Fix fixed host port test

core/src/test/java/org/testcontainers/junit/FixedHostPortContainerTest.java

@@ -1,10 +1,19 @@
 package org.testcontainers.junit;
 
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
 import org.junit.Test;
 import org.testcontainers.containers.FixedHostPortGenericContainer;
 import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.wait.strategy.LogMessageWaitStrategy;
+import org.testcontainers.containers.wait.strategy.WaitStrategy;
 
+import java.io.BufferedReader;
 import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
 
 /**
  * Test of {@link FixedHostPortGenericContainer}. Note that this is not an example of typical use (usually, a container
@@ -14,28 +23,82 @@
  */
 public class FixedHostPortContainerTest {
 
-    private static final int REDIS_PORT = 6379;
+    /**
+     * Docker image for simple open-source HTTP echo server https://github.com/hashicorp/http-echo
+     */
+    private static final String HTTP_ECHO_IMAGE = "hashicorp/http-echo";
+
+    /**
+     * Default echo server port
+     */
+    private static final int ECHO_PORT = 5678;
+
+    /**
+     * test echo response
+     */
+    private static final String TEST_ECHO = "test-echo";
+
+    /**
+     * Waiting strategy for echo server start
+     */
+    private final WaitStrategy echoServerStartWaitStrategy = new LogMessageWaitStrategy()
+        .withRegEx(".+Server is listening.+");
 
     @Test
     public void testFixedHostPortMapping() throws IOException {
         // first find a free port on the docker host that will work for testing
-        GenericContainer portDiscoveryRedis = new GenericContainer("redis:3.0.2").withExposedPorts(REDIS_PORT);
-        portDiscoveryRedis.start();
-        Integer freePort = portDiscoveryRedis.getMappedPort(REDIS_PORT);
-        portDiscoveryRedis.stop();
-
-
-        // Set up a FixedHostPortGenericContainer as if this were a @Rule
-        FixedHostPortGenericContainer redis = new FixedHostPortGenericContainer("redis:3.0.2").withFixedExposedPort(freePort, REDIS_PORT);
-        redis.start();
-
-//        Config redisConfig = new Config();
-//        redisConfig.useSingleServer().setAddress(redis.getContainerIpAddress() + ":" + freePort);
-//        Redisson redisson = Redisson.create(redisConfig);
-//
-//        redisson.getBucket("test").set("foo");
-//
-//        assertEquals("The bucket content was successfully set", "foo", redisson.getBucket("test").get());
-//        assertEquals("The container returns the fixed port from getMappedPort(...)", freePort, redis.getMappedPort(REDIS_PORT));
+        GenericContainer echoServer = new GenericContainer(HTTP_ECHO_IMAGE)
+            .withCommand(String.format("-text=%s", TEST_ECHO))
+            .withExposedPorts(ECHO_PORT)
+            .waitingFor(this.echoServerStartWaitStrategy);
+
+        echoServer.start();
+        final Integer unusedHostPort = echoServer.getMappedPort(ECHO_PORT);
+
+        String content = this.getHttpResponse(unusedHostPort);
+
+        assertThat("Returned echo does not match expected", content, equalTo(TEST_ECHO));
+
+        echoServer.stop();
+
+        // now starting echo server container mapped to known-as-free host port
+        echoServer = new FixedHostPortGenericContainer(HTTP_ECHO_IMAGE)
+            .withFixedExposedPort(unusedHostPort, ECHO_PORT)
+            .withCommand(String.format("-text=%s", TEST_ECHO))
+            .waitingFor(this.echoServerStartWaitStrategy);
+
+        echoServer.start();
+
+        assertThat("Port mapping does not seem to match given fixed port",
+            echoServer.getMappedPort(ECHO_PORT), equalTo(unusedHostPort));
+
+        content = this.getHttpResponse(unusedHostPort);
+
+        assertThat("Returned echo from fixed port does not match expected", content, equalTo(TEST_ECHO));
+
+        echoServer.stop();
+    }
+
+    /**
+     * Simple pure-java web request/response functionality from localhost
+     *
+     * @param port to send request to
+     * @return response content
+     * @throws IOException if any
+     */
+    private String getHttpResponse(Integer port) throws IOException {
+        final URL url = new URL(String.format("http://localhost:%d", port));
+        final HttpURLConnection con = (HttpURLConnection) url.openConnection();
+        con.setRequestMethod("GET");
+        final StringBuilder response;
+        try (final BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()))) {
+            String inputLine;
+            response = new StringBuilder();
+            while ((inputLine = in.readLine()) != null) {
+                response.append(inputLine);
+            }
+        }
+        con.disconnect();
+        return response.toString();
     }
 }