From f037dd2b76e35f1f9d7a8ad5df58f6eb99d6ef57 Mon Sep 17 00:00:00 2001
From: Lauri Tulmin <ltulmin@splunk.com>
Date: Mon, 10 Apr 2023 20:27:37 +0300
Subject: [PATCH 1/2] Implement HttpServerResponseCustomizer support for
 Grizzly

---
 .../grizzly/GrizzlyHttpResponseMutator.java   | 31 +++++++++++++++++++
 .../HttpServerFilterInstrumentation.java      | 10 ++++++
 .../src/test/groovy/GrizzlyTest.groovy        |  5 +++
 3 files changed, 46 insertions(+)
 create mode 100644 instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java

diff --git a/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java
new file mode 100644
index 000000000000..6880c816bc5e
--- /dev/null
+++ b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.javaagent.instrumentation.grizzly;
+
+import io.opentelemetry.javaagent.bootstrap.http.HttpServerResponseMutator;
+import org.glassfish.grizzly.http.HttpResponsePacket;
+import org.glassfish.grizzly.http.util.DataChunk;
+import org.glassfish.grizzly.http.util.MimeHeaders;
+
+public enum GrizzlyHttpResponseMutator implements HttpServerResponseMutator<HttpResponsePacket> {
+  INSTANCE;
+
+  GrizzlyHttpResponseMutator() {}
+
+  @Override
+  public void appendHeader(HttpResponsePacket response, String name, String value) {
+    MimeHeaders headers = response.getHeaders();
+    DataChunk data = headers.getValue(name);
+    if (data == null) {
+      data = headers.addValue(name);
+    }
+    if (data.getLength() > 0) {
+      data.setString(data.toString() + "," + value);
+    } else {
+      data.setString(value);
+    }
+  }
+}
diff --git a/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/HttpServerFilterInstrumentation.java b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/HttpServerFilterInstrumentation.java
index fcc5d0c9e1da..7b515a73ecca 100644
--- a/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/HttpServerFilterInstrumentation.java
+++ b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/HttpServerFilterInstrumentation.java
@@ -11,6 +11,7 @@
 import static net.bytebuddy.matcher.ElementMatchers.takesArgument;
 
 import io.opentelemetry.context.Context;
+import io.opentelemetry.javaagent.bootstrap.http.HttpServerResponseCustomizerHolder;
 import io.opentelemetry.javaagent.bootstrap.servlet.AppServerBridge;
 import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
 import io.opentelemetry.javaagent.extension.instrumentation.TypeTransformer;
@@ -43,6 +44,15 @@ public void transform(TypeTransformer transformer) {
   @SuppressWarnings("unused")
   public static class PrepareResponseAdvice {
 
+    @Advice.OnMethodEnter(suppress = Throwable.class)
+    public static void onEnter(
+        @Advice.Argument(0) FilterChainContext ctx,
+        @Advice.Argument(2) HttpResponsePacket response) {
+      Context context = GrizzlyStateStorage.getContext(ctx);
+      HttpServerResponseCustomizerHolder.getCustomizer()
+          .customize(context, response, GrizzlyHttpResponseMutator.INSTANCE);
+    }
+
     @Advice.OnMethodExit(onThrowable = Throwable.class, suppress = Throwable.class)
     public static void onExit(
         @Advice.Argument(0) FilterChainContext ctx,
diff --git a/instrumentation/grizzly-2.0/javaagent/src/test/groovy/GrizzlyTest.groovy b/instrumentation/grizzly-2.0/javaagent/src/test/groovy/GrizzlyTest.groovy
index e638be4e0de4..6b9d885f1cb7 100644
--- a/instrumentation/grizzly-2.0/javaagent/src/test/groovy/GrizzlyTest.groovy
+++ b/instrumentation/grizzly-2.0/javaagent/src/test/groovy/GrizzlyTest.groovy
@@ -58,6 +58,11 @@ class GrizzlyTest extends HttpServerTest<HttpServer> implements AgentTestTrait {
     server.stop()
   }
 
+  @Override
+  boolean hasResponseCustomizer(ServerEndpoint endpoint) {
+    true
+  }
+
   @Override
   boolean testCapturedHttpHeaders() {
     false

From 600ef791f39ee5215ff59e862521b21a9b78883d Mon Sep 17 00:00:00 2001
From: Lauri Tulmin <ltulmin@splunk.com>
Date: Wed, 12 Apr 2023 09:29:08 +0300
Subject: [PATCH 2/2] Remove unneeded constructor

---
 .../instrumentation/grizzly/GrizzlyHttpResponseMutator.java     | 2 --
 1 file changed, 2 deletions(-)

diff --git a/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java
index 6880c816bc5e..4e808c5de94a 100644
--- a/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java
+++ b/instrumentation/grizzly-2.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/grizzly/GrizzlyHttpResponseMutator.java
@@ -13,8 +13,6 @@
 public enum GrizzlyHttpResponseMutator implements HttpServerResponseMutator<HttpResponsePacket> {
   INSTANCE;
 
-  GrizzlyHttpResponseMutator() {}
-
   @Override
   public void appendHeader(HttpResponsePacket response, String name, String value) {
     MimeHeaders headers = response.getHeaders();