blossoML

blossoML is yet another Blossom server implementation written in OCaml.

Endpoints

• GET /<sha256> - Get blob (BUD-01)
• HEAD /<sha256> - Has blob (BUD-01)
• PUT /upload - Upload blob (BUD-02)
• HEAD /upload - Upload requirements (BUD-06)
• PUT /mirror - Mirror blob (BUD-04)
• DELETE /<sha256> - Delete blob (BUD-12)
• GET /list/<pubkey> - List blobs (BUD-12) (unrecommended)
• HEAD /media - Media optimization info (BUD-05)
• PUT /media - Media optimization (BUD-05)
• PUT /report - Blob report (BUD-09)

Other BUDs

• Nostr Authorization (kind:24242) (BUD-11)
• Nostr File Metadata Tags (nip94 in blob descriptor) (BUD-08)
• Payment Required (402 + X-Cashu / X-Lightning) (BUD-07)

BUD-03 (User Server List) and BUD-10 (Blossom URI Schema) are client-side specifications and do not apply to server implementations.

Technology Stack

The OCaml libraries that blossoML depends on:

• HTTP server: Piaf
• Concurrent I/O: Eio
• Database: SQLite via Caqti
• Hashing: Digestif for SHA256
• MIME detection: Conan

Quick Start

Prerequisites

• OCaml 5.x
• opam
• libsecp256k1

Installation

# Install dependencies
opam install . --deps-only

# Build
dune build

# Run
dune exec blossoML -- --port 8080

Command Line Options

--host      Host to bind to (default: localhost)
            Use "0.0.0.0" for external access
--port      Port to listen on
--cert      Path to SSL certificate (optional)
--key       Path to SSL private key (optional)
--base-url  Base URL for blob URLs in responses
            (e.g., https://example.com:8080)

Examples

# Local development
dune exec blossoML -- --host localhost --port 8080

How to Run Tests

dune test

Acknowledgements

This project was inspired by Piaf and Waq.

License

MIT.