python-cellaserv3

Python3 client library for cellaserv3.

Features

See example usage in cellaserv/examples/.

Install

Install python-cellaserv3:

$ git clone --recurse-submodules https://github.com/evolutek/python-cellaserv3.git
$ python setup.py develop

Testing

Start the cellaserv3 server locally.
Run:

$ pytest

Codelab

First, follow the install instructions above.

Then, install and run cellaserv3:

$ go get github.com/evolutek/cellaserv3/cmd/...
$ cellaserv --logs-dir="/tmp"

Let's write our first service, date.py:

import asyncio
import time

from cellaserv.service import Service


class Date(Service):
    @Service.action
    async def time(self):
        return int(time.time())

async def main():
    date = Date()
    await date.done()


if __name__ == "__main__":
    asyncio.run(main())

Let's disect this file, we can skip the imports, there's nothing particular about them.

class Date(Service):

To define a new service, create a new class that inherits from the Service class. The name of the service on cellaserv will be the lowercase string of the class name, so here: date.

    @Service.action
    def time(self):
        return int(time.time())

Multiple things are important here. First @Service.action, this is a python decorator. This decorator marks the function as exported to cellaserv.

That's all, you can now run this file:

$ python date.py
INFO:cellaserv.service:Service running!

You can go on the cellaserv status page (http://localhost:4280) and you should see the date service in the Services column.

We can now query the time() action using cellaservctl:

$ cellaservctl request date.time
DEBU[2020-12-08T18:59:15+01:00] Sending request date[].time({})               module=client
1607450355

CellaservProxy

Example:

import asyncio

from cellaserv.proxy import CellaservProxy

async def main():
    cs = CellaservProxy()

    # Call the "time" method of the "date" service
    current_time = await cs.date.time()

    # Sending the "tirette" event. Notice that there is no "await" here because
    # sending is scheduled as a background coroutine
    cs("tirette")

    # Start two actions in parallel and wait for both to be completed
    await asyncio.wait([
      cs.robot.gotoxy(x=42, y=1337),
      cs.robot.setup_launcher(),
    ])

    # Start an action...
    task = cs.robot.gotoxy(x=1, y=2)
    # ... meanwhile, do something else ...
    await cs.robot.blink()
    # ... finally wait for the first task to finish
    await task

    # Start an action with a timeout
    try:
	await asyncio.wait_for(cs.robot.gotothetha(90), timeout=1)
    except asyncio.TimeoutError:
	print("Ooops")

if __name__ == "__main__":
    asyncio.run(main())

Authors

Rémi Audebert, Evolutek 2012-2020
Benoît Reitz, Evolutek 2013-2015
Adrien Schildknecht, Evolutek 2013-2015
Vincent Gatine, Evolutek 2014-2015
Corentin Vigourt, Evolutek 2014-2020