io.modelcontextprotocol.spec

Class McpStreamableServerSession

java.lang.Object

io.modelcontextprotocol.spec.McpStreamableServerSession

All Implemented Interfaces:

McpLoggableSession, McpSession

public class McpStreamableServerSession
extends Object
implements McpLoggableSession

Representation of a Streamable HTTP server session that keeps track of mapping server-initiated requests to the client and mapping arriving responses. It also allows handling incoming notifications. For requests, it provides the default SSE streaming capability without the insight into the transport-specific details of HTTP handling.

Author:

Dariusz Jędrzejczyk

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	McpStreamableServerSession.Factory Factory for new Streamable HTTP MCP sessions.
static interface	McpStreamableServerSession.InitRequestHandler Request handler for the initialization request.
static class	McpStreamableServerSession.McpStreamableServerSessionInit Composite holding the McpStreamableServerSession and the initialization result
class	McpStreamableServerSession.McpStreamableServerSessionStream An individual SSE stream within a Streamable HTTP context.
static class	McpStreamableServerSession.MethodNotFoundError

Constructor Summary

Constructors

Constructor and Description
McpStreamableServerSession(String id, McpSchema.ClientCapabilities clientCapabilities, McpSchema.Implementation clientInfo, Duration requestTimeout, Map<String,McpRequestHandler<?>> requestHandlers, Map<String,McpNotificationHandler> notificationHandlers) Create an instance of the streamable session.

Method Summary

Modifier and Type	Method and Description
reactor.core.publisher.Mono<Void>	accept(McpSchema.JSONRPCNotification notification) Handle the MCP notification.
reactor.core.publisher.Mono<Void>	accept(McpSchema.JSONRPCResponse response) Handle the MCP response.
void	close() Closes the session and releases any associated resources.
reactor.core.publisher.Mono<Void>	closeGracefully() Closes the session and releases any associated resources asynchronously.
reactor.core.publisher.Mono<Void>	delete()
String	getId() Return the Session ID.
boolean	isNotificationForLevelAllowed(McpSchema.LoggingLevel loggingLevel) Allows checking whether a particular logging level is allowed.
McpStreamableServerSession.McpStreamableServerSessionStream	listeningStream(McpStreamableServerTransport transport) Create a listening stream (the generic HTTP GET request without Last-Event-ID header).
reactor.core.publisher.Flux<McpSchema.JSONRPCMessage>	replay(Object lastEventId)
reactor.core.publisher.Mono<Void>	responseStream(McpSchema.JSONRPCRequest jsonrpcRequest, McpStreamableServerTransport transport) Provide the SSE stream of MCP messages finalized with a Response.
reactor.core.publisher.Mono<Void>	sendNotification(String method, Object params) Sends a notification to the model client or server with parameters.
<T> reactor.core.publisher.Mono<T>	sendRequest(String method, Object requestParams, com.fasterxml.jackson.core.type.TypeReference<T> typeRef) Sends a request to the model counterparty and expects a response of type T.
void	setMinLoggingLevel(McpSchema.LoggingLevel minLoggingLevel) Set the minimum logging level for the client.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface io.modelcontextprotocol.spec.McpSession

sendNotification

Constructor Detail

McpStreamableServerSession

public McpStreamableServerSession(String id,
                                  McpSchema.ClientCapabilities clientCapabilities,
                                  McpSchema.Implementation clientInfo,
                                  Duration requestTimeout,
                                  Map<String,McpRequestHandler<?>> requestHandlers,
                                  Map<String,McpNotificationHandler> notificationHandlers)

Create an instance of the streamable session.

Parameters:

id - session ID

clientCapabilities - client capabilities

clientInfo - client info

requestTimeout - timeout to use for requests

requestHandlers - the map of MCP request handlers keyed by method name

notificationHandlers - the map of MCP notification handlers keyed by method name

Method Detail

setMinLoggingLevel

public void setMinLoggingLevel(McpSchema.LoggingLevel minLoggingLevel)

Description copied from interface: McpLoggableSession

Set the minimum logging level for the client. Messages below this level will be filtered out.

Specified by:

setMinLoggingLevel in interface McpLoggableSession

Parameters:

minLoggingLevel - The minimum logging level

isNotificationForLevelAllowed

public boolean isNotificationForLevelAllowed(McpSchema.LoggingLevel loggingLevel)

Description copied from interface: McpLoggableSession

Allows checking whether a particular logging level is allowed.

Specified by:

isNotificationForLevelAllowed in interface McpLoggableSession

Parameters:

loggingLevel - the level to check

Returns:

whether the logging at the specified level is permitted.

getId

public String getId()

Return the Session ID.

Returns:

session ID

sendRequest

public <T> reactor.core.publisher.Mono<T> sendRequest(String method,
                                                      Object requestParams,
                                                      com.fasterxml.jackson.core.type.TypeReference<T> typeRef)

Description copied from interface: McpSession

Sends a request to the model counterparty and expects a response of type T.

This method handles the request-response pattern where a response is expected from the client or server. The response type is determined by the provided TypeReference.

Specified by:

sendRequest in interface McpSession

Type Parameters:

T - the type of the expected response

Parameters:

method - the name of the method to be called on the counterparty

requestParams - the parameters to be sent with the request

typeRef - the TypeReference describing the expected response type

Returns:

a Mono that will emit the response when received

sendNotification

public reactor.core.publisher.Mono<Void> sendNotification(String method,
                                                          Object params)

Description copied from interface: McpSession

Sends a notification to the model client or server with parameters.

Similar to McpSession.sendNotification(String) but allows sending additional parameters with the notification.

Specified by:

sendNotification in interface McpSession

Parameters:

method - the name of the notification method to be sent to the counterparty

params - parameters to be sent with the notification

Returns:

a Mono that completes when the notification has been sent

delete

public reactor.core.publisher.Mono<Void> delete()

listeningStream

public McpStreamableServerSession.McpStreamableServerSessionStream listeningStream(McpStreamableServerTransport transport)

Create a listening stream (the generic HTTP GET request without Last-Event-ID header).

Parameters:

transport - The dedicated SSE transport stream

Returns:

a stream representation

replay

public reactor.core.publisher.Flux<McpSchema.JSONRPCMessage> replay(Object lastEventId)

responseStream

public reactor.core.publisher.Mono<Void> responseStream(McpSchema.JSONRPCRequest jsonrpcRequest,
                                                        McpStreamableServerTransport transport)

Provide the SSE stream of MCP messages finalized with a Response.

Parameters:

jsonrpcRequest - the MCP request triggering the stream creation

transport - the SSE transport stream to send messages to

Returns:

Mono which completes once the processing is done

accept

public reactor.core.publisher.Mono<Void> accept(McpSchema.JSONRPCNotification notification)

Handle the MCP notification.

Parameters:

notification - MCP notification

Returns:

Mono which completes upon succesful handling

accept

public reactor.core.publisher.Mono<Void> accept(McpSchema.JSONRPCResponse response)

Handle the MCP response.

Parameters:

response - MCP response to the server-initiated request

Returns:

Mono which completes upon successful processing

closeGracefully

public reactor.core.publisher.Mono<Void> closeGracefully()

Description copied from interface: McpSession

Closes the session and releases any associated resources asynchronously.

Specified by:

closeGracefully in interface McpSession

Returns:

a Mono that completes when the session has been closed.

close

public void close()

Description copied from interface: McpSession

Closes the session and releases any associated resources.

Specified by:

close in interface McpSession