nitro-intercom

Publish/subscribe channels for Python services, backed by the same Rust core the Nitro framework uses internally.

Installation

pip install nitro-intercom

Python 3.13 or newer. The distribution is named nitro-intercom; the package it installs is nitro_intercom, which is what you import. The wheel carries the compiled core, so there is nothing to build. Redis is what it connects to, not something it installs.

Install this only if you are not running on Nitro. Nitro projects should import nitro.intercom, which reaches the same core in-process and takes its configuration from the project's settings object instead of a separate config surface.

Connecting

from nitro_intercom import Intercom

intercom = await Intercom.connect("redis://localhost:6379", prefix="myapp")

prefix keeps several applications apart on one server. capacity and expiry apply to queued channels.

Two ways to deliver

publish / subscribe is push delivery. A subscriber connected now gets the message immediately; one that is not never learns of it.

reached: int = await intercom.publish("room:42", {"event": "joined", "user": "ada"})

listener = await intercom.subscribe("room:42")
async for message in listener:
    print(message)
await listener.close()

send / receive is a bounded queue. A message waits until it is read or the channel expires, and the oldest is discarded once the channel is full.

await intercom.send("jobs", {"task": "resize", "id": 7})

message = await intercom.receive("jobs")        # None when empty

reader = await intercom.reader("jobs")
message = await reader.receive(timeout=30)      # waits; 0 waits indefinitely

Groups

A group is a named set of channels, so a message can be addressed to "everyone in room 42" without the sender knowing who that is.

await intercom.group_add("room:42", channel)
await intercom.group_discard("room:42", channel)

members: list[str] = await intercom.group_channels("room:42")

await intercom.group_publish("room:42", {"event": "started"})   # to those listening
await intercom.group_send("room:42", {"event": "started"})      # queued for each

What crosses the wire

None, bool, int, float, str, bytes, list, tuple and dict, encoded as MessagePack so a service written in another language can read them. Tuples arrive as lists. Anything else is refused rather than coerced, because guessing would mean the receiver gets something the sender did not mean to send.

License

Licensed under either of Apache License, Version 2.0 or the MIT license, at your option.