Migrate an internal file-upload API with a 500‑MB file-size limit to App Engine. Which approach should you use?

Using signed URLs to upload files directly to Cloud Storage is the most efficient and scalable solution for migrating a file-upload API to App Engine, especially with a 500 MB file size limit. App Engine has request size limits (typically 32 MB for standard environments), making direct uploads of large files problematic. Signed URLs allow your application to generate a temporary, secure URL that clients can use to upload files directly to a Cloud Storage bucket, bypassing the App Engine instance entirely. This offloads the heavy lifting from App Engine, improving performance and scalability. FTP and CPanel are not suitable for programmatic API integrations in a modern cloud environment like App Engine. Changing the API to be a multipart file upload API would still face the App Engine request size limits if the files are uploaded through App Engine, rather than directly to storage.