Package io.modelcontextprotocol.client.transport

Class WebClientStreamableHttpTransport

java.lang.Object

io.modelcontextprotocol.client.transport.WebClientStreamableHttpTransport

All Implemented Interfaces:

io.modelcontextprotocol.spec.McpClientTransport, io.modelcontextprotocol.spec.McpTransport

public class WebClientStreamableHttpTransport
extends Object
implements io.modelcontextprotocol.spec.McpClientTransport

An implementation of the Streamable HTTP protocol as defined by the 2025-03-26 version of the MCP specification.

The transport is capable of resumability and reconnects. It reacts to transport-level session invalidation and will propagate appropriate exceptions to the higher level abstraction layer when needed in order to allow proper state management. The implementation handles servers that are stateful and provide session meta information, but can also communicate with stateless servers that do not provide a session identifier and do not support SSE streams.

This implementation does not handle backwards compatibility with the "HTTP with SSE" transport. In order to communicate over the phased-out 2024-11-05 protocol, use HttpClientSseClientTransport or WebFluxSseClientTransport.

Author:

Dariusz Jędrzejczyk

See Also:

• Streamable HTTP transport specification

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	WebClientStreamableHttpTransport.Builder	Builder for WebClientStreamableHttpTransport.

Method Summary

Modifier and Type	Method	Description
static WebClientStreamableHttpTransport.Builder	builder(org.springframework.web.reactive.function.client.WebClient.Builder webClientBuilder)	Create a stateful builder for creating WebClientStreamableHttpTransport instances.
reactor.core.publisher.Mono<Void>	closeGracefully()
reactor.core.publisher.Mono<Void>	connect(Function<reactor.core.publisher.Mono<io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage>,reactor.core.publisher.Mono<io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage>> handler)
List<String>	protocolVersions()
reactor.core.publisher.Mono<Void>	sendMessage(io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage message)
void	setExceptionHandler(Consumer<Throwable> handler)
<T> T	unmarshalFrom(Object data, io.modelcontextprotocol.json.TypeRef<T> typeRef)

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.McpTransport

close

Method Details

protocolVersions

public List<String> protocolVersions()

Specified by:

protocolVersions in interface io.modelcontextprotocol.spec.McpTransport

builder

public static WebClientStreamableHttpTransport.Builder builder(org.springframework.web.reactive.function.client.WebClient.Builder webClientBuilder)

Create a stateful builder for creating WebClientStreamableHttpTransport instances.

Parameters:

webClientBuilder - the WebClient.Builder to use

Returns:

a builder which will create an instance of WebClientStreamableHttpTransport once WebClientStreamableHttpTransport.Builder.build() is called

connect

public reactor.core.publisher.Mono<Void> connect(Function<reactor.core.publisher.Mono<io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage>,reactor.core.publisher.Mono<io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage>> handler)

Specified by:

connect in interface io.modelcontextprotocol.spec.McpClientTransport

setExceptionHandler

public void setExceptionHandler(Consumer<Throwable> handler)

Specified by:

setExceptionHandler in interface io.modelcontextprotocol.spec.McpClientTransport

closeGracefully

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

Specified by:

closeGracefully in interface io.modelcontextprotocol.spec.McpTransport

sendMessage

public reactor.core.publisher.Mono<Void> sendMessage(io.modelcontextprotocol.spec.McpSchema.JSONRPCMessage message)

Specified by:

sendMessage in interface io.modelcontextprotocol.spec.McpTransport

unmarshalFrom

public <T> T unmarshalFrom(Object data,
 io.modelcontextprotocol.json.TypeRef<T> typeRef)

Specified by:

unmarshalFrom in interface io.modelcontextprotocol.spec.McpTransport