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Fix MCP HTTP server resource leaks and error handling gaps#17

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mars167 merged 8 commits intomainfrom
copilot/fix-mcp-http-connection-issues
Feb 4, 2026
Merged

Fix MCP HTTP server resource leaks and error handling gaps#17
mars167 merged 8 commits intomainfrom
copilot/fix-mcp-http-connection-issues

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Copilot AI commented Feb 3, 2026 •
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Addressed code review feedback on MCP HTTP server implementation. Fixed resource leaks, race conditions, and missing error boundaries.

Resource Management

  • Signal handlers: Changed process.on() → process.once() to prevent duplicate registration on multiple startHttp() calls
  • Shutdown cleanup: Call transport.close() instead of invoking onclose callback directly; wait for all transports to close
  • Connection failures: Added transport.close() in error paths for both stateless and session modes
// Before: callback invocation doesn't actually close transport
for (const [sessionId, session] of sessions.entries()) {
  if (session.transport.onclose) {
    session.transport.onclose();
  }
}

// After: proper async cleanup with Promise.allSettled
const closePromises = [];
for (const [sessionId, session] of sessions.entries()) {
  closePromises.push(session.transport.close());
}
await Promise.allSettled(closePromises);

Error Handling

  • URL parsing: Wrapped in try-catch, returns 400 on malformed URLs
  • Session race condition: Added null check after Map.get(), returns 410 if session deleted between has() and get()
  • Double-delete protection: Guard onclose callback with sessions.has() check

Code Quality

  • Removed dead setupServerHandlers() wrapper method
  • Removed redundant String() type conversion

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Copilot AI and others added 4 commits February 3, 2026 06:41
@mars167
Initial branch creation for MCP HTTP fixes
bce4ce0 
Co-authored-by: mars167 <29228178+mars167@users.noreply.github.com>
@mars167
Fix critical MCP HTTP connection issues
a01046b 
- Add comprehensive error handling for HTTP requests and server connections
- Fix session management to return session ID in response headers
- Eliminate code duplication by consolidating handler setup into attachServerHandlers
- Add graceful shutdown mechanism with SIGTERM/SIGINT handlers
- Store both transport and server instances in session map
- Add proper error handling for stateless mode
- Fix race condition in session initialization

Co-authored-by: mars167 <29228178+mars167@users.noreply.github.com>
@mars167
Update documentation for MCP HTTP improvements
8b4b441 
- Create English MCP documentation (docs/mcp.md)
- Update Chinese MCP documentation with HTTP improvements
- Document session management and persistence
- Document error handling and graceful shutdown
- Update README.md and README.zh-CN.md with HTTP features
- Add session usage examples

Co-authored-by: mars167 <29228178+mars167@users.noreply.github.com>
@mars167
Address code review feedback - remove redundant type cast
4ea5964 
Remove redundant 'as never' cast from Promise<never> return statement

Co-authored-by: mars167 <29228178+mars167@users.noreply.github.com>
Copilot AI changed the title [WIP] Fix issues in MCP HTTP connection implementation Fix MCP HTTP server connection handling and session management Feb 3, 2026
Copilot AI requested a review from mars167 February 3, 2026 06:50
@mars167 mars167 marked this pull request as ready for review February 3, 2026 07:28
@mars167
Address code review feedback - improve error handling and resource ma…
0a7416d 
…nagement

- Change signal handlers from on() to once() to prevent duplicates
- Remove redundant setupServerHandlers() method (dead code)
- Remove redundant String() type conversion
- Add URL parsing error handling with 400 status
- Add session race condition check with 410 status
- Add proper transport cleanup on connection failures
- Improve shutdown to properly close transports instead of just invoking callbacks
- Add defensive check in onclose callback to prevent double-delete

Co-authored-by: mars167 <29228178+mars167@users.noreply.github.com>
Copilot AI changed the title Fix MCP HTTP server connection handling and session management Fix MCP HTTP server resource leaks and error handling gaps Feb 3, 2026
@mars167
Fix MCP search_symbols and repo_map handlers
39e3185 
- Add stripLanguageKeywords() to symbolSearch.ts to remove language keywords (class, function, etc.) from search queries
- Apply keyword stripping in filterAndRankSymbolRows before symbol matching
- Add comprehensive diagnostics to handleRepoMap with detailed logging
- Improve error messages for empty repo_map results with actionable suggestions
- Enhance debugging capabilities for both handlers

These changes improve MCP tool usability by:
1. Allowing natural language queries like 'class Project' instead of just 'Project'
2. Providing clear diagnostic information when searches return no results
3. Better error handling and user guidance for index-related issues
@mars167
fix: regenerate package-lock.json to fix CI npm ci failure
a414527 
The package-lock.json was out of sync with package.json, causing
CI to fail with 'Missing: hono@4.11.7 from lock file' error.

Regenerated lock file by running:
- rm -f package-lock.json
- npm install

Build and all tests verified passing locally.
@mars167 mars167 merged commit 6abfdd6 into main Feb 4, 2026
1 check passed
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