Presigned URLs Let Serverless Functions Handle File Uploads Without Proxying Bytes

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Routing file uploads through serverless functions creates problems including doubled bandwidth, high memory usage, and request-size limit failures. Presigned URLs solve this by having the server issue a short-lived, pre-authorized link so the client uploads directly to object storage, bypassing the function entirely. On Neon Functions, developers can generate these URLs using the standard AWS SDK's getSignedUrl method pointed at an S3-compatible storage endpoint. A full test confirmed that the client PUT request reached storage successfully, metadata was saved, and the original file bytes were retrievable. One noted configuration detail is that the injected AWS_REGION variable reflects a storage-cell host rather than a standard region, requiring developers to manually set the region to 'us-east-2'.

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Punk: A Perl MVC Framework That Compiles All Routes at Boot Time

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

One MySQL query consumed 75% of CPU by scanning 16,000 rows to return just 6

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