fix(webflux): fix NoSuchMethodError when using spring framework 7 with webflux

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/pom.xml

@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>co.elastic.apm</groupId>
+        <artifactId>apm-spring-webflux</artifactId>
+        <version>1.56.1-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>apm-spring-webflux-plugin-spring7</artifactId>
+    <name>${project.groupId}:${project.artifactId}</name>
+
+    <properties>
+        <!-- for licence header plugin -->
+        <apm-agent-parent.base.dir>${project.basedir}/../../..</apm-agent-parent.base.dir>
+
+        <animal.sniffer.skip>true</animal.sniffer.skip>
+    </properties>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-dependencies</artifactId>
+                <version>${version.spring-boot-4}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <dependencies>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>apm-spring-webflux-spring5</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <dependency>
+            <!-- through the spring-boot dependency management, the test app will be "updated" to spring boot 4 -->
+            <groupId>${project.groupId}</groupId>
+            <artifactId>apm-spring-webflux-testapp-spring7</artifactId>
+            <version>${project.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-web</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>io.projectreactor</groupId>
+            <artifactId>reactor-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>co.elastic.apm</groupId>
+            <artifactId>apm-spring-webflux-spring5</artifactId>
+            <version>${project.version}</version>
+            <scope>test</scope>
+            <type>test-jar</type>
+        </dependency>
+
+        <!-- required for context-propagation during tests, but only at runtime -->
+        <dependency>
+            <groupId>co.elastic.apm</groupId>
+            <artifactId>apm-reactor-plugin</artifactId>
+            <version>${project.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>co.elastic.apm</groupId>
+            <artifactId>apm-reactor-plugin</artifactId>
+            <version>${project.version}</version>
+            <scope>test</scope>
+            <type>test-jar</type>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.ivy</groupId>
+            <artifactId>ivy</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-dependency-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7HeaderGetterTest.java

@@ -0,0 +1,30 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+public class Spring7HeaderGetterTest extends Spring7Test {
+
+    public Spring7HeaderGetterTest() {
+        super(Impl.class);
+    }
+
+    public static class Impl extends HeaderGetterTest {
+
+    }
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7ServerAnnotatedInstrumentationTest.java

@@ -0,0 +1,30 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+
+public class Spring7ServerAnnotatedInstrumentationTest extends Spring7Test {
+
+    public Spring7ServerAnnotatedInstrumentationTest() {
+        super(Impl.class);
+    }
+
+    public static class Impl extends ServerAnnotatedInstrumentationTest {
+    }
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7ServerFunctionalInstrumentationTest.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+public class Spring7ServerFunctionalInstrumentationTest extends Spring7Test {
+
+    public Spring7ServerFunctionalInstrumentationTest() {
+        super(Impl.class);
+    }
+
+    public static class Impl extends ServerFunctionalInstrumentationTest {
+    }
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7ServletContainerTest.java

@@ -0,0 +1,22 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+public class Spring7ServletContainerTest extends ServletContainerTest {
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7Test.java

@@ -0,0 +1,57 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+import org.junit.jupiter.api.Test;
+import org.junit.platform.launcher.Launcher;
+import org.junit.platform.launcher.LauncherDiscoveryRequest;
+import org.junit.platform.launcher.core.LauncherDiscoveryRequestBuilder;
+import org.junit.platform.launcher.core.LauncherFactory;
+import org.junit.platform.launcher.listeners.SummaryGeneratingListener;
+import org.junit.platform.launcher.listeners.TestExecutionSummary;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.platform.engine.discovery.DiscoverySelectors.selectClass;
+
+abstract class Spring7Test {
+    private Class<?> actualTestClass;
+
+    public Spring7Test(Class<?> testClazz) {
+        this.actualTestClass = testClazz;
+    }
+
+    @Test
+    public void runTests() {
+        LauncherDiscoveryRequest request = LauncherDiscoveryRequestBuilder.request()
+            .selectors(selectClass(actualTestClass))
+            .build();
+        Launcher launcher = LauncherFactory.create();
+        SummaryGeneratingListener listener = new SummaryGeneratingListener();
+        launcher.registerTestExecutionListeners(listener);
+        launcher.execute(request);
+
+        for (TestExecutionSummary.Failure failure : listener.getSummary().getFailures()) {
+            System.out.println(failure);
+            failure.getException().printStackTrace();
+        }
+        assertThat(listener.getSummary().getTestsFailedCount())
+            .describedAs("at least one test failure reported, see stack trace for investigation")
+            .isZero();
+    }
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-plugin-spring7/src/test/java/co/elastic/apm/agent/springwebflux/Spring7WebSocketServerInstrumentationTest.java

@@ -0,0 +1,23 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package co.elastic.apm.agent.springwebflux;
+
+
+public class Spring7WebSocketServerInstrumentationTest extends WebSocketServerInstrumentationTest {
+}

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-spring5/src/main/java/co/elastic/apm/agent/springwebflux/WebfluxHelper.java

@@ -58,7 +58,10 @@
 import java.net.InetSocketAddress;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.stream.Collectors;
 
 import static co.elastic.apm.agent.tracer.AbstractSpan.PRIORITY_HIGH_LEVEL_FRAMEWORK;
 import static co.elastic.apm.agent.tracer.AbstractSpan.PRIORITY_LOW_LEVEL_FRAMEWORK;
@@ -313,7 +316,13 @@ private static void fillResponse(Transaction<?> transaction, ServerWebExchange e
     }
 
     private static void copyHeaders(HttpHeaders source, PotentiallyMultiValuedMap destination) {
-        for (Map.Entry<String, List<String>> header : source.entrySet()) {
+        // This ensures we can make a MultiValueMap without having access
+        // to the api from spring framework 7 that will work across versions 5, 6 and 7
+        Java7IdentityFunction identityFunction = new Java7IdentityFunction();
+        MultiValueCollectorFunction multiValueCollectorFunction = new MultiValueCollectorFunction(source);
+        Map<String, List<String>> multiValueHeaderMap = source.toSingleValueMap().keySet()
+            .stream().collect(Collectors.toMap(identityFunction, multiValueCollectorFunction));
+        for (Map.Entry<String, List<String>> header : multiValueHeaderMap.entrySet()) {
             for (String value : header.getValue()) {
                 destination.add(header.getKey(), value);
             }
@@ -328,4 +337,27 @@ private static void copyCookies(MultiValueMap<String, HttpCookie> source, Potent
         }
     }
 
+    // Due to -source 7, lambdas cannot be used for the collector
+    private static class MultiValueCollectorFunction implements Function<String, List<String>> {
+        private final HttpHeaders source;
+
+        public MultiValueCollectorFunction(HttpHeaders source) {
+            this.source = source;
+        }
+
+        @Override
+        public List<String> apply(String key) {
+            return Objects.requireNonNull(source.getValuesAsList(key));
+        }
+    }
+
+    // Due to -source 7, static method invocations cannot be used
+    private static class Java7IdentityFunction implements Function<String, String> {
+        public Java7IdentityFunction() {}
+
+        @Override
+        public String apply(String key) {
+            return key;
+        }
+    }
 }

apm-agent-plugins/apm-spring-webflux/apm-spring-webflux-spring5/src/test/java/co/elastic/apm/agent/springwebflux/AbstractServerInstrumentationTest.java

@@ -39,11 +39,13 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.CsvSource;
 import org.springframework.core.SpringVersion;
+import org.springframework.http.HttpStatus;
 import org.springframework.http.codec.ServerSentEvent;
 import org.springframework.web.reactive.function.client.WebClientResponseException;
 import reactor.core.publisher.Hooks;
 import reactor.test.StepVerifier;
 
+import java.lang.reflect.Field;
 import java.time.Duration;
 import java.util.Arrays;
 import java.util.List;
@@ -140,8 +142,8 @@ private void hello(boolean expectHeaders) {
                 .describedAs("non-standard request headers should be captured")
                 .isEqualTo("12345");
 
-            assertThat(headers.getFirst("Accept"))
-                .isEqualTo("text/plain, application/json");
+            assertThat(headers.getAll("Accept"))
+                .containsAll(List.of("text/plain" , "application/json"));
 
             assertThat(request.getCookies()
                 .getFirst("cookie"))
@@ -209,6 +211,15 @@ private static int getStatusCode(WebClientResponseException exception) {
         } catch (Exception | Error e) {
             // silently ignored
         }
+        try {
+            // Due to the many breaking changes in the spring framework API in version 7, we have to access the status code through reflection.
+            // This will check if it can retrieve the int code via the HttpStatus.value() method, as getRawStatusCode() has been removed in 7
+            Field statusCode = exception.getClass().getSuperclass().getDeclaredField("statusCode");
+            statusCode.setAccessible(true);
+            return ((HttpStatus)statusCode.get(exception)).value();
+        } catch (Exception | Error e) {
+            // silently ignored
+        }
         try {
             return exception.getRawStatusCode();
         } catch (Exception | Error e) {