aio.app 0.0.5

Aio application runner

Application runner for the aio asyncio framework

Build status

Installation

Install with:

pip install aio.app

Configuration

By default the aio command will look for the following configuration files

• aio.conf

• etc/aio.conf

• /etc/aio.conf

Once it has found a config file it uses that one

A custom configuration file can also be provide with “-c”, eg

aio -c custom.conf run

A basic configuration with the 2 provided commands, test and run is

[aio:commands]
run = aio.app.cmd.cmd_run
test = aio.app.testing.cmd.cmd_test

aio run

With the above configuration the app server can be run with

aio run

On startup the app server sets up the following

• Configuration - system-wide read-only configuration

• Modules - known modules

• Schedulers - functions called at set times

• Servers - listening on tcp/udp or other type of socket

• Signals - functions called in response to events

Configuration

The system configuration is importable from aio.app

from aio.app import config

Modules

You can list any modules that should be imported at runtime in the configuration

[aio]
modules = aio.app
        aio.signals

The system modules can be accessed from aio.app

from aio.app import modules

Schedulers

Any sections in the configuration that start with schedule: will create a scheduler.

Specify the frequency and the function to call. The function should be a co-routine.

[schedule:example]
every = 2
func = my.scheduler.example_scheduler

The scheduler function takes 1 argument the name of the scheduler

@asyncio.coroutine
def example_scheduler(name):
    # do something
    pass

Servers

Any sections in the configuration that start with server: will create a server

The server requires either a factory or a protocol to start

Protocol configuration example:

[server:example]
protocol = my.example.ServerProtocol
address = 127.0.0.1
port = 8888

Protocol example code:

class ServerProtocol(asyncio.Protocol):

    def connection_made(self, transport):
        self.transport = transport

    def data_received(self, data):
        # do stuff
        self.transport.close()

If you need further control over how the protocol is created and attached you can specify a factory method

Factory configuration example:

[server:example]
factory = my.example.server_factory
address = 127.0.0.1
port = 8080

Factory code example:

@asyncio.coroutine
def server_factory(name, protocol, address, port):
    loop = asyncio.get_event_loop()
    return (
        yield from loop.create_server(
           ServerProtocol, address, port))

Signals

Any section in the configuration that starts with listen: will subscribe listed functions to given events

An example listen configuration section

[listen:example]
example-signal = my.example.listener

And an example listener function

@asyncio.coroutine
def listener(signal, message):
    print(message)

yield from app.signals.emit(
    'example-signal', "BOOM!")

You can add multiple subscriptions within the section

[listen:example]
example-signal = my.example.listener
example-signal-2 = my.example.listener2

You can also subscribe multiple functions to a signal

[listen:example]
example-signal = my.example.listener
               my.example.listener2

aio test

Include the test command in your config

[aio]
modules = aio.app
         aio.signals

[aio:commands]
test = aio.app.testing.cmd.cmd_test

The aio test runner will then test all modules listed in the aio config section

aio test

You can also specify a module

aio test aio.app

Dependencies

aio.app depends on the following packages

• aio.core

• aio.signals

• aio.config

Related software

• aio.http

• aio.web

The aio command runner

The aio command can be run with any commands listed in the [aio:commands] section of its configuration

Initially aio.app does not have any config, signals, modules or servers

>>> import aio.app

>>> print(aio.app.config)
None

>>> print(aio.app.signals)
None

>>> print(aio.app.modules)
()

>>> print(aio.app.servers)
{}

Lets start the app runner in a test loop with a minimal configuration

>>> config = """
... [aio:commands]
... run: aio.app.cmd.cmd_run
... """

>>> from aio.app.runner import runner

>>> def run_app():
...     yield from runner(['run'], config_string=config)
...     print(aio.app.signals)
...     print(aio.app.config)

>>> from aio.testing import aiotest
>>> aiotest(run_app)()
<aio.signals.Signals object ...>
<configparser.ConfigParser ...>

Clear the app

We can clear the app vars

>>> aio.app.clear()

>>> print(aio.app.signals)
None

>>> print(aio.app.config)
None

>>> print(aio.app.modules)
()

>>> print(aio.app.servers)
{}

Adding a signal listener

Lets create a test listener and make it importable

>>> def test_listener(signal, message):
...     print("Listener received: %s" % message)

The listener needs to be a coroutine

>>> import asyncio
>>> aio.app.tests._test_listener = asyncio.coroutine(test_listener)

>>> config = """
... [aio:commands]
... run: aio.app.cmd.cmd_run
...
... [listen:testlistener]
... test-signal: aio.app.tests._test_listener
... """

>>> def run_app_test_emit(msg):
...     yield from runner(['run'], config_string=config)
...     yield from aio.app.signals.emit('test-signal', msg)

>>> aiotest(run_app_test_emit)('BOOM!')
Listener received: BOOM!

>>> aio.app.clear()

Adding app modules

We can make the app runner aware of any modules that we want to include

>>> config = """
... [aio]
... modules = aio.app
...          aio.core
...
... [aio:commands]
... run: aio.app.cmd.cmd_run
... """

>>> def run_app_print_modules():
...     yield from runner(['run'], config_string=config)
...     print(aio.app.modules)

>>> aiotest(run_app_print_modules)()
[<module 'aio.app' from ...>, <module 'aio.core' from ...>]

>>> aio.app.clear()

Running a scheduler

Lets create a scheduler function. It needs to be a coroutine

>>> def test_scheduler(name):
...      print('HIT: %s' % name)

>>> aio.app.tests._test_scheduler = asyncio.coroutine(test_scheduler)

We need to use a aiofuturetest to wait for the scheduled events to occur

>>> from aio.testing import aiofuturetest

>>> config = """
... [aio:commands]
... run: aio.app.cmd.cmd_run
...
... [schedule:test-scheduler]
... every: 2
... func: aio.app.tests._test_scheduler
... """

>>> def run_app_scheduler():
...     yield from runner(['run'], config_string=config)

Running the test for 5 seconds we get 3 hits

>>> aiofuturetest(run_app_scheduler, timeout=5)()
HIT: test-scheduler
HIT: test-scheduler
HIT: test-scheduler

>>> aio.app.clear()
>>> del aio.app.tests._test_scheduler

Running a server

Lets run an addition server

>>> class AdditionServerProtocol(asyncio.Protocol):
...
...     def connection_made(self, transport):
...         self.transport = transport
...
...     def data_received(self, data):
...         self.transport.write(
...             str(
...                 sum([
...                     int(x.strip()) for x in
...         data.decode("utf-8").split("+")])).encode())
...         self.transport.close()

>>> def addition_server(name, protocol, address, port):
...     loop = asyncio.get_event_loop()
...     return (
...         yield from loop.create_server(
...            AdditionServerProtocol,
...            address, port))

>>> aio.app.tests._test_addition_server = asyncio.coroutine(addition_server)

>>> config = """
... [aio:commands]
... run: aio.app.cmd.cmd_run
...
... [server:additiontest]
... factory: aio.app.tests._test_addition_server
... address: 127.0.0.1
... port: 8888
... """

>>> def run_app_addition(addition):
...     yield from runner(['run'], config_string=config)
...
...     @asyncio.coroutine
...     def call_addition_server():
...          reader, writer = yield from asyncio.open_connection(
...              '127.0.0.1', 8888)
...          writer.write(addition.encode())
...          yield from writer.drain()
...
...          result = yield from reader.read()
...          print(int(result))
...
...     return call_addition_server

>>> aiofuturetest(run_app_addition, timeout=5)('2 + 2 + 3')
7