done()251	}()252	_, errStderr = io.Copy(stderr, stderrIn)253	wg.Wait()254	err = cmd.Wait()255	execCmd := []string{"Reading std", dirContext, binary}256	execCmd = append(execCmd, args...)257	return ExecError{258		Command:      execCmd,259		StdoutOutput: stdout.Bytes(),260		StderrOutput: stderr.Bytes(),261		Error:        err,262		Stderr:       errStderr,263		Stdout:       errStdout,264	}265}266func executeCompose(dc *LocalDockerCompose, args []string) ExecError {267	if which(dc.Executable) != nil {268		return ExecError{269			Command: []string{dc.Executable},270			Error:   fmt.Errorf("Local Docker Compose not found. Is %s on the PATH?", dc.Executable),271		}272	}273	environment := dc.getDockerComposeEnvironment()274	for k, v := range dc.Env {275		environment[k] = v276	}277	cmds := []string{}278	pwd := "."279	if len(dc.absComposeFilePaths) > 0 {280		pwd, _ = filepath.Split(dc.absComposeFilePaths[0])281		for _, abs := range dc.absComposeFilePaths {282			cmds = append(cmds, "-f", abs)283		}284	} else {285		cmds = append(cmds, "-f", "docker-compose.yml")286	}287	cmds = append(cmds, args...)288	execErr := execute(pwd, environment, dc.Executable, cmds)289	err := execErr.Error290	if err != nil {291		args := strings.Join(dc.Cmd, " ")292		return ExecError{293			Command: []string{dc.Executable},294			Error:   fmt.Errorf("Local Docker compose exited abnormally whilst running %s: [%v]. %s", dc.Executable, args, err.Error()),295		}296	}297	if dc.waitStrategySupplied {298		// If the wait strategy has been executed once for all services during startup , disable it so that it is not invoked while tearing down299		dc.waitStrategySupplied = false300		if err := dc.applyStrategyToRunningContainer(); err != nil {301			return ExecError{302				Error: fmt.Errorf("one or more wait strategies could not be applied to the running containers: %w", err),303			}304		}305	}306	return execErr307}308// capturingPassThroughWriter is a writer that remembers309// data written to it and passes it to w310type capturingPassThroughWriter struct {311	buf bytes.Buffer312	w   io.Writer313}314// newCapturingPassThroughWriter creates new capturingPassThroughWriter315func newCapturingPassThroughWriter(w io.Writer) *capturingPassThroughWriter {316	return &capturingPassThroughWriter{317		w: w,318	}319}320func (w *capturingPassThroughWriter) Write(d []byte) (int, error) {321	w.buf.Write(d)322	return w.w.Write(d)323}324// Bytes returns bytes written to the writer325func (w *capturingPassThroughWriter) Bytes() []byte {326	b := w.buf.Bytes()327	if b == nil {328		b = []byte{}329	}...

compose_local.go

Source:compose_local.go

...220		cmd.Env = append(cmd.Env, key+"="+value)221	}222	stdoutIn, _ := cmd.StdoutPipe()223	stderrIn, _ := cmd.StderrPipe()224	stdout := newCapturingPassThroughWriter(os.Stdout)225	stderr := newCapturingPassThroughWriter(os.Stderr)226	err := cmd.Start()227	if err != nil {228		execCmd := []string{"Starting command", dirContext, binary}229		execCmd = append(execCmd, args...)230		return ExecError{231			// add information about the CMD and arguments used232			Command:      execCmd,233			StdoutOutput: stdout.Bytes(),234			StderrOutput: stderr.Bytes(),235			Error:        err,236			Stderr:       errStderr,237			Stdout:       errStdout,238		}239	}240	var wg sync.WaitGroup241	wg.Add(1)242	go func() {243		_, errStdout = io.Copy(stdout, stdoutIn)244		wg.Done()245	}()246	_, errStderr = io.Copy(stderr, stderrIn)247	wg.Wait()248	err = cmd.Wait()249	execCmd := []string{"Reading std", dirContext, binary}250	execCmd = append(execCmd, args...)251	return ExecError{252		Command:      execCmd,253		StdoutOutput: stdout.Bytes(),254		StderrOutput: stderr.Bytes(),255		Error:        err,256		Stderr:       errStderr,257		Stdout:       errStdout,258	}259}260func executeCompose(dc *LocalDockerCompose, args []string) ExecError {261	if which(dc.Executable) != nil {262		return ExecError{263			Command: []string{dc.Executable},264			Error:   fmt.Errorf("Local Docker Compose not found. Is %s on the PATH?", dc.Executable),265		}266	}267	environment := dc.getDockerComposeEnvironment()268	for k, v := range dc.Env {269		environment[k] = v270	}271	var cmds []string272	pwd := "."273	if len(dc.absComposeFilePaths) > 0 {274		pwd, _ = filepath.Split(dc.absComposeFilePaths[0])275		for _, abs := range dc.absComposeFilePaths {276			cmds = append(cmds, "-f", abs)277		}278	} else {279		cmds = append(cmds, "-f", "docker-compose.yml")280	}281	cmds = append(cmds, args...)282	execErr := execute(pwd, environment, dc.Executable, cmds)283	err := execErr.Error284	if err != nil {285		args := strings.Join(dc.Cmd, " ")286		return ExecError{287			Command: []string{dc.Executable},288			Error:   fmt.Errorf("Local Docker compose exited abnormally whilst running %s: [%v]. %s", dc.Executable, args, err.Error()),289		}290	}291	if dc.waitStrategySupplied {292		// If the wait strategy has been executed once for all services during startup , disable it so that it is not invoked while tearing down293		dc.waitStrategySupplied = false294		if err := dc.applyStrategyToRunningContainer(); err != nil {295			return ExecError{296				Error: fmt.Errorf("one or more wait strategies could not be applied to the running containers: %w", err),297			}298		}299	}300	return execErr301}302// capturingPassThroughWriter is a writer that remembers303// data written to it and passes it to w304type capturingPassThroughWriter struct {305	buf bytes.Buffer306	w   io.Writer307}308// newCapturingPassThroughWriter creates new capturingPassThroughWriter309func newCapturingPassThroughWriter(w io.Writer) *capturingPassThroughWriter {310	return &capturingPassThroughWriter{311		w: w,312	}313}314func (w *capturingPassThroughWriter) Write(d []byte) (int, error) {315	w.buf.Write(d)316	return w.w.Write(d)317}318// Bytes returns bytes written to the writer319func (w *capturingPassThroughWriter) Bytes() []byte {320	b := w.buf.Bytes()321	if b == nil {322		b = []byte{}323	}...

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		ExposedPorts: []string{"3000/tcp"},6		WaitingFor:   wait.ForListeningPort("3000/tcp"),7	}8	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{9	})10	if err != nil {11		log.Fatal(err)12	}13	ip, err := c.Host(ctx)14	if err != nil {15		log.Fatal(err)16	}17	port, err := c.MappedPort(ctx, "3000")18	if err != nil {19		log.Fatal(err)20	}21	logs, err := c.Logs(ctx)22	if err != nil {23		log.Fatal(err)24	}25	logs, err := c.Logs(ctx)26	if err != nil {27		log.Fatal(err)28	}29	defer c.Terminate(ctx)30	file, err := os.Create("output.txt")31	if err != nil {32		log.Fatal(err)33	}34	defer file.Close()35	_, err = file.WriteString(logs)36	if err != nil {37		log.Fatal(err)38	}39	fmt.Printf("Container IP: %s\n", ip)40	fmt.Printf("Container port: %s\n", port.Port())41}42import (43func main() {44	ctx := context.Background()45	req := testcontainers.ContainerRequest{46		ExposedPorts: []string{"3000/tcp"},47		WaitingFor:   wait.ForListeningPort("3000/tcp"),48	}49	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		ExposedPorts: []string{"5432/tcp"},6		WaitingFor:   wait.ForLog("database system is ready to accept connections"),7	}8	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{9	})10	if err != nil {11		log.Fatal(err)12	}13	defer container.Terminate(ctx)14	port, err := container.MappedPort(ctx, "5432")15	if err != nil {16		log.Fatal(err)17	}18	fmt.Println(port.Int())19}20import (21func main() {22	ctx := context.Background()23	req := testcontainers.ContainerRequest{24		ExposedPorts: []string{"5432/tcp"},25		WaitingFor:   wait.ForLog("database system is ready to accept connections"),26	}27	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{28	})29	if err != nil {30		log.Fatal(err)31	}32	defer container.Terminate(ctx)33	port, err := container.MappedPort(ctx, "5432")34	if err != nil {35		log.Fatal(err)36	}37	fmt.Println(port.Int())38}39import (40func main() {41	ctx := context.Background()42	req := testcontainers.ContainerRequest{43		ExposedPorts: []string{"5432/tcp"},

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		Cmd:          []string{"sh", "-c", "while true; do echo hello; sleep 1; done"},6		ExposedPorts: []string{"80/tcp"},7		WaitingFor:   wait.ForLog("hello"),8	}9	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{10	})11	if err != nil {12		log.Fatal(err)13	}14	containerID, err := container.ContainerID(ctx)15	if err != nil {16		log.Fatal(err)17	}18	fmt.Println("Container ID: ", containerID)19	ip, err := container.Host(ctx)20	if err != nil {21		log.Fatal(err)22	}23	fmt.Println("Container IP: ", ip)24	port, err := container.MappedPort(ctx, "80")25	if err != nil {26		log.Fatal(err)27	}28	fmt.Println("Container Port: ", port.Int())29	logs, err := container.Logs(ctx)30	if err != nil {31		log.Fatal(err)32	}33	defer logs.Close()34	writer := newCapturingPassThroughWriter(os.Stdout)35	_, err = io.Copy(writer, logs)36	if err != nil {37		log.Fatal(err)38	}39	fmt.Println("Captured logs:", writer.String())40	err = container.Terminate(ctx)41	if err != nil {42		log.Fatal(err)43	}44}45type capturingPassThroughWriter struct {46}47func newCapturingPassThroughWriter(w io.Writer) *capturingPassThroughWriter {48	return &capturingPassThroughWriter{49		Writer: bufio.NewWriter(w),50		Builder: &strings.Builder{},51	}52}53func (c *capturingPassThroughWriter) Write(p []byte

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		ExposedPorts: []string{"80/tcp"},6		WaitingFor:   wait.ForHTTP("/"),7	}8	nginxContainer, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{9	})10	if err != nil {11		log.Fatal(err)12	}13	defer nginxContainer.Terminate(ctx)14	ip, err := nginxContainer.Host(ctx)15	if err != nil {16		log.Fatal(err)17	}18	port, err := nginxContainer.MappedPort(ctx, "80")19	if err != nil {20		log.Fatal(err)21	}22	if err != nil {23		log.Fatal(err)24	}25	defer resp.Body.Close()26	body, err := ioutil.ReadAll(resp.Body)27	if err != nil {28		log.Fatal(err)29	}30	fmt.Println(string(body))31}32    body {33        width: 35em;34        margin: 0 auto;35        font-family: Tahoma, Verdana, Arial, sans-serif;36    }37The main() method of the above program creates a GenericContainerRequest object and passes it to the GenericContainer() method of the testcontainers class. It then starts the container and terminates it after the main() method completes its execution. The Host() and MappedPort() methods are used to get the IP address and port of the Nginx container. Finally, the HTTP Get method is used to get

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		Cmd:          []string{"sh", "-c", "echo 'Hello world' && sleep 1s"},6		WaitingFor:   wait.ForLog("Hello world"),7		ExposedPorts: []string{"80/tcp"},8	}9	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{10	})11	if err != nil {12		log.Fatal(err)13	}14	defer c.Terminate(ctx)15	out, err := c.Exec(ctx, []string{"sh", "-c", "echo $HOSTNAME"})16	if err != nil {17		log.Fatal(err)18	}19	fmt.Println(out)20	time.Sleep(3 * time.Second)21}22import (23func main() {24	ctx := context.Background()25	req := testcontainers.ContainerRequest{26		Cmd:          []string{"sh", "-c", "echo 'Hello world' && sleep 1s"},27		WaitingFor:   wait.ForLog("Hello world"),28		ExposedPorts: []string{"80/tcp"},29	}30	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{31	})32	if err != nil {33		log.Fatal(err)34	}35	defer c.Terminate(ctx)36	out, err := c.Exec(ctx, []string{"sh", "-c", "echo $HOSTNAME"})37	if err != nil {38		log.Fatal(err)39	}40	fmt.Println(out)41	time.Sleep(3 * time.Second)42}43import (

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		Cmd:          []string{"echo", "hello world"},6		WaitingFor:   wait.ForLog("hello world"),7		ExposedPorts: []string{"80/tcp"},8		BindMounts:   map[string]string{"path/to/host/dir": "/path/to/container/dir"},9		PortBindings: map[string][]string{"80/tcp": {"8080"}},10	}11	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{12	})13	if err != nil {14		log.Fatal(err)15	}16	defer c.Terminate(ctx)17	ip, err := c.Host(ctx)18	if err != nil {19		log.Fatal(err)20	}21	port, err := c.MappedPort(ctx, "80")22	if err != nil {23		log.Fatal(err)24	}25	out, err := exec.Command("curl", ip+":"+port.Port()).Output()26	if err != nil {27		log.Fatal(err)28	}29	fmt.Println(string(out))30}31import (32func main() {33	ctx := context.Background()34	req := testcontainers.ContainerRequest{35		Cmd:          []string{"echo", "hello world"},36		WaitingFor:   wait.ForLog("hello world"),37		ExposedPorts: []string{"80/tcp"},38		BindMounts:   map[string]string{"path/to/host/dir": "/path/to/container/dir"},39		PortBindings: map[string][]string{"80/tcp": {"8080"}},40	}41	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{

newCapturingPassThroughWriter

Using AI Code Generation

1func TestNewCapturingPassThroughWriter(t *testing.T) {2    ctx := context.Background()3    req := testcontainers.GenericContainerRequest{4        ContainerRequest: testcontainers.ContainerRequest{5            Cmd:          []string{"sh", "-c", "echo hello; echo world"},6            WaitingFor:   wait.ForLog("hello"),7        },8    }9    resp, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{10    })11    require.NoError(t, err)12    defer resp.Terminate(ctx)13    out := new(bytes.Buffer)14    resp.CapturedOutput(out, "hello")15    assert.Equal(t, "hello\n", out.String())16}17func TestNewCapturingPassThroughWriter(t *testing.T) {18    ctx := context.Background()19    req := testcontainers.GenericContainerRequest{20        ContainerRequest: testcontainers.ContainerRequest{21            Cmd:          []string{"sh", "-c", "echo hello; echo world"},22            WaitingFor:   wait.ForLog("hello"),23        },24    }25    resp, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{26    })27    require.NoError(t, err)28    defer resp.Terminate(ctx)29    out := new(bytes.Buffer)30    resp.CapturedOutput(out, "hello")31    assert.Equal(t, "hello\n", out.String())32}33func TestNewCapturingPassThroughWriter(t *testing.T) {34    ctx := context.Background()35    req := testcontainers.GenericContainerRequest{36        ContainerRequest: testcontainers.ContainerRequest{37            Cmd:          []string{"sh", "-c", "echo hello; echo world"},38            WaitingFor:   wait.ForLog("hello"),39        },40    }41    resp, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	ctx := context.Background()4	req := testcontainers.ContainerRequest{5		ExposedPorts: []string{"9200/tcp", "9300/tcp"},6		WaitingFor:   wait.ForLog("started"),7	}8	elastic, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{9	})10	if err != nil {11		log.Fatalf("Could not start container: %v", err)12	}13	defer elastic.Terminate(ctx)14	ip, err := elastic.Host(ctx)15	if err != nil {16		log.Fatalf("Could not get container IP: %v", err)17	}18	if err != nil {19		log.Fatalf("Could not connect to container: %v", err)20	}21	defer resp.Body.Close()22	if _, err := io.Copy(os.Stdout, resp.Body); err != nil {23		log.Fatalf("Could not copy response body: %v", err)24	}25}26import (27func main() {28	ctx := context.Background()29	req := testcontainers.ContainerRequest{30		ExposedPorts: []string{"9200/tcp", "9300/tcp"},31		WaitingFor:   wait.ForLog("started"),32	}33	elastic, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{34	})35	if err != nil {36		log.Fatalf("Could not start container: %v",

newCapturingPassThroughWriter

Using AI Code Generation

1func main() {2	ctx := context.Background()3	req := testcontainers.ContainerRequest{4		Cmd:          []string{"echo", "hello world"},5	}6	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{7	})8	if err != nil {9		panic(err)10	}11	defer container.Terminate(ctx)12	out, err := containerLogs(ctx, container)13	if err != nil {14		panic(err)15	}16	fmt.Println(out)17}18func main() {19	ctx := context.Background()20	req := testcontainers.ContainerRequest{21		Cmd:          []string{"echo", "hello world"},22	}23	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{24	})25	if err != nil {26		panic(err)27	}28	defer container.Terminate(ctx)29	out, err := containerLogs(ctx, container)30	if err != nil {31		panic(err)32	}33	fmt.Println(out)34}35func main() {36	ctx := context.Background()37	req := testcontainers.ContainerRequest{38		Cmd:          []string{"echo", "hello world"},39	}40	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{41	})42	if err != nil {43		panic(err)44	}45	defer container.Terminate(ctx)

newCapturingPassThroughWriter

Using AI Code Generation

1import (2func main() {3	cptw := testcontainers.NewCapturingPassThroughWriter(os.Stdout)4	_, err := testcontainers.GenericContainer(5		testcontainers.GenericContainerRequest{6			ContainerRequest: testcontainers.ContainerRequest{7				Cmd:          []string{"echo", "Hello World!"},8				ExposedPorts: []string{"80/tcp"},9				WaitingFor:   testcontainers.WaitingForLog("Hello World!"),10			},11		},12	).WithLogConsumer(cptw).Start(context.Background())13	if err != nil {14		log.Fatal(err)15	}16}17import (18func main() {19	cptw := testcontainers.NewCapturingPassThroughWriter(os.Stdout)20	_, err := testcontainers.GenericContainer(21		testcontainers.GenericContainerRequest{22			ContainerRequest: testcontainers.ContainerRequest{23				Cmd:          []string{"echo", "Hello World!"},24				ExposedPorts: []string{"80/tcp"},25				WaitingFor:   testcontainers.WaitingForLog("Hello World!"),26			},27		},28	).WithLogConsumer(cptw).Start(context.Background())29	if err != nil {30		log.Fatal(err)31	}32}

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