Set DEBUG_PORT to bind explicitly with "0.0.0.0" for debug compatibility (#260)

closes #259

Signed-off-by: Niko Köbler <niko@n-k.de>

Author: dasniko

pom.xml

@@ -185,6 +185,12 @@
             <version>${shrinkwrap-resolver.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.awaitility</groupId>
+            <artifactId>awaitility</artifactId>
+            <version>4.3.0</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/dasniko/testcontainers/keycloak/ExtendableKeycloakContainer.java

@@ -258,7 +258,7 @@ protected void configure() {
 
         if (debugEnabled) {
             withEnv("DEBUG", Boolean.toString(Boolean.TRUE));
-            withEnv("DEBUG_PORT", String.valueOf(KEYCLOAK_PORT_DEBUG));
+            withEnv("DEBUG_PORT", "0.0.0.0:" + KEYCLOAK_PORT_DEBUG);
             if (debugHostPort > 0) {
                 addFixedExposedPort(debugHostPort, KEYCLOAK_PORT_DEBUG);
             } else {

src/test/java/dasniko/testcontainers/keycloak/KeycloakContainerTest.java

@@ -2,6 +2,7 @@
 
 import io.restassured.response.ValidatableResponse;
 import jakarta.ws.rs.NotAuthorizedException;
+import org.awaitility.Awaitility;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
@@ -10,9 +11,12 @@
 import org.testcontainers.containers.ContainerLaunchException;
 
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
 import java.net.Socket;
+import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.time.Instant;
 
@@ -229,13 +233,30 @@ private static int findFreePort() {
         }
     }
 
-    private void testDebugPortAvailable(final String debugHost, final int debugPort) throws IOException {
-        try (var debugSocket = new Socket()) {
-            try {
-                debugSocket.connect(new InetSocketAddress(debugHost, debugPort));
-            } catch (IOException e) {
-                fail(String.format("Debug port %d cannot be reached.", debugPort));
-            }
+    private void testDebugPortAvailable(String debugHost, int debugPort) {
+        Awaitility.await()
+            .atMost(Duration.ofSeconds(30))
+            .pollInterval(Duration.ofMillis(500))
+            .pollDelay(Duration.ofSeconds(1))
+            .untilAsserted(() -> assertJdwpHandshake(debugHost, debugPort));
+    }
+
+    private void assertJdwpHandshake(String debugHost, int debugPort) throws IOException {
+        try (Socket socket = new Socket()) {
+            socket.connect(new InetSocketAddress(debugHost, debugPort), 2000);
+            socket.setSoTimeout(2000);
+
+            // send JDWP Handshake
+            OutputStream out = socket.getOutputStream();
+            out.write("JDWP-Handshake".getBytes(StandardCharsets.US_ASCII));
+            out.flush();
+
+            InputStream in = socket.getInputStream();
+            byte[] response = new byte[14];
+            int bytesRead = in.read(response);
+
+            assertThat(bytesRead, is(14));
+            assertThat(new String(response, StandardCharsets.US_ASCII), equalTo("JDWP-Handshake"));
         }
     }
 }