refactor: introduce session-based architecture for MCP server (#31)

This commit introduces a major refactoring of the MCP Java SDK to implement a session-based architecture
for server-side implementations. The changes improve the SDK's ability to handle multiple concurrent
client connections and provide an API better aligned with the MCP specification.

Key changes:

- Introduce McpServerTransportProvider interface to manage client connections
- Rename ClientMcpTransport to McpClientTransport and ServerMcpTransport to McpServerTransport
- Add exchange objects (McpAsyncServerExchange, McpSyncServerExchange) for client interaction
- Update handler signatures to include exchange parameter: (args) -> result to (exchange, args) -> result
- Rename Registration classes to Specification classes
- Update method names (e.g., rootsChangeConsumers to rootsChangeHandlers)
- Deprecate old interfaces and classes for removal in 0.9.0
- Add migration guide (migration-0.8.0.md)

Resolves #9, #15

Co-authored-by: Christian Tzolov <christian.tzolov@broadcom.com>
Signed-off-by: Christian Tzolov <christian.tzolov@broadcom.com>
This commit is contained in:
Dariusz Jędrzejczyk 2025-03-20 18:14:57 +01:00 • committed by Christian Tzolov
commit 34a733509d
6 changed files with 9969 additions and 1127 deletions

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@ -0,0 +1,118 @@
/*
* Copyright 2024-2024 the original author or authors.
*/
package io.modelcontextprotocol.server;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.spec.ServerMcpTransport;
import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.startup.Tomcat;
import org.junit.jupiter.api.Timeout;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.function.RouterFunction;
import org.springframework.web.servlet.function.ServerResponse;
@Deprecated
@Timeout(15)
class WebMvcSseAsyncServerTransportDeprecatedTests extends AbstractMcpAsyncServerDeprecatedTests {
private static final String MESSAGE_ENDPOINT = "/mcp/message";
private static final int PORT = 8181;
private Tomcat tomcat;
private WebMvcSseServerTransport transport;
@Configuration
@EnableWebMvc
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
}
}
private AnnotationConfigWebApplicationContext appContext;
@Override
protected ServerMcpTransport createMcpTransport() {
// Set up Tomcat first
tomcat = new Tomcat();
tomcat.setPort(PORT);
// Set Tomcat base directory to java.io.tmpdir to avoid permission issues
String baseDir = System.getProperty("java.io.tmpdir");
tomcat.setBaseDir(baseDir);
// Use the same directory for document base
Context context = tomcat.addContext("", baseDir);
// Create and configure Spring WebMvc context
appContext = new AnnotationConfigWebApplicationContext();
appContext.register(TestConfig.class);
appContext.setServletContext(context.getServletContext());
appContext.refresh();
// Get the transport from Spring context
transport = appContext.getBean(WebMvcSseServerTransport.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
// dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
// Add servlet to Tomcat and get the wrapper
var wrapper = Tomcat.addServlet(context, "dispatcherServlet", dispatcherServlet);
wrapper.setLoadOnStartup(1);
context.addServletMappingDecoded("/*", "dispatcherServlet");
try {
tomcat.start();
tomcat.getConnector(); // Create and start the connector
}
catch (LifecycleException e) {
throw new RuntimeException("Failed to start Tomcat", e);
}
return transport;
}
@Override
protected void onStart() {
}
@Override
protected void onClose() {
if (transport != null) {
transport.closeGracefully().block();
}
if (appContext != null) {
appContext.close();
}
if (tomcat != null) {
try {
tomcat.stop();
tomcat.destroy();
}
catch (LifecycleException e) {
throw new RuntimeException("Failed to stop Tomcat", e);
}
}
}
}

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@ -5,8 +5,8 @@
package io.modelcontextprotocol.server;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.spec.ServerMcpTransport;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransportProvider;
import io.modelcontextprotocol.spec.McpServerTransportProvider;
import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.startup.Tomcat;
@ -29,20 +29,20 @@ class WebMvcSseAsyncServerTransportTests extends AbstractMcpAsyncServerTests {
private Tomcat tomcat;
private WebMvcSseServerTransport transport;
private McpServerTransportProvider transportProvider;
@Configuration
@EnableWebMvc
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
public WebMvcSseServerTransportProvider webMvcSseServerTransportProvider() {
return new WebMvcSseServerTransportProvider(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransportProvider transportProvider) {
return transportProvider.getRouterFunction();
}
}
@ -50,7 +50,7 @@ class WebMvcSseAsyncServerTransportTests extends AbstractMcpAsyncServerTests {
private AnnotationConfigWebApplicationContext appContext;
@Override
protected ServerMcpTransport createMcpTransport() {
protected McpServerTransportProvider createMcpTransportProvider() {
// Set up Tomcat first
tomcat = new Tomcat();
tomcat.setPort(PORT);
@ -69,7 +69,7 @@ class WebMvcSseAsyncServerTransportTests extends AbstractMcpAsyncServerTests {
appContext.refresh();
// Get the transport from Spring context
transport = appContext.getBean(WebMvcSseServerTransport.class);
transportProvider = appContext.getBean(WebMvcSseServerTransportProvider.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
@ -88,7 +88,7 @@ class WebMvcSseAsyncServerTransportTests extends AbstractMcpAsyncServerTests {
throw new RuntimeException("Failed to start Tomcat", e);
}
return transport;
return transportProvider;
}
@Override
@ -97,8 +97,8 @@ class WebMvcSseAsyncServerTransportTests extends AbstractMcpAsyncServerTests {
@Override
protected void onClose() {
if (transport != null) {
transport.closeGracefully().block();
if (transportProvider != null) {
transportProvider.closeGracefully().block();
}
if (appContext != null) {
appContext.close();

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@ -0,0 +1,508 @@
/*
* Copyright 2024 - 2024 the original author or authors.
*/
package io.modelcontextprotocol.server;
import java.time.Duration;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicReference;
import java.util.function.Function;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.client.McpClient;
import io.modelcontextprotocol.client.transport.HttpClientSseClientTransport;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.spec.McpError;
import io.modelcontextprotocol.spec.McpSchema;
import io.modelcontextprotocol.spec.McpSchema.CallToolResult;
import io.modelcontextprotocol.spec.McpSchema.ClientCapabilities;
import io.modelcontextprotocol.spec.McpSchema.CreateMessageRequest;
import io.modelcontextprotocol.spec.McpSchema.CreateMessageResult;
import io.modelcontextprotocol.spec.McpSchema.InitializeResult;
import io.modelcontextprotocol.spec.McpSchema.Role;
import io.modelcontextprotocol.spec.McpSchema.Root;
import io.modelcontextprotocol.spec.McpSchema.ServerCapabilities;
import io.modelcontextprotocol.spec.McpSchema.Tool;
import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.startup.Tomcat;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import reactor.test.StepVerifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestClient;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.function.RouterFunction;
import org.springframework.web.servlet.function.ServerResponse;
import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
import static org.awaitility.Awaitility.await;
@Deprecated
public class WebMvcSseIntegrationDeprecatedTests {
private static final int PORT = 8183;
private static final String MESSAGE_ENDPOINT = "/mcp/message";
private WebMvcSseServerTransport mcpServerTransport;
McpClient.SyncSpec clientBuilder;
@Configuration
@EnableWebMvc
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
}
}
private Tomcat tomcat;
private AnnotationConfigWebApplicationContext appContext;
@BeforeEach
public void before() {
// Set up Tomcat first
tomcat = new Tomcat();
tomcat.setPort(PORT);
// Set Tomcat base directory to java.io.tmpdir to avoid permission issues
String baseDir = System.getProperty("java.io.tmpdir");
tomcat.setBaseDir(baseDir);
// Use the same directory for document base
Context context = tomcat.addContext("", baseDir);
// Create and configure Spring WebMvc context
appContext = new AnnotationConfigWebApplicationContext();
appContext.register(TestConfig.class);
appContext.setServletContext(context.getServletContext());
appContext.refresh();
// Get the transport from Spring context
mcpServerTransport = appContext.getBean(WebMvcSseServerTransport.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
// dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
// Add servlet to Tomcat and get the wrapper
var wrapper = Tomcat.addServlet(context, "dispatcherServlet", dispatcherServlet);
wrapper.setLoadOnStartup(1);
wrapper.setAsyncSupported(true);
context.addServletMappingDecoded("/*", "dispatcherServlet");
try {
// Configure and start the connector with async support
var connector = tomcat.getConnector();
connector.setAsyncTimeout(3000); // 3 seconds timeout for async requests
tomcat.start();
assertThat(tomcat.getServer().getState() == LifecycleState.STARTED);
}
catch (Exception e) {
throw new RuntimeException("Failed to start Tomcat", e);
}
this.clientBuilder = McpClient.sync(new HttpClientSseClientTransport("http://localhost:" + PORT));
}
@AfterEach
public void after() {
if (mcpServerTransport != null) {
mcpServerTransport.closeGracefully().block();
}
if (appContext != null) {
appContext.close();
}
if (tomcat != null) {
try {
tomcat.stop();
tomcat.destroy();
}
catch (LifecycleException e) {
throw new RuntimeException("Failed to stop Tomcat", e);
}
}
}
// ---------------------------------------
// Sampling Tests
// ---------------------------------------
@Test
void testCreateMessageWithoutInitialization() {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
StepVerifier.create(mcpAsyncServer.createMessage(request)).verifyErrorSatisfies(error -> {
assertThat(error).isInstanceOf(McpError.class)
.hasMessage("Client must be initialized. Call the initialize method first!");
});
}
@Test
void testCreateMessageWithoutSamplingCapabilities() {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
var client = clientBuilder.clientInfo(new McpSchema.Implementation("Sample " + "client", "0.0.0")).build();
InitializeResult initResult = client.initialize();
assertThat(initResult).isNotNull();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
StepVerifier.create(mcpAsyncServer.createMessage(request)).verifyErrorSatisfies(error -> {
assertThat(error).isInstanceOf(McpError.class)
.hasMessage("Client must be configured with sampling capabilities");
});
}
@Test
void testCreateMessageSuccess() throws InterruptedException {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
Function<CreateMessageRequest, CreateMessageResult> samplingHandler = request -> {
assertThat(request.messages()).hasSize(1);
assertThat(request.messages().get(0).content()).isInstanceOf(McpSchema.TextContent.class);
return new CreateMessageResult(Role.USER, new McpSchema.TextContent("Test message"), "MockModelName",
CreateMessageResult.StopReason.STOP_SEQUENCE);
};
var client = clientBuilder.clientInfo(new McpSchema.Implementation("Sample client", "0.0.0"))
.capabilities(ClientCapabilities.builder().sampling().build())
.sampling(samplingHandler)
.build();
InitializeResult initResult = client.initialize();
assertThat(initResult).isNotNull();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
StepVerifier.create(mcpAsyncServer.createMessage(request)).consumeNextWith(result -> {
assertThat(result).isNotNull();
assertThat(result.role()).isEqualTo(Role.USER);
assertThat(result.content()).isInstanceOf(McpSchema.TextContent.class);
assertThat(((McpSchema.TextContent) result.content()).text()).isEqualTo("Test message");
assertThat(result.model()).isEqualTo("MockModelName");
assertThat(result.stopReason()).isEqualTo(CreateMessageResult.StopReason.STOP_SEQUENCE);
}).verifyComplete();
}
// ---------------------------------------
// Roots Tests
// ---------------------------------------
@Test
void testRootsSuccess() {
List<Root> roots = List.of(new Root("uri1://", "root1"), new Root("uri2://", "root2"));
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
.roots(roots)
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
assertThat(rootsRef.get()).isNull();
assertThat(mcpServer.listRoots().roots()).containsAll(roots);
mcpClient.rootsListChangedNotification();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(roots);
});
// Remove a root
mcpClient.removeRoot(roots.get(0).uri());
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(List.of(roots.get(1)));
});
// Add a new root
var root3 = new Root("uri3://", "root3");
mcpClient.addRoot(root3);
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(List.of(roots.get(1), root3));
});
mcpClient.close();
mcpServer.close();
}
@Test
void testRootsWithoutCapability() {
var mcpServer = McpServer.sync(mcpServerTransport).rootsChangeConsumer(rootsUpdate -> {
}).build();
// Create client without roots capability
// No roots capability
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().build()).build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
// Attempt to list roots should fail
assertThatThrownBy(() -> mcpServer.listRoots().roots()).isInstanceOf(McpError.class)
.hasMessage("Roots not supported");
mcpClient.close();
mcpServer.close();
}
@Test
void testRootsWithEmptyRootsList() {
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
.roots(List.of()) // Empty roots list
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
mcpClient.rootsListChangedNotification();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).isEmpty();
});
mcpClient.close();
mcpServer.close();
}
@Test
void testRootsWithMultipleConsumers() {
List<Root> roots = List.of(new Root("uri1://", "root1"));
AtomicReference<List<Root>> rootsRef1 = new AtomicReference<>();
AtomicReference<List<Root>> rootsRef2 = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef1.set(rootsUpdate))
.rootsChangeConsumer(rootsUpdate -> rootsRef2.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
.roots(roots)
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
mcpClient.rootsListChangedNotification();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef1.get()).containsAll(roots);
assertThat(rootsRef2.get()).containsAll(roots);
});
mcpClient.close();
mcpServer.close();
}
@Test
void testRootsServerCloseWithActiveSubscription() {
List<Root> roots = List.of(new Root("uri1://", "root1"));
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
.roots(roots)
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
mcpClient.rootsListChangedNotification();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(roots);
});
// Close server while subscription is active
mcpServer.close();
// Verify client can handle server closure gracefully
mcpClient.close();
}
// ---------------------------------------
// Tools Tests
// ---------------------------------------
String emptyJsonSchema = """
{
"$schema": "http://json-schema.org/draft-07/schema#",
"type": "object",
"properties": {}
}
""";
@Test
void testToolCallSuccess() {
var callResponse = new McpSchema.CallToolResult(List.of(new McpSchema.TextContent("CALL RESPONSE")), null);
McpServerFeatures.SyncToolRegistration tool1 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), request -> {
// perform a blocking call to a remote service
String response = RestClient.create()
.get()
.uri("https://github.com/modelcontextprotocol/specification/blob/main/README.md")
.retrieve()
.body(String.class);
assertThat(response).isNotBlank();
return callResponse;
});
var mcpServer = McpServer.sync(mcpServerTransport)
.capabilities(ServerCapabilities.builder().tools(true).build())
.tools(tool1)
.build();
var mcpClient = clientBuilder.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
assertThat(mcpClient.listTools().tools()).contains(tool1.tool());
CallToolResult response = mcpClient.callTool(new McpSchema.CallToolRequest("tool1", Map.of()));
assertThat(response).isNotNull();
assertThat(response).isEqualTo(callResponse);
mcpClient.close();
mcpServer.close();
}
@Test
void testToolListChangeHandlingSuccess() {
var callResponse = new McpSchema.CallToolResult(List.of(new McpSchema.TextContent("CALL RESPONSE")), null);
McpServerFeatures.SyncToolRegistration tool1 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), request -> {
// perform a blocking call to a remote service
String response = RestClient.create()
.get()
.uri("https://github.com/modelcontextprotocol/specification/blob/main/README.md")
.retrieve()
.body(String.class);
assertThat(response).isNotBlank();
return callResponse;
});
var mcpServer = McpServer.sync(mcpServerTransport)
.capabilities(ServerCapabilities.builder().tools(true).build())
.tools(tool1)
.build();
AtomicReference<List<Tool>> rootsRef = new AtomicReference<>();
var mcpClient = clientBuilder.toolsChangeConsumer(toolsUpdate -> {
// perform a blocking call to a remote service
String response = RestClient.create()
.get()
.uri("https://github.com/modelcontextprotocol/specification/blob/main/README.md")
.retrieve()
.body(String.class);
assertThat(response).isNotBlank();
rootsRef.set(toolsUpdate);
}).build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
assertThat(rootsRef.get()).isNull();
assertThat(mcpClient.listTools().tools()).contains(tool1.tool());
mcpServer.notifyToolsListChanged();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(List.of(tool1.tool()));
});
// Remove a tool
mcpServer.removeTool("tool1");
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).isEmpty();
});
// Add a new tool
McpServerFeatures.SyncToolRegistration tool2 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool2", "tool2 description", emptyJsonSchema), request -> callResponse);
mcpServer.addTool(tool2);
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
assertThat(rootsRef.get()).containsAll(List.of(tool2.tool()));
});
mcpClient.close();
mcpServer.close();
}
@Test
void testInitialize() {
var mcpServer = McpServer.sync(mcpServerTransport).build();
var mcpClient = clientBuilder.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
mcpClient.close();
mcpServer.close();
}
}

View file

@ -12,7 +12,7 @@ import java.util.function.Function;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.client.McpClient;
import io.modelcontextprotocol.client.transport.HttpClientSseClientTransport;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransportProvider;
import io.modelcontextprotocol.spec.McpError;
import io.modelcontextprotocol.spec.McpSchema;
import io.modelcontextprotocol.spec.McpSchema.CallToolResult;
@ -31,6 +31,7 @@ import org.apache.catalina.startup.Tomcat;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import reactor.core.publisher.Mono;
import reactor.test.StepVerifier;
import org.springframework.context.annotation.Bean;
@ -43,8 +44,8 @@ import org.springframework.web.servlet.function.RouterFunction;
import org.springframework.web.servlet.function.ServerResponse;
import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
import static org.awaitility.Awaitility.await;
import static org.mockito.Mockito.mock;
public class WebMvcSseIntegrationTests {
@ -52,7 +53,7 @@ public class WebMvcSseIntegrationTests {
private static final String MESSAGE_ENDPOINT = "/mcp/message";
private WebMvcSseServerTransport mcpServerTransport;
private WebMvcSseServerTransportProvider mcpServerTransportProvider;
McpClient.SyncSpec clientBuilder;
@ -61,13 +62,13 @@ public class WebMvcSseIntegrationTests {
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
public WebMvcSseServerTransportProvider webMvcSseServerTransportProvider() {
return new WebMvcSseServerTransportProvider(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransportProvider transportProvider) {
return transportProvider.getRouterFunction();
}
}
@ -97,7 +98,7 @@ public class WebMvcSseIntegrationTests {
appContext.refresh();
// Get the transport from Spring context
mcpServerTransport = appContext.getBean(WebMvcSseServerTransport.class);
mcpServerTransportProvider = appContext.getBean(WebMvcSseServerTransportProvider.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
@ -125,8 +126,8 @@ public class WebMvcSseIntegrationTests {
@AfterEach
public void after() {
if (mcpServerTransport != null) {
mcpServerTransport.closeGracefully().block();
if (mcpServerTransportProvider != null) {
mcpServerTransportProvider.closeGracefully().block();
}
if (appContext != null) {
appContext.close();
@ -145,50 +146,37 @@ public class WebMvcSseIntegrationTests {
// ---------------------------------------
// Sampling Tests
// ---------------------------------------
@Test
void testCreateMessageWithoutInitialization() {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
StepVerifier.create(mcpAsyncServer.createMessage(request)).verifyErrorSatisfies(error -> {
assertThat(error).isInstanceOf(McpError.class)
.hasMessage("Client must be initialized. Call the initialize method first!");
});
}
@Test
void testCreateMessageWithoutSamplingCapabilities() {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
McpServerFeatures.AsyncToolSpecification tool = new McpServerFeatures.AsyncToolSpecification(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), (exchange, request) -> {
exchange.createMessage(mock(McpSchema.CreateMessageRequest.class)).block();
return Mono.just(mock(CallToolResult.class));
});
McpServer.async(mcpServerTransportProvider).serverInfo("test-server", "1.0.0").tools(tool).build();
// Create client without sampling capabilities
var client = clientBuilder.clientInfo(new McpSchema.Implementation("Sample " + "client", "0.0.0")).build();
InitializeResult initResult = client.initialize();
assertThat(initResult).isNotNull();
assertThat(client.initialize()).isNotNull();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
StepVerifier.create(mcpAsyncServer.createMessage(request)).verifyErrorSatisfies(error -> {
assertThat(error).isInstanceOf(McpError.class)
try {
client.callTool(new McpSchema.CallToolRequest("tool1", Map.of()));
}
catch (McpError e) {
assertThat(e).isInstanceOf(McpError.class)
.hasMessage("Client must be configured with sampling capabilities");
});
}
}
@Test
void testCreateMessageSuccess() throws InterruptedException {
var mcpAsyncServer = McpServer.async(mcpServerTransport).serverInfo("test-server", "1.0.0").build();
// Client
Function<CreateMessageRequest, CreateMessageResult> samplingHandler = request -> {
assertThat(request.messages()).hasSize(1);
@ -198,29 +186,54 @@ public class WebMvcSseIntegrationTests {
CreateMessageResult.StopReason.STOP_SEQUENCE);
};
var client = clientBuilder.clientInfo(new McpSchema.Implementation("Sample client", "0.0.0"))
var mcpClient = clientBuilder.clientInfo(new McpSchema.Implementation("Sample client", "0.0.0"))
.capabilities(ClientCapabilities.builder().sampling().build())
.sampling(samplingHandler)
.build();
InitializeResult initResult = client.initialize();
// Server
CallToolResult callResponse = new McpSchema.CallToolResult(List.of(new McpSchema.TextContent("CALL RESPONSE")),
null);
McpServerFeatures.AsyncToolSpecification tool = new McpServerFeatures.AsyncToolSpecification(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), (exchange, request) -> {
var messages = List.of(new McpSchema.SamplingMessage(McpSchema.Role.USER,
new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
var craeteMessageRequest = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(),
Map.of());
StepVerifier.create(exchange.createMessage(craeteMessageRequest)).consumeNextWith(result -> {
assertThat(result).isNotNull();
assertThat(result.role()).isEqualTo(Role.USER);
assertThat(result.content()).isInstanceOf(McpSchema.TextContent.class);
assertThat(((McpSchema.TextContent) result.content()).text()).isEqualTo("Test message");
assertThat(result.model()).isEqualTo("MockModelName");
assertThat(result.stopReason()).isEqualTo(CreateMessageResult.StopReason.STOP_SEQUENCE);
}).verifyComplete();
return Mono.just(callResponse);
});
var mcpServer = McpServer.async(mcpServerTransportProvider)
.serverInfo("test-server", "1.0.0")
.tools(tool)
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
var messages = List
.of(new McpSchema.SamplingMessage(McpSchema.Role.USER, new McpSchema.TextContent("Test message")));
var modelPrefs = new McpSchema.ModelPreferences(List.of(), 1.0, 1.0, 1.0);
CallToolResult response = mcpClient.callTool(new McpSchema.CallToolRequest("tool1", Map.of()));
var request = new McpSchema.CreateMessageRequest(messages, modelPrefs, null,
McpSchema.CreateMessageRequest.ContextInclusionStrategy.NONE, null, 100, List.of(), Map.of());
assertThat(response).isNotNull();
assertThat(response).isEqualTo(callResponse);
StepVerifier.create(mcpAsyncServer.createMessage(request)).consumeNextWith(result -> {
assertThat(result).isNotNull();
assertThat(result.role()).isEqualTo(Role.USER);
assertThat(result.content()).isInstanceOf(McpSchema.TextContent.class);
assertThat(((McpSchema.TextContent) result.content()).text()).isEqualTo("Test message");
assertThat(result.model()).isEqualTo("MockModelName");
assertThat(result.stopReason()).isEqualTo(CreateMessageResult.StopReason.STOP_SEQUENCE);
}).verifyComplete();
mcpClient.close();
mcpServer.close();
}
// ---------------------------------------
@ -231,8 +244,8 @@ public class WebMvcSseIntegrationTests {
List<Root> roots = List.of(new Root("uri1://", "root1"), new Root("uri2://", "root2"));
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.rootsChangeHandler((exchange, rootsUpdate) -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
@ -244,8 +257,6 @@ public class WebMvcSseIntegrationTests {
assertThat(rootsRef.get()).isNull();
assertThat(mcpServer.listRoots().roots()).containsAll(roots);
mcpClient.rootsListChangedNotification();
await().atMost(Duration.ofSeconds(5)).untilAsserted(() -> {
@ -273,29 +284,42 @@ public class WebMvcSseIntegrationTests {
@Test
void testRootsWithoutCapability() {
var mcpServer = McpServer.sync(mcpServerTransport).rootsChangeConsumer(rootsUpdate -> {
}).build();
McpServerFeatures.SyncToolSpecification tool = new McpServerFeatures.SyncToolSpecification(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), (exchange, request) -> {
exchange.listRoots(); // try to list roots
return mock(CallToolResult.class);
});
var mcpServer = McpServer.sync(mcpServerTransportProvider).rootsChangeHandler((exchange, rootsUpdate) -> {
}).tools(tool).build();
// Create client without roots capability
// No roots capability
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().build()).build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
assertThat(mcpClient.initialize()).isNotNull();
// Attempt to list roots should fail
assertThatThrownBy(() -> mcpServer.listRoots().roots()).isInstanceOf(McpError.class)
.hasMessage("Roots not supported");
try {
mcpClient.callTool(new McpSchema.CallToolRequest("tool1", Map.of()));
}
catch (McpError e) {
assertThat(e).isInstanceOf(McpError.class).hasMessage("Roots not supported");
}
mcpClient.close();
mcpServer.close();
}
@Test
void testRootsWithEmptyRootsList() {
void testRootsNotifciationWithEmptyRootsList() {
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.rootsChangeHandler((exchange, rootsUpdate) -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
@ -316,23 +340,22 @@ public class WebMvcSseIntegrationTests {
}
@Test
void testRootsWithMultipleConsumers() {
void testRootsWithMultipleHandlers() {
List<Root> roots = List.of(new Root("uri1://", "root1"));
AtomicReference<List<Root>> rootsRef1 = new AtomicReference<>();
AtomicReference<List<Root>> rootsRef2 = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef1.set(rootsUpdate))
.rootsChangeConsumer(rootsUpdate -> rootsRef2.set(rootsUpdate))
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.rootsChangeHandler((exchange, rootsUpdate) -> rootsRef1.set(rootsUpdate))
.rootsChangeHandler((exchange, rootsUpdate) -> rootsRef2.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
.roots(roots)
.build();
InitializeResult initResult = mcpClient.initialize();
assertThat(initResult).isNotNull();
assertThat(mcpClient.initialize()).isNotNull();
mcpClient.rootsListChangedNotification();
@ -350,8 +373,8 @@ public class WebMvcSseIntegrationTests {
List<Root> roots = List.of(new Root("uri1://", "root1"));
AtomicReference<List<Root>> rootsRef = new AtomicReference<>();
var mcpServer = McpServer.sync(mcpServerTransport)
.rootsChangeConsumer(rootsUpdate -> rootsRef.set(rootsUpdate))
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.rootsChangeHandler((exchange, rootsUpdate) -> rootsRef.set(rootsUpdate))
.build();
var mcpClient = clientBuilder.capabilities(ClientCapabilities.builder().roots(true).build())
@ -390,8 +413,8 @@ public class WebMvcSseIntegrationTests {
void testToolCallSuccess() {
var callResponse = new McpSchema.CallToolResult(List.of(new McpSchema.TextContent("CALL RESPONSE")), null);
McpServerFeatures.SyncToolRegistration tool1 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), request -> {
McpServerFeatures.SyncToolSpecification tool1 = new McpServerFeatures.SyncToolSpecification(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), (exchange, request) -> {
// perform a blocking call to a remote service
String response = RestClient.create()
.get()
@ -402,7 +425,7 @@ public class WebMvcSseIntegrationTests {
return callResponse;
});
var mcpServer = McpServer.sync(mcpServerTransport)
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.capabilities(ServerCapabilities.builder().tools(true).build())
.tools(tool1)
.build();
@ -427,8 +450,8 @@ public class WebMvcSseIntegrationTests {
void testToolListChangeHandlingSuccess() {
var callResponse = new McpSchema.CallToolResult(List.of(new McpSchema.TextContent("CALL RESPONSE")), null);
McpServerFeatures.SyncToolRegistration tool1 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), request -> {
McpServerFeatures.SyncToolSpecification tool1 = new McpServerFeatures.SyncToolSpecification(
new McpSchema.Tool("tool1", "tool1 description", emptyJsonSchema), (exchange, request) -> {
// perform a blocking call to a remote service
String response = RestClient.create()
.get()
@ -439,7 +462,7 @@ public class WebMvcSseIntegrationTests {
return callResponse;
});
var mcpServer = McpServer.sync(mcpServerTransport)
var mcpServer = McpServer.sync(mcpServerTransportProvider)
.capabilities(ServerCapabilities.builder().tools(true).build())
.tools(tool1)
.build();
@ -477,8 +500,8 @@ public class WebMvcSseIntegrationTests {
});
// Add a new tool
McpServerFeatures.SyncToolRegistration tool2 = new McpServerFeatures.SyncToolRegistration(
new McpSchema.Tool("tool2", "tool2 description", emptyJsonSchema), request -> callResponse);
McpServerFeatures.SyncToolSpecification tool2 = new McpServerFeatures.SyncToolSpecification(
new McpSchema.Tool("tool2", "tool2 description", emptyJsonSchema), (exchange, request) -> callResponse);
mcpServer.addTool(tool2);
@ -493,7 +516,7 @@ public class WebMvcSseIntegrationTests {
@Test
void testInitialize() {
var mcpServer = McpServer.sync(mcpServerTransport).build();
var mcpServer = McpServer.sync(mcpServerTransportProvider).build();
var mcpClient = clientBuilder.build();

View file

@ -0,0 +1,118 @@
/*
* Copyright 2024-2024 the original author or authors.
*/
package io.modelcontextprotocol.server;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.spec.ServerMcpTransport;
import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.startup.Tomcat;
import org.junit.jupiter.api.Timeout;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.function.RouterFunction;
import org.springframework.web.servlet.function.ServerResponse;
@Deprecated
@Timeout(15)
class WebMvcSseSyncServerTransportDeprecatedTests extends AbstractMcpSyncServerDeprecatedTests {
private static final String MESSAGE_ENDPOINT = "/mcp/message";
private static final int PORT = 8181;
private Tomcat tomcat;
private WebMvcSseServerTransport transport;
@Configuration
@EnableWebMvc
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
}
}
private AnnotationConfigWebApplicationContext appContext;
@Override
protected ServerMcpTransport createMcpTransport() {
// Set up Tomcat first
tomcat = new Tomcat();
tomcat.setPort(PORT);
// Set Tomcat base directory to java.io.tmpdir to avoid permission issues
String baseDir = System.getProperty("java.io.tmpdir");
tomcat.setBaseDir(baseDir);
// Use the same directory for document base
Context context = tomcat.addContext("", baseDir);
// Create and configure Spring WebMvc context
appContext = new AnnotationConfigWebApplicationContext();
appContext.register(TestConfig.class);
appContext.setServletContext(context.getServletContext());
appContext.refresh();
// Get the transport from Spring context
transport = appContext.getBean(WebMvcSseServerTransport.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
// dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
// Add servlet to Tomcat and get the wrapper
var wrapper = Tomcat.addServlet(context, "dispatcherServlet", dispatcherServlet);
wrapper.setLoadOnStartup(1);
context.addServletMappingDecoded("/*", "dispatcherServlet");
try {
tomcat.start();
tomcat.getConnector(); // Create and start the connector
}
catch (LifecycleException e) {
throw new RuntimeException("Failed to start Tomcat", e);
}
return transport;
}
@Override
protected void onStart() {
}
@Override
protected void onClose() {
if (transport != null) {
transport.closeGracefully().block();
}
if (appContext != null) {
appContext.close();
}
if (tomcat != null) {
try {
tomcat.stop();
tomcat.destroy();
}
catch (LifecycleException e) {
throw new RuntimeException("Failed to stop Tomcat", e);
}
}
}
}

View file

@ -5,8 +5,7 @@
package io.modelcontextprotocol.server;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransport;
import io.modelcontextprotocol.spec.ServerMcpTransport;
import io.modelcontextprotocol.server.transport.WebMvcSseServerTransportProvider;
import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.startup.Tomcat;
@ -29,20 +28,20 @@ class WebMvcSseSyncServerTransportTests extends AbstractMcpSyncServerTests {
private Tomcat tomcat;
private WebMvcSseServerTransport transport;
private WebMvcSseServerTransportProvider transportProvider;
@Configuration
@EnableWebMvc
static class TestConfig {
@Bean
public WebMvcSseServerTransport webMvcSseServerTransport() {
return new WebMvcSseServerTransport(new ObjectMapper(), MESSAGE_ENDPOINT);
public WebMvcSseServerTransportProvider webMvcSseServerTransportProvider() {
return new WebMvcSseServerTransportProvider(new ObjectMapper(), MESSAGE_ENDPOINT);
}
@Bean
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransport transport) {
return transport.getRouterFunction();
public RouterFunction<ServerResponse> routerFunction(WebMvcSseServerTransportProvider transportProvider) {
return transportProvider.getRouterFunction();
}
}
@ -50,7 +49,7 @@ class WebMvcSseSyncServerTransportTests extends AbstractMcpSyncServerTests {
private AnnotationConfigWebApplicationContext appContext;
@Override
protected ServerMcpTransport createMcpTransport() {
protected WebMvcSseServerTransportProvider createMcpTransportProvider() {
// Set up Tomcat first
tomcat = new Tomcat();
tomcat.setPort(PORT);
@ -69,7 +68,7 @@ class WebMvcSseSyncServerTransportTests extends AbstractMcpSyncServerTests {
appContext.refresh();
// Get the transport from Spring context
transport = appContext.getBean(WebMvcSseServerTransport.class);
transportProvider = appContext.getBean(WebMvcSseServerTransportProvider.class);
// Create DispatcherServlet with our Spring context
DispatcherServlet dispatcherServlet = new DispatcherServlet(appContext);
@ -88,7 +87,7 @@ class WebMvcSseSyncServerTransportTests extends AbstractMcpSyncServerTests {
throw new RuntimeException("Failed to start Tomcat", e);
}
return transport;
return transportProvider;
}
@Override
@ -97,8 +96,8 @@ class WebMvcSseSyncServerTransportTests extends AbstractMcpSyncServerTests {
@Override
protected void onClose() {
if (transport != null) {
transport.closeGracefully().block();
if (transportProvider != null) {
transportProvider.closeGracefully().block();
}
if (appContext != null) {
appContext.close();