aiotraversal

This is small web framework, around aiohttp_traversal.

Hello World

app.py:

import asyncio

from aiohttp.web import Response

from aiohttp_traversal.ext.resources import Root
from aiohttp_traversal.ext.views import View, RESTView

from aiotraversal import Application
from aiotraversal.cmd import run


class HelloView(View):
    @asyncio.coroutine
    def __call__(self):
        return Response(text="Hello World!\n")


class HelloJSON(RESTView):
    methods = {'get'}

    @asyncio.coroutine
    def get(self):
        return dict(text="Hello World!")


def main():
    loop = asyncio.get_event_loop()

    app = Application()  # create main application instance

    with app.configure(loop=loop) as config:  # start configure process
        config.include('aiotraversal.cmd')  # include module for command-line parsing
        config.include('aiotraversal.serve')  # include module for start serving
        config.bind_view(Root, HelloView)  # add view for '/'
        config.bind_view(Root, HelloJSON, 'json')  # add view for '/json'

    run(app, loop=loop)  # start application


if __name__ == '__main__':
    main()

$ python app.py serve

$ curl http://localhost:8080
Hello World!
$ curl http://localhost:8080/json
{"text": "Hello World!"}

Content

Command-line interface

Module aiotraversal.cmd makes if easy to write command-line interfaces for you application.

Parser

After config.include('aiotraversal.cmd'), you can use these objects:

• config['cmd']['parser']: ArgumentParser instance;
• config['cmd']['subparsers']: subparsers for create commands, the main tool for extend console application;

After configure process finished:

• app['cmd']['args']: Namespace instance from config['cmd']['parser'].parse_args();
• app['cmd']['run_func']: function for Function run;

Add commands

Something like this:

import asyncio

from aiotraversal import Application
from aiotraversal.cmd import run

def cmd_func(app, loop):
    print('cmd_func is called!')


def main():
    loop = asyncio.get_event_loop()
    app = Application()

    with app.configure(loop=loop) as config:
        config.include('aiotraversal.cmd')  # include

        subparsers = config['cmd']['subparsers']
        parser_test = subparsers.add_parser('test_command', help="Test")  # create subparser
        parser_test.set_defaults(func=cmd_func)  # add function for start
        # ... extend subpaser with `parser_test.add_argument`

    run(app, loop)  # in this place cmd_func is called

Now, if run your application with argument test_command (e.g. my_cmd test_command), “cmd_func is called!” printed.

Default key func of subparser, is magic for bind functions to commands. It is called from the Function run with two arguments: app and loop.

ArgumentParser

ArgumentParser is modified for grouping subcommand arguments.

StackOverflow with this solution.

Function run

After configure process, you must run aiotraversal.cmd.run. It run app['cmd']['run_func'], finish application and close loop.

Serve helper

For add command serving, include aiotraversal.serve:

import asyncio

from aiotraversal import Application
from aiotraversal.cmd import run

def main():
    loop = asyncio.get_event_loop()
    app = Application()  # create main application instance

    with app.configure(loop=loop) as config:
        config.include('aiotraversal.cmd')
        config.include('aiotraversal.serve')  # include module for serving
        # some other includes

    run(app, loop=loop)  # start application

$ python app.py serve --help
usage: app.py serve [-h] [--listen HOST:PORT] [--static DIR]

optional arguments:
  -h, --help          show this help message and exit
  --listen HOST:PORT  host and port for listen (default 'localhost:8080')
  --static DIR        Serve static files

Objects

• config['cmd']['parser_serve']: subparser for serve command;

Arguments

serve command have some arguments.

--listen

Adderss for listen. Default localhost:8080.

Host or port may be not specified. E.g.:

• --listen 0.0.0.0 equal --listen 0.0.0.0:8080
• --listen :8082 equal --listen localhost:8082

--static

Serve static directory. Specified directory is can be found in GET /static/.

Warning

Do not use in production! Access to files is synchronous!

Settings

If aiotraversal.settings is included, you can use settings for setup default values.

For example:

[serve]
listen = "10.0.0.15:8080"
static = "/srv/static"

Settings

Just include Settings.

Settings uses zini.

All keys in section named “app”, set to config['settings']. Other sections set to config['settings'][section_name].

For example:

[app]
author = "ZZZ"

[serve]
listen = ":6543"

assert app['settings']['author'] == 'ZZZ'
assert app['settings']['serve']['listen'] == ':6543'

Objects

• config['settings_ini']: instance of Zini <https://github.com/zzzsochi/zini>;
• config['settings']['file']: path to file with settings;

Arguments

aiotraversal.cmd module is not required.

--settings

Path to ini-file with setings. This is setup config['settings']['file'].