Libby

Libby: a tiny messaging library which uses Bamboo with pluggable transports (ZMQ or RabbitMQ)

Documentation

Full docs (installation, keywords, the Client library, the libby CLI, how to build a LibbyDaemon peer, the keygrabber, plus the generated API reference) are built with Sphinx + the Shibuya theme and published to GitHub Pages:

caltechopticalobservatories.github.io/libby

To build them locally:

tox -e docs
open docs/build/html/index.html

Quick start

git clone https://github.com/CaltechOpticalObservatories/libby
cd libby
python -m venv venv
source venv/bin/activate
pip install -e .

See the installation guide for full setup details, and the docs site above for everything else (keywords, the client library, the CLI, and writing a LibbyDaemon peer).

Finding peers

libby list <group>.<daemon> (and Client.peers) is how you find out which peers are up. It broadcasts a keys.list that every peer answers, so it works the same on both transports and needs nothing configured beyond the transport itself.

Discovery, in the sense of a peer table you can ask who is alive, is not implemented. It may be one day; until then use the broadcast above rather than these:

• Libby.peers_alive() returns {} and Libby.wait_for_peer() always fails, on either transport, because Protocol never instantiates a PeerTable.
• ZMQ runs bamboo's hello, but only toward peers already in the sender's address book, and nothing consumes it for liveness. A client learns nothing about a daemon that has not been told about the client, so Libby.knows_key() stays False in the usual one-sided setup.
• Libby.rabbitmq() does not start hello at all. The broker routes messages; it does not tell a peer who else is connected.

LibbyDaemon's discovery_enabled / on_hello control bamboo's hello, not the broadcast above.

Testing

python -m unittest discover -s tests

Most of tests/ needs no transport at all. tests/test_client_integration.py is the exception: it starts a real LibbyDaemon and exercises Client against it, once per transport. The ZMQ cases need no external service and always run; the RabbitMQ cases skip themselves if no broker is reachable at amqp://localhost.