Add tests and support for langchain4j-agent MCP tools

Author: jamesnetherton

.github/reclaim-disk-space.sh

@@ -29,7 +29,7 @@ sudo rm -rf /opt/ghc \
      rm -rf /usr/local/.ghcup \
      rm -rf /usr/local/go \
      rm -rf /usr/local/lib/android \
-     rm -rf /usr/local/lib/node_modules \
+     rm -rf /usr/local/lib/node_modules/parcel \
      rm -rf /usr/local/share/boost \
      rm -rf /usr/local/share/powershell \
      rm -rf /usr/share/dotnet \

extensions/langchain4j-agent/deployment/src/main/java/org/apache/camel/quarkus/component/langchain4j/agent/deployment/Langchain4jAgentProcessor.java

@@ -16,8 +16,16 @@
  */
 package org.apache.camel.quarkus.component.langchain4j.agent.deployment;
 
+import java.util.Set;
+import java.util.stream.Collectors;
+
 import io.quarkus.deployment.annotations.BuildStep;
+import io.quarkus.deployment.builditem.CombinedIndexBuildItem;
 import io.quarkus.deployment.builditem.FeatureBuildItem;
+import io.quarkus.deployment.builditem.nativeimage.ReflectiveClassBuildItem;
+import io.quarkus.deployment.pkg.steps.NativeOrNativeSourcesBuild;
+import org.jboss.jandex.ClassInfo;
+import org.jboss.jandex.DotName;
 
 class Langchain4jAgentProcessor {
     private static final String FEATURE = "camel-langchain4j-agent";
@@ -26,4 +34,21 @@ class Langchain4jAgentProcessor {
     FeatureBuildItem feature() {
         return new FeatureBuildItem(FEATURE);
     }
+
+    @BuildStep(onlyIf = NativeOrNativeSourcesBuild.class)
+    ReflectiveClassBuildItem registerForReflection(CombinedIndexBuildItem combinedIndex) {
+        Set<String> mcpProtocolClasses = combinedIndex.getIndex()
+                .getClassesInPackage("dev.langchain4j.mcp.client.protocol")
+                .stream()
+                .map(ClassInfo::asClass)
+                .map(ClassInfo::name)
+                .map(DotName::toString)
+                .collect(Collectors.toSet());
+
+        return ReflectiveClassBuildItem
+                .builder(mcpProtocolClasses.toArray(new String[0]))
+                .fields(true)
+                .methods(true)
+                .build();
+    }
 }

integration-tests/langchain4j-agent/README.adoc

@@ -4,6 +4,8 @@ By default, the Langchain4j-agent integration tests use WireMock to stub Ollama
 
 To run the `camel-quarkus-langchain4j-agent` integration tests against the real API, you need a Ollama instance running with the `orca-mini` & `granite4:3b` models downloaded.
 
+The MCP client tests require https://nodejs.org/[Node.js] to be installed on the test host.
+
 When Ollama is running, set the following environment variables:
 
 [source,shell]

integration-tests/langchain4j-agent/src/main/java/org/apache/camel/quarkus/component/langchain4j/agent/it/AgentProducers.java

@@ -27,6 +27,8 @@
 import dev.langchain4j.data.document.splitter.DocumentSplitters;
 import dev.langchain4j.data.embedding.Embedding;
 import dev.langchain4j.data.segment.TextSegment;
+import dev.langchain4j.mcp.client.DefaultMcpClient;
+import dev.langchain4j.mcp.client.transport.stdio.StdioMcpTransport;
 import dev.langchain4j.memory.chat.ChatMemoryProvider;
 import dev.langchain4j.memory.chat.MessageWindowChatMemory;
 import dev.langchain4j.model.chat.ChatModel;
@@ -54,6 +56,7 @@
 import org.apache.camel.quarkus.component.langchain4j.agent.it.service.TestPojoAiAgent;
 import org.apache.camel.quarkus.component.langchain4j.agent.it.tool.AdditionTool;
 import org.apache.camel.quarkus.component.langchain4j.agent.it.util.PersistentChatMemoryStore;
+import org.apache.camel.quarkus.component.langchain4j.agent.it.util.ProcessUtils;
 import org.eclipse.microprofile.config.inject.ConfigProperty;
 
 import static java.time.Duration.ofSeconds;
@@ -63,6 +66,9 @@ public class AgentProducers {
     @ConfigProperty(name = "langchain4j.ollama.base-url")
     String baseUrl;
 
+    @ConfigProperty(name = "nodejs.installed")
+    boolean isNodeJSInstaled;
+
     @Produces
     @Identifier("ollamaOrcaMiniModel")
     ChatModel ollamaOrcaMiniModel() {
@@ -221,4 +227,25 @@ Agent agentWithCustomTools(@Identifier("granite4Model") ChatModel chatModel) {
                 .withChatModel(chatModel)
                 .withCustomTools(List.of(new AdditionTool())));
     }
+
+    @Produces
+    @Identifier("agentWithMcpClient")
+    Agent agentWithMcpClient(@Identifier("granite4Model") ChatModel chatModel) {
+        if (isNodeJSInstaled) {
+            return new AgentWithoutMemory(new AgentConfiguration()
+                    .withChatModel(chatModel)
+                    .withMcpClient(new DefaultMcpClient.Builder()
+                            .transport(new StdioMcpTransport.Builder()
+                                    .command(List.of(ProcessUtils.getNpxExecutable(), "-y",
+                                            "@modelcontextprotocol/server-everything"))
+                                    .logEvents(true)
+                                    .build())
+                            .build())
+                    .withMcpToolProviderFilter((mcpClient, toolSpecification) -> {
+                        String toolName = toolSpecification.name().toLowerCase();
+                        return toolName.contains("add") || toolName.contains("echo") || toolName.contains("long");
+                    }));
+        }
+        return null;
+    }
 }

integration-tests/langchain4j-agent/src/main/java/org/apache/camel/quarkus/component/langchain4j/agent/it/Langchain4jAgentResource.java

@@ -26,6 +26,7 @@
 import jakarta.ws.rs.Path;
 import jakarta.ws.rs.Produces;
 import jakarta.ws.rs.QueryParam;
+import jakarta.ws.rs.core.HttpHeaders;
 import jakarta.ws.rs.core.MediaType;
 import jakarta.ws.rs.core.Response;
 import org.apache.camel.Exchange;
@@ -225,4 +226,20 @@ public Response chatWithCustomTools(String userMessage) {
             AdditionTool.reset();
         }
     }
+
+    @Path("/mcp/client")
+    @POST
+    @Consumes(MediaType.TEXT_PLAIN)
+    @Produces(value = { MediaType.TEXT_PLAIN, MediaType.APPLICATION_JSON })
+    public Response chatWithMcpClient(String userMessage) {
+        String result = producerTemplate.to("direct:agent-with-mcp-client")
+                .withBody(userMessage)
+                .request(String.class);
+
+        String contentType = userMessage.contains("JSON") ? MediaType.APPLICATION_JSON : MediaType.TEXT_PLAIN;
+
+        return Response.ok(result.trim())
+                .header(HttpHeaders.CONTENT_TYPE, contentType)
+                .build();
+    }
 }

integration-tests/langchain4j-agent/src/main/java/org/apache/camel/quarkus/component/langchain4j/agent/it/Langchain4jAgentRoutes.java

@@ -16,11 +16,17 @@
  */
 package org.apache.camel.quarkus.component.langchain4j.agent.it;
 
+import jakarta.enterprise.context.ApplicationScoped;
 import org.apache.camel.builder.RouteBuilder;
+import org.eclipse.microprofile.config.inject.ConfigProperty;
 
+@ApplicationScoped
 public class Langchain4jAgentRoutes extends RouteBuilder {
     public static final String USER_JOHN = "John Doe";
 
+    @ConfigProperty(name = "nodejs.installed")
+    boolean isNodeJSInstaled;
+
     @Override
     public void configure() throws Exception {
         from("direct:simple-agent")
@@ -58,5 +64,10 @@ public void configure() throws Exception {
 
         from("direct:agent-with-custom-tools")
                 .to("langchain4j-agent:test-agent-custom-tools?agent=#agentWithCustomTools");
+
+        if (isNodeJSInstaled) {
+            from("direct:agent-with-mcp-client")
+                    .to("langchain4j-agent:test-agent-with-mcp-client?agent=#agentWithMcpClient");
+        }
     }
 }

integration-tests/langchain4j-agent/src/main/java/org/apache/camel/quarkus/component/langchain4j/agent/it/util/ProcessUtils.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF 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 org.apache.camel.quarkus.component.langchain4j.agent.it.util;
+
+import io.smallrye.common.os.OS;
+
+public final class ProcessUtils {
+    private ProcessUtils() {
+        // Utility class
+    }
+
+    public static String getNpxExecutable() {
+        return OS.current().equals(OS.WINDOWS) ? "npx.cmd" : "npx";
+    }
+}

integration-tests/langchain4j-agent/src/main/resources/application.properties

@@ -14,4 +14,5 @@
 ## See the License for the specific language governing permissions and
 ## limitations under the License.
 ## ---------------------------------------------------------------------------
-quarkus.native.resources.includes=rag/*
+quarkus.native.resources.includes=rag/*
+quarkus.http.test-timeout=120S

integration-tests/langchain4j-agent/src/test/java/org/apache/camel/quarkus/component/langchain4j/agent/it/Langchain4jAgentTest.java

@@ -21,10 +21,13 @@
 import io.restassured.RestAssured;
 import org.apache.camel.quarkus.component.langchain4j.agent.it.guardrail.ValidationFailureInputGuardrail;
 import org.apache.camel.quarkus.component.langchain4j.agent.it.guardrail.ValidationFailureOutputGuardrail;
+import org.eclipse.microprofile.config.ConfigProvider;
+import org.junit.jupiter.api.Assumptions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 
 import static org.apache.camel.quarkus.component.langchain4j.agent.it.Langchain4jAgentRoutes.USER_JOHN;
+import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.containsStringIgnoringCase;
 import static org.hamcrest.Matchers.is;
@@ -33,7 +36,7 @@
 import static org.hamcrest.Matchers.startsWith;
 
 @ExtendWith(Langchain4jTestWatcher.class)
-@QuarkusTestResource(OllamaTestResource.class)
+@QuarkusTestResource(Langchain4jAgentTestResource.class)
 @QuarkusTest
 class Langchain4jAgentTest {
     static final String TEST_USER_MESSAGE_SIMPLE = "What is Apache Camel?";
@@ -223,4 +226,25 @@ void agentWithCustomTools() {
                         "result", containsStringIgnoringCase("15"),
                         "toolWasInvoked", is(true));
     }
+
+    @Test
+    void agentWithMcpClient() {
+        boolean isNodeJSInstalled = ConfigProvider.getConfig().getValue("nodejs.installed", boolean.class);
+        Assumptions.assumeTrue(isNodeJSInstalled, "Node.js is not installed");
+
+        RestAssured.given()
+                .body("Please list your available tools. You MUST respond using ONLY valid JSON with tool names as an array. DO NOT add explanations. DO NOT add comments. DO NOT wrap in markdown.")
+                .post("/langchain4j-agent/mcp/client")
+                .then()
+                .statusCode(200)
+                .body(".", containsInAnyOrder("add", "echo", "longRunningOperation"));
+
+        RestAssured.given()
+                .body("Use your available tools to perform a long running operation for 2 seconds with 2 steps. DO NOT use any markdown formatting in the response.")
+                .post("/langchain4j-agent/mcp/client")
+                .then()
+                .statusCode(200)
+                .body(containsStringIgnoringCase(
+                        "operation was executed successfully for a duration of 2 seconds divided into 2 steps"));
+    }
 }

integration-tests/langchain4j-agent/src/test/java/org/apache/camel/quarkus/component/langchain4j/agent/it/OllamaTestResource.java renamed to integration-tests/langchain4j-agent/src/test/java/org/apache/camel/quarkus/component/langchain4j/agent/it/Langchain4jAgentTestResource.java

@@ -22,11 +22,14 @@
 import java.nio.file.Paths;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.TimeUnit;
 
 import com.github.tomakehurst.wiremock.stubbing.StubMapping;
+import org.apache.camel.quarkus.component.langchain4j.agent.it.util.ProcessUtils;
 import org.apache.camel.quarkus.test.wiremock.WireMockTestResourceLifecycleManager;
+import org.junit.jupiter.api.condition.OS;
 
-public class OllamaTestResource extends WireMockTestResourceLifecycleManager {
+public class Langchain4jAgentTestResource extends WireMockTestResourceLifecycleManager {
     private static final String OLLAMA_ENV_URL = "LANGCHAIN4J_OLLAMA_BASE_URL";
 
     @Override
@@ -35,6 +38,7 @@ public Map<String, String> start() {
         String wiremockUrl = properties.get("wiremock.url");
         String url = wiremockUrl != null ? wiremockUrl : getRecordTargetBaseUrl();
         properties.put("langchain4j.ollama.base-url", url);
+        properties.put("nodejs.installed", isNodeJSInstallationExists().toString());
         return properties;
     }
 
@@ -86,4 +90,23 @@ public void stop() {
             Langchain4jTestWatcher.reset();
         }
     }
+
+    private Boolean isNodeJSInstallationExists() {
+        try {
+            // TODO: Suppress MCP tests in GitHub Actions for windows - https://github.com/apache/camel-quarkus/issues/8007
+            if (OS.current().equals(OS.WINDOWS) && System.getenv("CI") != null) {
+                return false;
+            }
+
+            Process process = new ProcessBuilder()
+                    .command(ProcessUtils.getNpxExecutable(), "--version")
+                    .start();
+
+            process.waitFor(10, TimeUnit.SECONDS);
+            return process.exitValue() == 0;
+        } catch (Exception e) {
+            LOG.error("Failed detecting Node.js", e);
+        }
+        return false;
+    }
 }