Play instrumentation cleanup

Simplify error collecting. Use slf4j to log. randomOpenPort util.

dd-java-agent/instrumentation/play/src/main/java/datadog/trace/instrumentation/play/PlayInstrumentation.java

@@ -17,8 +17,6 @@ import io.opentracing.propagation.Format;
 import io.opentracing.propagation.TextMap;
 import io.opentracing.tag.Tags;
 import io.opentracing.util.GlobalTracer;
-import java.io.PrintWriter;
-import java.io.StringWriter;
 import java.util.*;
 import lombok.extern.slf4j.Slf4j;
 import net.bytebuddy.agent.builder.AgentBuilder;
@@ -175,26 +173,12 @@ public final class PlayInstrumentation extends Instrumenter.Configurable {
 
     public static void onError(final Span span, final Throwable t) {
       Tags.ERROR.set(span, Boolean.TRUE);
-      span.log(logsForException(t));
+      span.log(Collections.singletonMap("error.object", t));
       Tags.HTTP_STATUS.set(span, 500);
     }
-
-    public static Map<String, Object> logsForException(Throwable throwable) {
-      final Map<String, Object> errorLogs = new HashMap<>(4);
-      errorLogs.put("event", Tags.ERROR.getKey());
-      errorLogs.put("error.kind", throwable.getClass().getName());
-      errorLogs.put("error.object", throwable);
-
-      errorLogs.put("message", throwable.getMessage());
-
-      final StringWriter sw = new StringWriter();
-      throwable.printStackTrace(new PrintWriter(sw));
-      errorLogs.put("stack", sw.toString());
-
-      return errorLogs;
-    }
   }
 
+  @Slf4j
   public static class RequestCallback implements Function1<Result, Result> {
     private final Span span;
 
@@ -208,7 +192,7 @@ public final class PlayInstrumentation extends Instrumenter.Configurable {
       try {
         Tags.HTTP_STATUS.set(span, result.header().status());
       } catch (Throwable t) {
-        LoggerFactory.getLogger(RequestCallback.class).debug("error in play instrumentation", t);
+        log.debug("error in play instrumentation", t);
       }
       span.finish();
       return result;

dd-java-agent/instrumentation/play/src/test/groovy/PlayTest.groovy

@@ -1,5 +1,6 @@
 import datadog.opentracing.DDSpan
 import datadog.trace.agent.test.AgentTestRunner
+import datadog.trace.agent.test.TestUtils
 import okhttp3.OkHttpClient
 import okhttp3.Request
 import play.api.test.TestServer
@@ -12,11 +13,13 @@ class PlayTest extends AgentTestRunner {
     System.setProperty("dd.integration.play.enabled", "true")
   }
 
+  @Shared
+  int port = TestUtils.randomOpenPort()
   @Shared
   TestServer testServer
 
   def setupSpec() {
-    testServer = Helpers.testServer(9080, PlayTestUtils.buildTestApp())
+    testServer = Helpers.testServer(port, PlayTestUtils.buildTestApp())
     testServer.start()
   }
 
@@ -33,7 +36,7 @@ class PlayTest extends AgentTestRunner {
     setup:
     OkHttpClient client = new OkHttpClient.Builder().build()
     def request = new Request.Builder()
-      .url("http://localhost:9080/helloplay/spock")
+      .url("http://localhost:$port/helloplay/spock")
       .header("x-datadog-trace-id", "123")
       .header("x-datadog-parent-id", "456")
       .get()
@@ -69,7 +72,7 @@ class PlayTest extends AgentTestRunner {
     setup:
     OkHttpClient client = new OkHttpClient.Builder().build()
     def request = new Request.Builder()
-      .url("http://localhost:9080/make-error")
+      .url("http://localhost:$port/make-error")
       .get()
       .build()
     def response = client.newCall(request).execute()
@@ -96,7 +99,7 @@ class PlayTest extends AgentTestRunner {
     setup:
     OkHttpClient client = new OkHttpClient.Builder().build()
     def request = new Request.Builder()
-      .url("http://localhost:9080/exception")
+      .url("http://localhost:$port/exception")
       .get()
       .build()
     def response = client.newCall(request).execute()
@@ -126,7 +129,7 @@ class PlayTest extends AgentTestRunner {
     setup:
     OkHttpClient client = new OkHttpClient.Builder().build()
     def request = new Request.Builder()
-      .url("http://localhost:9080/nowhere")
+      .url("http://localhost:$port/nowhere")
       .get()
       .build()
     def response = client.newCall(request).execute()

dd-java-agent/testing/src/main/java/datadog/trace/agent/test/TestUtils.java

@@ -6,6 +6,7 @@ import io.opentracing.Tracer;
 import io.opentracing.util.GlobalTracer;
 import java.io.*;
 import java.lang.reflect.Field;
+import java.net.ServerSocket;
 import java.net.URL;
 import java.util.UUID;
 import java.util.concurrent.Callable;
@@ -160,4 +161,18 @@ public class TestUtils {
     jarOutputStream.write(bytes, 0, bytes.length);
     jarOutputStream.closeEntry();
   }
+
+  /** Open up a random, reusable port. */
+  public static int randomOpenPort() {
+    ServerSocket socket;
+    try {
+      socket = new ServerSocket(0);
+      socket.setReuseAddress(true);
+      socket.close();
+      return socket.getLocalPort();
+    } catch (IOException ioe) {
+      ioe.printStackTrace();
+      return -1;
+    }
+  }
 }