fix

Author: zeitlinger

instrumentation/spring/spring-web/spring-web-3.1/library/src/main/java/io/opentelemetry/instrumentation/spring/web/v3_1/HeaderUtil.java

@@ -3,15 +3,14 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package io.opentelemetry.instrumentation.spring.web.v3_1;
+package io.opentelemetry.instrumentation.spring.webflux.v5_3;
 
 import static java.util.Collections.emptyList;
 
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
 import java.util.List;
-import java.util.Map;
 import javax.annotation.Nullable;
 import org.springframework.http.HttpHeaders;
 
@@ -20,7 +19,14 @@ class HeaderUtil {
 
   static {
     // since spring web 7.0
-    GET_HEADERS = findGetHeadersMethod(MethodType.methodType(List.class, String.class, List.class));
+    MethodHandle methodHandle =
+        findGetHeadersMethod(MethodType.methodType(List.class, String.class));
+    if (methodHandle == null) {
+      // up to spring web 7.0
+      methodHandle =
+          findGetHeadersMethod(MethodType.methodType(List.class, Object.class));
+    }
+    GET_HEADERS = methodHandle;
   }
 
   private static MethodHandle findGetHeadersMethod(MethodType methodType) {
@@ -31,18 +37,15 @@ private static MethodHandle findGetHeadersMethod(MethodType methodType) {
     }
   }
 
-  // before spring web 7.0 HttpHeaders implements Map<String, List<String>>, this triggers
-  // errorprone BadInstanceof warning since errorpone is not aware that this instanceof check does
-  // not pass with spring web 7.0+
-  @SuppressWarnings({"unchecked", "BadInstanceof"})
+  @SuppressWarnings("unchecked") // casting MethodHandle.invoke result
   static List<String> getHeader(HttpHeaders headers, String name) {
-    if (headers instanceof Map) {
-      // before spring web 7.0
-      return ((Map<String, List<String>>) headers).getOrDefault(name, emptyList());
-    } else if (GET_HEADERS != null) {
-      // spring web 7.0
+    if (GET_HEADERS != null) {
       try {
-        return (List<String>) GET_HEADERS.invoke(headers, name, emptyList());
+        List<String> result = (List<String>) GET_HEADERS.invoke(headers, name);
+        if (result == null) {
+          return emptyList();
+        }
+        return result;
       } catch (Throwable t) {
         // ignore
       }

instrumentation/spring/spring-webflux/spring-webflux-5.3/library/src/main/java/io/opentelemetry/instrumentation/spring/webflux/v5_3/internal/WebClientHttpAttributesGetter.java

@@ -5,9 +5,15 @@
 
 package io.opentelemetry.instrumentation.spring.webflux.v5_3.internal;
 
+import static java.util.Collections.emptyList;
+
 import io.opentelemetry.instrumentation.api.semconv.http.HttpClientAttributesGetter;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
 import java.util.List;
 import javax.annotation.Nullable;
+import org.springframework.http.HttpHeaders;
 import org.springframework.web.reactive.function.client.ClientRequest;
 import org.springframework.web.reactive.function.client.ClientResponse;
 
@@ -19,6 +25,28 @@ public enum WebClientHttpAttributesGetter
     implements HttpClientAttributesGetter<ClientRequest, ClientResponse> {
   INSTANCE;
 
+  private static final MethodHandle GET_HEADERS;
+
+  static {
+    // since webflux 7.0
+    MethodHandle methodHandle =
+        findGetHeadersMethod(MethodType.methodType(List.class, String.class));
+    if (methodHandle == null) {
+      // up to webflux 7.0
+      methodHandle =
+          findGetHeadersMethod(MethodType.methodType(List.class, Object.class));
+    }
+    GET_HEADERS = methodHandle;
+  }
+
+  private static MethodHandle findGetHeadersMethod(MethodType methodType) {
+    try {
+      return MethodHandles.lookup().findVirtual(HttpHeaders.class, "get", methodType);
+    } catch (Throwable t) {
+      return null;
+    }
+  }
+
   @Override
   public String getUrlFull(ClientRequest request) {
     return request.url().toString();
@@ -30,8 +58,20 @@ public String getHttpRequestMethod(ClientRequest request) {
   }
 
   @Override
+  @SuppressWarnings("unchecked") // casting MethodHandle.invoke result
   public List<String> getHttpRequestHeader(ClientRequest request, String name) {
-    return HeaderUtil.getHeader(request.headers(), name);
+    if (GET_HEADERS != null) {
+      try {
+        List<String> result = (List<String>) GET_HEADERS.invoke(request, name);
+        if (result == null) {
+          return emptyList();
+        }
+        return result;
+      } catch (Throwable t) {
+        // ignore
+      }
+    }
+    return emptyList();
   }
 
   @Override