ircio 1.2.0

Async IRC library for Python 3.14+

ircio

An asynchronous IRC client library for Python 3.14+, built on top of asyncio.

Features

• Fully async — all I/O is non-blocking via asyncio.StreamReader/StreamWriter
• IRCv3 message tags — parsed and serialised transparently
• TLS — plain ssl=True for system CA verification, or pass a custom ssl.SSLContext for client certificates and private networks
• SASL authentication
  • PLAIN — username and password (RFC 4616)
  • EXTERNAL — identity delegated to the TLS certificate
  • ECDSA-NIST256P-CHALLENGE — challenge–response using an ECDSA key on the NIST P-256 curve (used by Libera.Chat and other networks)
• Event dispatcher — register async handlers per command, with wildcard ("*") support
• Structured concurrency — handlers are dispatched via asyncio.TaskGroup

Requirements

• Python ≥ 3.14
• uv (recommended) or any PEP 517-compatible build tool

Optional, for ECDSA-NIST256P-CHALLENGE:

pip install "ircio[ecdsa]"

Quick start

import asyncio
from ircio import Client

client = Client(
    "irc.libera.chat",
    6697,
    nick="mybot",
    user="mybot",
    realname="My Bot",
    ssl=True,
)

@client.on("PRIVMSG")
async def on_privmsg(msg):
    target = msg.params[0]
    text   = msg.params[1]
    print(f"[{target}] {msg.prefix}: {text}")

async def main():
    await client.connect()
    await client.join("#python")
    await client.run()

asyncio.run(main())

SASL authentication

PLAIN

from ircio import Client, SASLPlain

client = Client(
    "irc.libera.chat", 6697,
    nick="mybot", user="mybot", realname="My Bot",
    ssl=True,
    sasl=SASLPlain("mybot", "s3cr3t"),
)

ECDSA-NIST256P-CHALLENGE

Register your public key with NickServ, then authenticate using the corresponding private key:

from ircio import Client, SASLEcdsaNist256pChallenge

sasl = SASLEcdsaNist256pChallenge.from_pem_file("mybot", "~/.irc/key.pem")

client = Client(
    "irc.libera.chat", 6697,
    nick="mybot", user="mybot", realname="My Bot",
    ssl=True,
    sasl=sasl,
)

Generate a key with OpenSSL:

openssl genpkey -algorithm EC -pkeyopt ec_paramgen_curve:P-256 -out ~/.irc/key.pem
openssl pkey -in ~/.irc/key.pem -pubout

Provide the public key to NickServ: /msg NickServ SET PUBKEY <base64-pubkey>.

EXTERNAL (client certificate)

import ssl
from ircio import Client, SASLExternal

ctx = ssl.create_default_context()
ctx.load_cert_chain("cert.pem", "key.pem")

client = Client(
    "irc.libera.chat", 6697,
    nick="mybot", user="mybot", realname="My Bot",
    ssl=ctx,
    sasl=SASLExternal(),
)

Low-level API

Connection and Dispatcher are exposed for use cases that require finer control:

from ircio import Connection, Dispatcher, Message

async def main():
    async with Connection("irc.libera.chat", 6697, ssl=True) as conn:
        await conn.send(Message("NICK", ["mybot"]))
        await conn.send(Message("USER", ["mybot", "0", "*", "My Bot"]))
        while True:
            msg = await conn.readline()
            print(msg)

Development

uv sync
uv run pytest
uv run ruff check src/ tests/
uv run ruff format src/ tests/

Pre-commit hooks (ruff linter + formatter) are installed automatically on first commit after:

uv run pre-commit install

Licence

MIT — see LICENSE.