Work around flaky java http client http/2 tests

instrumentation/java-http-client/javaagent/src/test/java/io/opentelemetry/javaagent/instrumentation/javahttpclient/JavaHttpClientTest.java

@@ -11,8 +11,6 @@
 import io.opentelemetry.instrumentation.testing.junit.http.HttpClientTestOptions;
 import java.net.http.HttpClient;
 import org.junit.jupiter.api.Nested;
-import org.junit.jupiter.api.condition.DisabledForJreRange;
-import org.junit.jupiter.api.condition.JRE;
 import org.junit.jupiter.api.extension.RegisterExtension;
 
 public abstract class JavaHttpClientTest extends AbstractJavaHttpClientTest {
@@ -34,7 +32,6 @@ protected void configureHttpClientBuilder(HttpClient.Builder httpClientBuilder)
     }
   }
 
-  @DisabledForJreRange(min = JRE.JAVA_25) // flaky on jdk25-ea
   @Nested
   static class Http2ClientTest extends JavaHttpClientTest {
 

instrumentation/java-http-client/library/src/test/java/io/opentelemetry/instrumentation/javahttpclient/JavaHttpClientTest.java

@@ -12,8 +12,6 @@
 import java.net.http.HttpClient;
 import java.util.Collections;
 import org.junit.jupiter.api.Nested;
-import org.junit.jupiter.api.condition.DisabledForJreRange;
-import org.junit.jupiter.api.condition.JRE;
 import org.junit.jupiter.api.extension.RegisterExtension;
 
 public abstract class JavaHttpClientTest extends AbstractJavaHttpClientTest {
@@ -41,7 +39,6 @@ protected void configureHttpClientBuilder(HttpClient.Builder httpClientBuilder)
     }
   }
 
-  @DisabledForJreRange(min = JRE.JAVA_25) // flaky on jdk25-ea
   @Nested
   static class Http2ClientTest extends JavaHttpClientTest {
 

instrumentation/java-http-client/testing/src/main/java/io/opentelemetry/instrumentation/javahttpclient/AbstractJavaHttpClientTest.java

@@ -45,6 +45,12 @@ public HttpRequest buildRequest(String method, URI uri, Map<String, String> head
     HttpRequest.Builder requestBuilder =
         HttpRequest.newBuilder().uri(uri).method(method, HttpRequest.BodyPublishers.noBody());
     headers.forEach(requestBuilder::header);
+    if (client.version() == HttpClient.Version.HTTP_2) {
+      // notify HttpClientTestServer that the request comes from java http client using http/2 so
+      // that the server can work around http/2 tests failing with java.io.IOException: RST_STREAM
+      // received
+      requestBuilder.header("java-http-client-http2", "true");
+    }
     if (uri.toString().contains("/read-timeout")) {
       requestBuilder.timeout(READ_TIMEOUT);
     }

testing-common/src/main/java/io/opentelemetry/instrumentation/testing/junit/http/HttpClientTestServer.java

@@ -147,7 +147,15 @@ protected void configure(ServerBuilder sb) throws Exception {
               }
               span.startSpan().end();
 
-              return delegate.serve(ctx, req);
+              // this header is set by java http client http/2 tests
+              // we delay the response a bit to ensure that client can send the full request before
+              // it receives the response
+              // this is a workaround for http/2 tests failing with java.io.IOException: RST_STREAM
+              // received
+              boolean delay = req.headers().get("java-http-client-http2") != null;
+
+              HttpResponse response = delegate.serve(ctx, req);
+              return delay ? HttpResponse.delayed(response, Duration.ofMillis(10)) : response;
             })
         .decorator(LoggingService.newDecorator());
   }