Security
Signed URL / Valet Key
A Signed URL is a temporary, secure link that allows a client to upload or download files directly from cloud storage, bypassing the app server.
Diagram
1. Client ── Request upload ──▶ [App Server]
▲ │ 2. Returns Signed URL
│ ▼
└────── 3. Upload file directly ──▶ [Cloud Storage (S3)]In Depth
A Signed URL (also known as the Valet Key pattern) is a URL that contains cryptographic query parameters (signature, expiration, and permissions) granting temporary access to a specific file in cloud storage.
Related Terms