Blossom Upgrade Documents (mirror)

Defines the language every other BUD is written in, and what a blob is: raw binary data addressed by the sha256 hash of that data.

How a server charges for an endpoint: a 402 response carrying the payment terms, for uploads, downloads or media processing.

Defines HEAD /upload, a preflight request telling a client whether an upload would be accepted before it sends the bytes.

Defines PUT /upload and the blob descriptor, the JSON object describing a stored blob: its url, hash, size, mime type and upload time.

The base every Blossom server implements: the CORS headers, the error reporting, and the GET and HEAD endpoints that serve a blob by its hash.

Defines PUT /media, where a server transcodes and optimises what it is given rather than storing the bytes untouched.

Defines PUT /mirror, which asks a server to fetch a blob from a URL itself instead of having the client upload the same bytes twice.

Defines the management endpoints: listing what a pubkey uploaded, and deleting a blob by its hash.

Defines the kind 24242 event a user signs to prove to a server that they allowed an application to act on their behalf.

Defines the blossom: URI, which carries a blob hash, its extension, and hints about the servers where it can be found.

Defines PUT /report, where a client submits a signed NIP-56 report naming the blobs it objects to.

Defines kind 10063, the replaceable event where a user lists the Blossom servers holding their blobs, most trusted first.

How a server returns NIP-94 file metadata alongside a blob descriptor, so a client can publish the file without recomputing it.