From 2de6229a25dfbeb15c6a8e3a961f05d7380fd334 Mon Sep 17 00:00:00 2001
From: Tobias Metzke-Bernstein <tobias.metzke@camunda.com>
Date: Fri, 9 Jun 2023 11:49:53 +0200
Subject: [PATCH] chore(webapps): retry test server start when port bound
 (#3398)

* Retries a failed test server start in case the port is still bound.
  The start will be retried 3 times at maximum. There will be a backoff
  of half a second between retries.

related to https://github.com/camunda/camunda-bpm-platform/issues/2598
---
 .../bpm/webapp/impl/util/HeaderRule.java      | 29 ++++++++++++++-----
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/webapps/assembly/src/test/java/org/camunda/bpm/webapp/impl/util/HeaderRule.java b/webapps/assembly/src/test/java/org/camunda/bpm/webapp/impl/util/HeaderRule.java
index 922e71a792a..dae92c726db 100644
--- a/webapps/assembly/src/test/java/org/camunda/bpm/webapp/impl/util/HeaderRule.java
+++ b/webapps/assembly/src/test/java/org/camunda/bpm/webapp/impl/util/HeaderRule.java
@@ -16,14 +16,14 @@
  */
 package org.camunda.bpm.webapp.impl.util;
 
-import org.eclipse.jetty.server.Server;
-import org.eclipse.jetty.webapp.WebAppContext;
-import org.junit.rules.ExternalResource;
-
 import java.io.IOException;
+import java.net.BindException;
 import java.net.HttpURLConnection;
 import java.net.ProtocolException;
 import java.net.URL;
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.webapp.WebAppContext;
+import org.junit.rules.ExternalResource;
 
 /**
  * @author Tassilo Weidner
@@ -31,11 +31,13 @@
 public class HeaderRule extends ExternalResource {
 
   protected static final int SERVER_PORT = 8085;
+  protected static final int RETRIES = 3;
 
   protected Server server = new Server(SERVER_PORT);
   protected WebAppContext webAppContext = new WebAppContext();
   protected HttpURLConnection connection = null;
 
+  @Override
   protected void before() {
     try {
       server.stop();
@@ -44,6 +46,7 @@ protected void before() {
     }
   }
 
+  @Override
   protected void after() {
     try {
       server.stop();
@@ -57,6 +60,10 @@ public void startServer(String webDescriptor, String scope) {
   }
 
   public void startServer(String webDescriptor, String scope, String contextPath) {
+    startServer(webDescriptor, scope, contextPath, RETRIES);
+  }
+
+  protected void startServer(String webDescriptor, String scope, String contextPath, int startUpRetries) {
     webAppContext.setContextPath(contextPath);
     webAppContext.setResourceBase("/");
     webAppContext.setDescriptor("src/test/resources/WEB-INF/" + scope + "/" + webDescriptor);
@@ -66,7 +73,15 @@ public void startServer(String webDescriptor, String scope, String contextPath)
     try {
       server.start();
     } catch (Exception e) {
-      throw new RuntimeException(e);
+      if (e.getCause() instanceof BindException && startUpRetries > 0) {
+        try {
+          Thread.sleep(500L);
+        } catch (Exception ex) {
+        }
+        startServer(webDescriptor, scope, contextPath, --startUpRetries);
+      } else {
+        throw new RuntimeException(e);
+      }
     }
   }
 
@@ -147,11 +162,11 @@ public int getResponseCode() {
       throw new RuntimeException(e);
     }
   }
-  
+
   public String getSessionCookieRegex(String path, String sameSite, boolean secure) {
     return getSessionCookieRegex(path, "JSESSIONID", sameSite, secure);
   }
-  
+
   public String getSessionCookieRegex(String path, String cookieName, String sameSite, boolean secure) {
     StringBuilder regex = new StringBuilder(cookieName + "=.*;\\W*Path=/");
     if (path != null) {