feat(regex): add feature to wait for a regex pattern in docker contai…

src/main/java/com/github/junit5docker/DockerExtension.java

@@ -13,6 +13,7 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
+import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
 import static java.util.concurrent.CompletableFuture.supplyAsync;
@@ -56,7 +57,7 @@ private void waitForLogAccordingTo(WaitFor waitFor) {
         String expectedLog = waitFor.value();
         if (!WaitFor.NOTHING.equals(expectedLog)) {
             ExecutorService executor = Executors.newSingleThreadExecutor();
-            CompletableFuture<Boolean> logFound = supplyAsync(findFirstLogContaining(expectedLog), executor);
+            CompletableFuture<Boolean> logFound = supplyAsync(findFirstLogContaining(waitFor), executor);
             executor.shutdown();
             try {
                 boolean termination = executor.awaitTermination(waitFor.timeoutInMillis(), TimeUnit.MILLISECONDS);
@@ -72,10 +73,16 @@ private void waitForLogAccordingTo(WaitFor waitFor) {
         }
     }
 
-    private Supplier<Boolean> findFirstLogContaining(String logToFind) {
+    private Supplier<Boolean> findFirstLogContaining(WaitFor logToFind) {
         return () -> {
             try (Stream<String> logs = dockerClient.logs(containerId)) {
-                return logs.anyMatch(log -> log.contains(logToFind));
+                if (WaitFor.Engine.PLAIN_TEXT.equals(logToFind.engine())) {
+                    return logs.anyMatch(log -> log.contains(logToFind.value()));
+                }else{
+                    // Regex
+                    Pattern pattern = Pattern.compile(logToFind.value());
+                    return logs.anyMatch(log -> pattern.matcher(log).find());
+                }
             }
         };
     }

src/main/java/com/github/junit5docker/WaitFor.java

@@ -24,8 +24,24 @@
      */
     String value();
 
+    /**
+     * @return engine use to parse log
+     */
+    Engine engine() default Engine.PLAIN_TEXT ;
+
     /**
      * @return the time in milliseconds to wait for the log before giving up.
      */
     int timeoutInMillis() default DEFAULT_TIMEOUT;
+
+    enum Engine {
+        /**
+         * search for simple string
+         */
+        PLAIN_TEXT,
+        /**
+         * search for regex pattern
+         */
+        REGEX
+    }
 }

src/test/java/com/github/junit5docker/WaitForLogRegexIT.java

@@ -0,0 +1,45 @@
+package com.github.junit5docker;
+
+import org.apache.http.client.methods.CloseableHttpResponse;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+
+import static com.github.junit5docker.WaitFor.Engine.REGEX;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+
+@Docker(image = "faustxvi/open-port-later", ports = @Port(exposed = 8801, inner = 8080),
+        environments = @Environment(key = "WAITING_TIME", value = "1s"),
+        waitFor = @WaitFor(value="[a-z]{7}",engine = REGEX))
+public class WaitForLogRegexIT {
+
+    @BeforeEach
+    void verifyContainerIsReady() {
+        checkConnectionToContainer();
+    }
+
+    @Test
+    void verifyFirstContainerIsStarted() {
+        checkConnectionToContainer();
+    }
+
+    @AfterEach
+    void verifyContainerIsStillAlive() {
+        checkConnectionToContainer();
+    }
+
+    private void checkConnectionToContainer() {
+        try (CloseableHttpResponse container = HttpClientBuilder.create().build()
+                .execute(new HttpGet("http://localhost:8801"))) {
+            assertThat(container).isNotNull();
+        } catch (IOException e) {
+            fail("The port 8801 should be listening");
+        }
+    }
+}