* chore(security,refactor): extract sanitization and improve code quality
- [x] Extract sanitization functions to dedicated sanitization.go module
- [x] Add comprehensive golangci-lint v2 configuration with security rules
- [x] Replace interface{} with any type throughout codebase
- [x] Add admin API authentication security warning
- [x] Extract WebSocket and stats streaming constants
- [x] Add best-effort error handling comments for resource cleanup
- [x] Expand sensitive field patterns for improved PII redaction
- [x] Simplify safety checks and remove redundant nil validations
- [x] Improve test coverage for password field redaction patterns
* refactor: replace interface{} with any type alias
- [x] Replace all `map[string]interface{}` with `map[string]any`
- [x] Replace all `interface{}` with `any` in function signatures and type definitions
- [x] Update sync.Pool New function returns from `interface{}` to `any`
- [x] Add package documentation comments to 8 package files
- [x] Update type assertions and casts to work with `any` type
Under high concurrency, the sync.Pool pattern was creating a race condition
where the same result pointer was being reused by multiple concurrent requests.
The bug:
- parseGraphQLQuery() returns a pointer to 'res' from the pool
- The defer statement returns 'res' back to the pool on function exit
- While the caller is still using the returned pointer, another concurrent
request could get the SAME pointer from the pool and modify it
This caused mutations to randomly get the wrong activeEndpoint value:
- Request A: mutation parsed → activeEndpoint set to :8080 (write)
- Request A: returns pointer to result
- Request A: defer runs → result returned to pool
- Request B: gets SAME pointer from pool
- Request B: query parsed → activeEndpoint overwritten to :8088 (read-only)
- Request A: still holding pointer, now sees :8088 instead of :8080!
- Result: mutation routed to read-only endpoint → database write failure
The fix:
Create a copy of the result before returning, so the pooled object can be
safely reused without affecting the returned value.
lukaszraczyloandGitHub