fix: Add HTTPStrategy WithForcedIPv4LocalHost To Fix Docker Port Map (#…

…1775)

* Add HTTPStrategy WithForcedIPv4LocalHost To Fix Docker Port Map Bug
Associated docker port mapping bugs:
moby/moby#42442
moby/moby#42375
If ipv6 is enabled in docker then these bugs affect this library. This is even if we build the docker network with ipv6 disabled since the ipv6 ports are still forwarded. This creates the potential for localhost for a container to be mapped to two different ports between ipv4 and ipv6. This is fine if you only have one container but once you have multiple containers spun up these ports can overlap where one containers ipv4 port is the same as another containers ipv6 port, at which point if you use localhost you are not guaranteed the ipv4 address and thus can end up calling into the wrong container.

* chore: rename variable

* chore: add print for the assertion

---------

Co-authored-by: Manuel de la Peña <mdelapenya@gmail.com>

wait/http.go

@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"net/url"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/docker/go-connections/nat"
@@ -27,17 +28,18 @@ type HTTPStrategy struct {
 	timeout *time.Duration
 
 	// additional properties
-	Port              nat.Port
-	Path              string
-	StatusCodeMatcher func(status int) bool
-	ResponseMatcher   func(body io.Reader) bool
-	UseTLS            bool
-	AllowInsecure     bool
-	TLSConfig         *tls.Config // TLS config for HTTPS
-	Method            string      // http method
-	Body              io.Reader   // http request body
-	PollInterval      time.Duration
-	UserInfo          *url.Userinfo
+	Port               nat.Port
+	Path               string
+	StatusCodeMatcher  func(status int) bool
+	ResponseMatcher    func(body io.Reader) bool
+	UseTLS             bool
+	AllowInsecure      bool
+	TLSConfig          *tls.Config // TLS config for HTTPS
+	Method             string      // http method
+	Body               io.Reader   // http request body
+	PollInterval       time.Duration
+	UserInfo           *url.Userinfo
+	ForceIPv4LocalHost bool
 }
 
 // NewHTTPStrategy constructs a HTTP strategy waiting on port 80 and status code 200
@@ -119,6 +121,13 @@ func (ws *HTTPStrategy) WithPollInterval(pollInterval time.Duration) *HTTPStrate
 	return ws
 }
 
+// WithForcedIPv4LocalHost forces usage of localhost to be ipv4 127.0.0.1
+// to avoid ipv6 docker bugs https://github.com/moby/moby/issues/42442 https://github.com/moby/moby/issues/42375
+func (ws *HTTPStrategy) WithForcedIPv4LocalHost() *HTTPStrategy {
+	ws.ForceIPv4LocalHost = true
+	return ws
+}
+
 // ForHTTP is a convenience method similar to Wait.java
 // https://github.com/testcontainers/testcontainers-java/blob/1d85a3834bd937f80aad3a4cec249c027f31aeb4/core/src/main/java/org/testcontainers/containers/wait/strategy/Wait.java
 func ForHTTP(path string) *HTTPStrategy {
@@ -143,6 +152,10 @@ func (ws *HTTPStrategy) WaitUntilReady(ctx context.Context, target StrategyTarge
 	if err != nil {
 		return err
 	}
+	// to avoid ipv6 docker bugs https://github.com/moby/moby/issues/42442 https://github.com/moby/moby/issues/42375
+	if ws.ForceIPv4LocalHost {
+		ipAddress = strings.Replace(ipAddress, "localhost", "127.0.0.1", 1)
+	}
 
 	var mappedPort nat.Port
 	if ws.Port == "" {

wait/http_test.go

@@ -32,7 +32,7 @@ func ExampleHTTPStrategy() {
 		WaitingFor:   wait.ForHTTP("/").WithStartupTimeout(10 * time.Second),
 	}
 
-	gogs, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
 		ContainerRequest: req,
 		Started:          true,
 	})
@@ -42,12 +42,12 @@ func ExampleHTTPStrategy() {
 	// }
 
 	defer func() {
-		if err := gogs.Terminate(ctx); err != nil {
+		if err := c.Terminate(ctx); err != nil {
 			log.Fatalf("failed to terminate container: %s", err)
 		}
 	}()
 
-	state, err := gogs.State(ctx)
+	state, err := c.State(ctx)
 	if err != nil {
 		panic(err)
 	}
@@ -67,7 +67,7 @@ func ExampleHTTPStrategy_WithPort() {
 		WaitingFor:   wait.ForHTTP("/").WithPort("80/tcp"),
 	}
 
-	gogs, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
 		ContainerRequest: req,
 		Started:          true,
 	})
@@ -77,12 +77,45 @@ func ExampleHTTPStrategy_WithPort() {
 	// }
 
 	defer func() {
-		if err := gogs.Terminate(ctx); err != nil {
+		if err := c.Terminate(ctx); err != nil {
 			log.Fatalf("failed to terminate container: %s", err)
 		}
 	}()
 
-	state, err := gogs.State(ctx)
+	state, err := c.State(ctx)
+	if err != nil {
+		panic(err)
+	}
+
+	fmt.Println(state.Running)
+
+	// Output:
+	// true
+}
+
+func ExampleHTTPStrategy_WithForcedIPv4LocalHost() {
+	ctx := context.Background()
+	req := testcontainers.ContainerRequest{
+		Image:        "nginx:latest",
+		ExposedPorts: []string{"8080/tcp", "80/tcp"},
+		WaitingFor:   wait.ForHTTP("/").WithForcedIPv4LocalHost(),
+	}
+
+	c, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+		ContainerRequest: req,
+		Started:          true,
+	})
+	if err != nil {
+		panic(err)
+	}
+
+	defer func() {
+		if err := c.Terminate(ctx); err != nil {
+			log.Fatalf("failed to terminate container: %s", err)
+		}
+	}()
+
+	state, err := c.State(ctx)
 	if err != nil {
 		panic(err)
 	}