feat(sse): Add support for dynamic route parameters in SSE server

[anhao]

Description

This PR adds support for dynamic route parameters in the SSE server, similar to the routing parameters in the Gin framework. This enhancement allows users to define custom route patterns with parameters (e.g., /:channel/sse) and access these parameters in their message handlers.

Changes

• Added WithSSEPattern option to configure custom route patterns
• Implemented route parameter parsing and matching logic
• Added route parameters context handling in SSE sessions
• Added support for accessing route parameters in message handlers
• Added comprehensive test cases for route parameter functionality

Example Usage

// Create SSE server with custom route pattern
sseServer := server.NewSSEServer(mcpServer,
    server.WithSSEPattern("/:channel/sse"),
    server.WithSSEContextFunc(customContextFunc),
)

// Access route parameters in message handlers
func messageHandler(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
    channel := server.GetRouteParam(ctx, "channel")
    // Use the channel parameter...
}

Summary by CodeRabbit

• New Features

  • Introduced a server-sent events system with dynamic route matching that extracts URL parameters, enhancing real-time messaging and connection logging.
  • Implemented custom context handling for SSE connections, allowing improved message processing based on route parameters.

• Tests

  • Added a test case to verify handling of custom route parameters, ensuring accurate responses and error handling in the SSE server.

[coderabbitai[bot]]

"""

Walkthrough

This pull request introduces a new example and updates the SSE server. A new Go file implements an SSE server using the MCP framework with custom connection context handling and a message handler. Enhancements in the server allow extraction and utilization of route parameters via a new pattern matching mechanism. A corresponding test case validates the dynamic routing functionality by checking proper parameter extraction and message processing.

Changes

File	Change Summary
examples/custom_sse_pattern/main.go	New file implementing an SSE server using the MCP framework. Introduces customContextFunc, messageHandler, and main to log connection details, extract parameters, and register a tool for message sending.
server/sse.go	Added support for route parameters with new types (RouteParams, RouteParamsKey) and functions (GetRouteParam, GetRouteParams, WithSSEPattern). Modified methods (handleSSE, handleMessage, ServeHTTP) to incorporate pattern matching and dynamic route handling using a new helper function matchPath.
server/sse_test.go	Added a new test "Can handle custom route parameters" validating SSE server's dynamic route parameter extraction, connection establishment, message endpoint retrieval, and tool invocation using route parameters.

Possibly related PRs

• mark3labs/mcp-go#32: Extends SSE server's context customization with dynamic route parameter extraction and injection, building on the context callback mechanism introduced in this PR.
• mark3labs/mcp-go#29: Adds a basic ServeHTTP method for fixed SSE and message paths; the current PR builds significantly on this foundation by adding dynamic routing and context enhancements. """

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📒 Files selected for processing (1)

• server/sse.go (10 hunks)

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• server/sse.go

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[anhao]

@ezynda3 Hi! My PR is ready for merge and all checks have passed. Could you please review and merge it into the main branch if everything looks good? Thank you! 🙏

[weibaohui]

I really need this feature.

[viky88]

I really need this feature.

+1

[karngyan]

+1 This will be awesome and works as expected. Lets resolve the conflicts, whenever you get time. @anhao

[anhao]

+1 This will be awesome and works as expected. Lets resolve the conflicts, whenever you get time. @anhao

Thank you, I have resolved the conflict. Could you please check it?

[rwjblue-glean]

I took a crack at an alternative implementation fro allowing the server to be mounted at dynamic paths over in https://github.com/mark3labs/mcp-go/pull/214, the key differences are:

1. The route parsing is independent of mcp-go and can be done by whatever system the host server already uses (e.g. net/http, gorilla/mux, chi, &c)
2. It will work alongside the changes in #179, using a custom session that can be aware of any custom route params and whatnot that might be needed throughout the rest of the system (e.g. in the tool handlers)

@anhao - What do you think?

[anhao]

I took a crack at an alternative implementation fro allowing the server to be mounted at dynamic paths over in #214, the key differences are:

1. The route parsing is independent of mcp-go and can be done by whatever system the host server already uses (e.g. net/http, gorilla/mux, chi, &c)
2. It will work alongside the changes in Manage tools on a per session basis #179, using a custom session that can be aware of any custom route params and whatnot that might be needed throughout the rest of the system (e.g. in the tool handlers)

@anhao - What do you think?

@robert-jackson-glean Sounds good to me! The approach is more flexible . Happy to see it implemented. 👍

[rwjblue-glean]

Just to close the loop here, #214 has landed and is released now. Folks should take a look!