feat: Add SSE transport tests for MCP client and server

- Add tests for HttpServletSseServerTransport implementation
- Add tests for HttpClientSseClientTransport implementation
- Rename STDIO transport test classes for clarity

mcp/src/test/java/org/springframework/ai/mcp/client/ServletSseMcpAsyncClientTests.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.client;
+
+import org.junit.jupiter.api.Timeout;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.wait.strategy.Wait;
+
+import org.springframework.ai.mcp.client.transport.HttpClientSseClientTransport;
+import org.springframework.ai.mcp.spec.ClientMcpTransport;
+
+/**
+ * Tests for the {@link McpSyncClient} with {@link HttpClientSseClientTransport}.
+ *
+ * @author Christian Tzolov
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class ServletSseMcpAsyncClientTests extends AbstractMcpAsyncClientTests {
+
+	String host = "http://localhost:3004";
+
+	// Uses the https://github.com/tzolov/mcp-everything-server-docker-image
+	@SuppressWarnings("resource")
+	GenericContainer<?> container = new GenericContainer<>("docker.io/tzolov/mcp-everything-server:v1")
+		.withLogConsumer(outputFrame -> System.out.println(outputFrame.getUtf8String()))
+		.withExposedPorts(3001)
+		.waitingFor(Wait.forHttp("/").forStatusCode(404));
+
+	@Override
+	protected ClientMcpTransport createMcpTransport() {
+		return new HttpClientSseClientTransport(host);
+	}
+
+	@Override
+	protected void onStart() {
+		container.start();
+		int port = container.getMappedPort(3001);
+		host = "http://" + container.getHost() + ":" + port;
+	}
+
+	@Override
+	protected void onClose() {
+		container.stop();
+	}
+
+}

mcp/src/test/java/org/springframework/ai/mcp/client/ServletSseMcpSyncClientTests.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.client;
+
+import org.junit.jupiter.api.Timeout;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.wait.strategy.Wait;
+
+import org.springframework.ai.mcp.client.transport.HttpClientSseClientTransport;
+import org.springframework.ai.mcp.spec.ClientMcpTransport;
+
+/**
+ * Tests for the {@link McpSyncClient} with {@link HttpClientSseClientTransport}.
+ *
+ * @author Christian Tzolov
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class ServletSseMcpSyncClientTests extends AbstractMcpSyncClientTests {
+
+	String host = "http://localhost:3003";
+
+	// Uses the https://github.com/tzolov/mcp-everything-server-docker-image
+	@SuppressWarnings("resource")
+	GenericContainer<?> container = new GenericContainer<>("docker.io/tzolov/mcp-everything-server:v1")
+		.withLogConsumer(outputFrame -> System.out.println(outputFrame.getUtf8String()))
+		.withExposedPorts(3001)
+		.waitingFor(Wait.forHttp("/").forStatusCode(404));
+
+	@Override
+	protected ClientMcpTransport createMcpTransport() {
+		return new HttpClientSseClientTransport(host);
+	}
+
+	@Override
+	protected void onStart() {
+		container.start();
+		int port = container.getMappedPort(3001);
+		host = "http://" + container.getHost() + ":" + port;
+	}
+
+	@Override
+	protected void onClose() {
+		container.stop();
+	}
+
+}

mcp/src/test/java/org/springframework/ai/mcp/client/StdioMcpAsyncClientTests.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.client;
+
+import org.junit.jupiter.api.Timeout;
+
+import org.springframework.ai.mcp.client.transport.ServerParameters;
+import org.springframework.ai.mcp.client.transport.StdioClientTransport;
+import org.springframework.ai.mcp.spec.ClientMcpTransport;
+
+/**
+ * Tests for the {@link McpAsyncClient} with {@link StdioClientTransport}.
+ *
+ * @author Christian Tzolov
+ * @author Dariusz Jędrzejczyk
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class StdioMcpAsyncClientTests extends AbstractMcpAsyncClientTests {
+
+	@Override
+	protected ClientMcpTransport createMcpTransport() {
+		ServerParameters stdioParams = ServerParameters.builder("npx")
+			.args("-y", "@modelcontextprotocol/server-everything", "dir")
+			.build();
+		return new StdioClientTransport(stdioParams);
+	}
+
+}

mcp/src/test/java/org/springframework/ai/mcp/client/StdioMcpSyncClientTests.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.client;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+
+import org.springframework.ai.mcp.client.transport.ServerParameters;
+import org.springframework.ai.mcp.client.transport.StdioClientTransport;
+import org.springframework.ai.mcp.spec.ClientMcpTransport;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for the {@link McpSyncClient} with {@link StdioClientTransport}.
+ *
+ * @author Christian Tzolov
+ * @author Dariusz Jędrzejczyk
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class StdioMcpSyncClientTests extends AbstractMcpSyncClientTests {
+
+	@Override
+	protected ClientMcpTransport createMcpTransport() {
+		ServerParameters stdioParams = ServerParameters.builder("npx")
+			.args("-y", "@modelcontextprotocol/server-everything", "dir")
+			.build();
+
+		return new StdioClientTransport(stdioParams);
+	}
+
+	@Test
+	void customErrorHandlerShouldReceiveErrors() {
+		AtomicReference<String> receivedError = new AtomicReference<>();
+
+		((StdioClientTransport) mcpTransport).setErrorHandler(error -> receivedError.set(error));
+
+		String errorMessage = "Test error";
+		((StdioClientTransport) mcpTransport).getErrorSink().tryEmitNext(errorMessage);
+
+		assertThat(receivedError.get()).isNotNull().isEqualTo(errorMessage);
+	}
+
+	@Override
+	protected void onStart() {
+	}
+
+	@Override
+	protected void onClose() {
+	}
+
+}

mcp/src/test/java/org/springframework/ai/mcp/server/ServletSseMcpAsyncServerTests.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.server;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Timeout;
+
+import org.springframework.ai.mcp.server.transport.HttpServletSseServerTransport;
+import org.springframework.ai.mcp.spec.ServerMcpTransport;
+
+/**
+ * Tests for {@link McpAsyncServer} using {@link HttpServletSseServerTransport}.
+ *
+ * @author Christian Tzolov
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class ServletSseMcpAsyncServerTests extends AbstractMcpAsyncServerTests {
+
+	@Override
+	protected ServerMcpTransport createMcpTransport() {
+		return new HttpServletSseServerTransport(new ObjectMapper(), "/mcp/message");
+	}
+
+}

mcp/src/test/java/org/springframework/ai/mcp/server/ServletSseMcpSyncServerTests.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.ai.mcp.server;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Timeout;
+
+import org.springframework.ai.mcp.server.transport.HttpServletSseServerTransport;
+import org.springframework.ai.mcp.spec.ServerMcpTransport;
+
+/**
+ * Tests for {@link McpSyncServer} using {@link HttpServletSseServerTransport}.
+ *
+ * @author Christian Tzolov
+ */
+@Timeout(15) // Giving extra time beyond the client timeout
+class ServletSseMcpSyncServerTests extends AbstractMcpSyncServerTests {
+
+	@Override
+	protected ServerMcpTransport createMcpTransport() {
+		return new HttpServletSseServerTransport(new ObjectMapper(), "/mcp/message");
+	}
+
+}