fix: ensure SQL storage initializes in Vercel serverless runtime#314
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FaiChou wants to merge 1 commit intochenyme:mainfrom
Open
fix: ensure SQL storage initializes in Vercel serverless runtime#314FaiChou wants to merge 1 commit intochenyme:mainfrom
FaiChou wants to merge 1 commit intochenyme:mainfrom
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Vercel serverless deployments could start serving requests without reliably executing FastAPI lifespan startup, so config.load() was not always called during cold start. Because SQL schema creation is triggered through storage-backed config/tokens access, PostgreSQL/MySQL tables (for example app_config and tokens) were never initialized even when SERVER_STORAGE_TYPE and SERVER_STORAGE_URL were configured. Add a minimal lazy-init guard in Config with ensure_loaded(), protected by an asyncio lock and a success flag to keep initialization idempotent under concurrent first requests. Wire this guard into an HTTP middleware so initialization is guaranteed before handling requests, and reuse ensure_loaded() in lifespan to preserve existing startup behavior. This keeps the fix small, safe, and backward-compatible while restoring deterministic DB bootstrapping on Vercel.
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this bug: #243 (comment) |
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Summary
Fixes DB schema not initializing on Vercel serverless deployments even when
SERVER_STORAGE_TYPEandSERVER_STORAGE_URLare set.Root cause
Schema bootstrap depends on storage-backed config loading, which was only triggered in FastAPI lifespan startup. In serverless runtime, lifespan may not run reliably before requests.
Changes
config.ensure_loaded()with:_loadedflagasyncio.Lockfor concurrency-safe first loadawait config.ensure_loaded()before handling requestsawait config.load()withawait config.ensure_loaded()Result
Initialization now works in both traditional and serverless runtimes, with minimal and backward-compatible changes.