Adjust test fixture lifecycle ordering in apm integration tests (elastic#136926)

Author: mark-vieira

test/external-modules/apm-integration/src/javaRestTest/java/org/elasticsearch/test/apmintegration/TracesApmIT.java

@@ -22,7 +22,8 @@
 import org.hamcrest.Matcher;
 import org.hamcrest.StringDescription;
 import org.junit.ClassRule;
-import org.junit.Rule;
+import org.junit.rules.TestRule;
+import org.junit.runners.model.Statement;
 
 import java.io.IOException;
 import java.util.Arrays;
@@ -43,20 +44,45 @@ public class TracesApmIT extends ESRestTestCase {
     final String traceIdValue = "0af7651916cd43dd8448eb211c80319c";
     final String traceParentValue = "00-" + traceIdValue + "-b7ad6b7169203331-01";
 
-    @ClassRule
     public static RecordingApmServer mockApmServer = new RecordingApmServer();
 
-    @Rule
-    public ElasticsearchCluster cluster = ElasticsearchCluster.local()
+    public static ElasticsearchCluster cluster = ElasticsearchCluster.local()
         .distribution(DistributionType.INTEG_TEST)
         .module("test-apm-integration")
         .module("apm")
         .setting("telemetry.metrics.enabled", "false")
         .setting("telemetry.tracing.enabled", "true")
         .setting("telemetry.agent.metrics_interval", "1s")
-        .setting("telemetry.agent.server_url", "http://127.0.0.1:" + mockApmServer.getPort())
+        .setting("telemetry.agent.server_url", () -> "http://127.0.0.1:" + mockApmServer.getPort())
         .build();
 
+    @ClassRule
+    // Custom test rule which manually orders test fixtures. A RuleChain won't work here due to the specific order we require, which is:
+    // 1. Start the mock APM server
+    // 2. Start ES cluster
+    // 3. Run the test
+    // 4. Stop the mock APM server
+    // 5. Stop ES cluster
+    public static TestRule rule = (base, description) -> {
+        return new Statement() {
+            @Override
+            public void evaluate() throws Throwable {
+                mockApmServer.before();
+                Statement s = new Statement() {
+                    @Override
+                    public void evaluate() throws Throwable {
+                        try {
+                            base.evaluate();
+                        } finally {
+                            mockApmServer.after();
+                        }
+                    }
+                };
+                cluster.apply(s, description).evaluate();
+            }
+        };
+    };
+
     @Override
     protected String getTestRestCluster() {
         return cluster.getHttpAddresses();