A Python library for Juju
Source code: https://github.com/juju/python-libjuju
Bug reports: https://github.com/juju/python-libjuju/issues
Documentation: https://pythonlibjuju.readthedocs.io/en/latest/
Requirements
- Python 3.9/3.10
Design Notes
- Asynchronous - Uses asyncio and async/await features of Python
- Websocket-level bindings are programmatically generated (indirectly) from the Juju golang code, ensuring full api coverage
- Provides an OO layer which encapsulates much of the websocket api and provides familiar nouns and verbs (e.g. Model.deploy(), Application.add_unit(), etc.)
Installation
pip3 install juju
Quickstart
Here's a simple example that shows basic usage of the library. The example connects to the currently active Juju model, deploys a single unit of the ubuntu charm, then exits:
Note : Pylibjuju requires an already bootstrapped Juju controller to connect to.
#!/usr/bin/python3
import logging
import sys
from juju import jasyncio
from juju.model import Model
async def deploy():
# Create a Model instance. We need to connect our Model to a Juju api
# server before we can use it.
model = Model()
# Connect to the currently active Juju model
await model.connect()
try:
# Deploy a single unit of the ubuntu charm, using the latest revision
# from the stable channel of the Charm Store.
ubuntu_app = await model.deploy(
'ubuntu',
application_name='my-ubuntu',
)
if '--wait' in sys.argv:
# optionally block until the application is ready
await model.wait_for_idle(status = 'active')
finally:
# Disconnect from the api server and cleanup.
await model.disconnect()
def main():
logging.basicConfig(level=logging.INFO)
# If you want to see everything sent over the wire, set this to DEBUG.
ws_logger = logging.getLogger('websockets.protocol')
ws_logger.setLevel(logging.INFO)
# Run the deploy coroutine in an asyncio event loop, using a helper
# that abstracts loop creation and teardown.
jasyncio.run(deploy())
if __name__ == '__main__':
main()
More examples can be found in the docs, as well as in the examples/
directory of the source tree which can be run using tox
. For
example, to run examples/connect_current_model.py
, use:
tox -e example -- examples/connect_current_model.py
REPL
To experiment with the library in a REPL, launch python in asyncio mode
$ python3 -m asyncio
and then, to connect to the current model and fetch status:
>>> from juju.model import Model >>> model = Model() >>> await model.connect_current() >>> status = await model.get_status()
Versioning
The current Pylibjuju release policy tracks the Juju release cadence. In particular, whenever Juju makes a latest/stable release, pylibjuju pushes out a release with the same version in the following week. Newly generated schemas will be updated per Juju releases.