NostrTools for Elixir

NostrTools implements the core Nostr protocol primitives and other useful functions needed to develop a variety of different Nostr applications in Elixir.

NostrTools deals with events, filters and protocol messages and provides helper functions to manage these. It does not try to solve application specific issues such as event storage or websocket connections.

There is a lot of NIPs functionality that still needs to be implemented. If you use this library and expand its functionality, please share the changes.

Credit to sgiath for the crypto library and the initial implementation.

Installation

The package can be installed by adding nostr_tools to your list of dependencies in mix.exs:

def deps do
  [{:nostr_tools, git: "https://github.com/neoamos/nostr_tools_ex"}]
end

The package is not on hex.pm since the crypto library used is not on hex.pm.

During compilation, the crypto library needs to compile some C code. Please refer to the crypto library documentation if you have issues.

Examples

Generate keys

iex> seckey = NostrTools.Crypto.generate_seckey()
iex> pubkey = NostrTools.Crypto.pubkey(seckey)

Create a new Event

iex> seckey = NostrTools.Crypto.generate_seckey()
iex> {:ok, event} = NostrTools.Event.create("content", seckey, 1, [])

Encode and decode an event to json

iex> seckey = NostrTools.Crypto.generate_seckey()
iex> {:ok, event} = NostrTools.Event.create("content", seckey, 1, [])
iex> {:ok, json_event} = Jason.encode(event)
iex> {:ok, decoded_event} = NostrTools.Event.create(Jason.decode!(json_event))
iex> event == decoded_event
true

Verify an event

iex> seckey = NostrTools.Crypto.generate_seckey()
iex> {:ok, event} = NostrTools.Event.create("content", seckey, 1, [])
iex> NostrTools.Event.valid?(event)
true

iex> seckey = NostrTools.Crypto.generate_seckey()
iex> {:ok, event} = NostrTools.Event.create("content", seckey, 1, [])
iex> NostrTools.Event.valid?(%NostrTools.Event{event | content: "wrong content"})
false

Generate a request for events

iex> filter = %NostrTools.Filter{since: 1673380970}
iex> Jason.encode!(NostrTools.Message.req("sub id", filter))
~s<[\"REQ\",\"sub id\",{\"since\":1673380970}]>