chore: websocket fixes for cursor example

[NicholasKissel]

No description provided.

[railway-app]

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[NicholasKissel]

• chore: websocket fixes for cursor example #3973 👈 (View in Graphite)
• main

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[claude]

PR Review: WebSocket Fixes for Cursor Example

Summary

This PR makes two key changes to fix WebSocket connections in the cursors-raw-websocket example:

1. Separates HTTP and WebSocket URLs to work around vite-plugin-srvx not proxying WebSocket connections
2. Defaults to "json" encoding when no subprotocol is provided for raw WebSocket connections

Code Quality ✅

Positive aspects:

• Clear, explanatory comments added in both files
• Minimal, focused changes that solve the specific problem
• Follows existing code patterns and conventions

Changes Analysis

1. Frontend URL Separation (App.tsx)

The change splits the HTTP and WebSocket URLs due to vite-plugin-srvx limitations.

Concerns:

• ⚠️ Hardcoded localhost:6420: This will break in production or when RivetKit runs on a different port
• ⚠️ No protocol detection: Hardcodes ws:// instead of using wss:// for secure connections
• This is a workaround rather than a proper solution

Suggestion: Make the WebSocket URL configurable via environment variables or derive it from the HTTP URL with appropriate protocol switching.

2. Default Encoding (router-websocket-endpoints.ts:388)

Defaults to "json" encoding for raw WebSocket connections without subprotocols.

Analysis:

• ✅ Makes sense for raw WebSocket connections which typically use JSON
• ✅ Maintains backward compatibility
• ✅ The comment clearly explains the intent
• ⚠️ Potential breaking change: This changes behavior for raw WebSocket connections that previously would have failed. However, this is likely the desired behavior.

Security Considerations 🔒

• No CORS or origin validation concerns introduced
• EncodingSchema.parse() still validates the encoding value
• Hardcoded localhost URL is not a security issue but could cause environment confusion

Performance Considerations ⚡

• No performance impact from these changes
• The default value (?? operator) has negligible overhead

Test Coverage 🧪

Missing tests:

• No test coverage added for the new default encoding behavior
• This example lacks automated tests for WebSocket connection flow

Recommendation: Add test cases to verify raw WebSocket connections work without explicit encoding subprotocol.

Potential Bugs 🐛

1. Environment-specific failure: The hardcoded ws://localhost:6420 will fail when:

   • Running in production
   • RivetKit is bound to a different port
   • Running in Docker containers with different networking
   • Multiple developers have port conflicts

2. Protocol mismatch: Using ws:// when the app might be served over HTTPS will cause mixed content warnings in browsers

Recommendations 📝

High Priority

1. Make WebSocket URL configurable: Use environment variables or derive from HTTP URL with protocol switching
2. Add tests: Include test coverage for the default encoding behavior

Medium Priority

3. Consider fixing vite-plugin-srvx: Document this limitation or use different dev server configuration
4. Improve error messages: Add connection error handling with helpful messages

Low Priority

5. Protocol detection: Use wss:// when served over HTTPS

Alignment with CLAUDE.md ✅

• ✅ Comments follow the guideline to write as complete sentences
• ✅ Code changes are minimal and focused
• ✅ Follows existing TypeScript patterns in the codebase

Conclusion

The changes solve the immediate problem but introduce environment-specific hardcoding that will cause issues outside of local development. The default encoding change is sound and well-justified.

Recommendation: Request changes to make the WebSocket URL configurable before merging.

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Review generated by Claude Code

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commit: 80fe3e8

[graphite-app]

Merge activity

• Jan 19, 5:04 PM UTC: NathanFlurry added this pull request to the Graphite merge queue.
• Jan 19, 5:04 PM UTC: CI is running for this pull request on a draft pull request (#3974) due to your merge queue CI optimization settings.
• Jan 19, 5:05 PM UTC: Merged by the Graphite merge queue via draft PR: #3974.