Blossom uses nostr public / private keys for identities. Users are expected to sign authorization events to prove their identity when interacting with servers

Blossom is a specification for a set of HTTP endpoints that allow users to store blobs of data on publicly accessible servers

Blobs are packs of binary data addressed by their sha256 hash

BUDs or Blossom Upgrade Documents are short documents that outline an additional feature that a blossom server may implement.

• BUD-00: Blossom Upgrade Documents
• BUD-01: Server requirements and blob retrieval
• BUD-02: Blob upload and management
• BUD-03: User Server List
• BUD-04: Mirroring blobs
• BUD-05: Media optimization
• BUD-06: Upload requirements
• BUD-08: Nostr File Metadata Tags
• BUD-09: Blob Report
• BUD-10: Blob Search

Blossom Servers expose a few endpoints for managing blobs

• GET /<sha256> (optional file .ext) BUD-01
• HEAD /<sha256> (optional file .ext) BUD-01
• PUT /upload BUD-02
  • Authentication: Signed nostr event
  • Return a blob descriptor
• HEAD /upload BUD-06
• GET /list/<pubkey> BUD-02
  • Returns an array of blob descriptors
  • Authentication (optional): Signed nostr event
• DELETE /<sha256> BUD-02
  • Authentication: Signed nostr event
• PUT /mirror BUD-04
  • Authentication: Signed nostr event
• HEAD /media BUD-05
• PUT /media BUD-05
  • Authentication: Signed nostr event
• PUT /report BUD-09
• GET /search BUD-10

Public domain.