Add aiohttp.web command-line interface to serve apps

aiohttp/web.py

@@ -17,7 +17,6 @@
 from .web_urldispatcher import *  # noqa
 from .web_ws import *  # noqa
 
-
 __all__ = (web_reqrep.__all__ +
            web_exceptions.__all__ +
            web_urldispatcher.__all__ +
@@ -322,3 +321,7 @@ def run_app(app, *, host='0.0.0.0', port=None,
         loop.run_until_complete(handler.finish_connections(shutdown_timeout))
         loop.run_until_complete(app.cleanup())
     loop.close()
+
+if __name__ == "__main__":
+    from .web_main import main
+    main()

aiohttp/web_main.py

@@ -0,0 +1,43 @@
+from .web import run_app
+from argparse import ArgumentParser
+from importlib import import_module
+
+
+def main():
+    arg_parser = ArgumentParser(
+        description="aiohttp.web TCP/IP Application server",
+        prog="aiohttp.web"
+    )
+    arg_parser.add_argument(
+        "entry_func",
+        help=("Callable returning the `aiohttp.web.Application` instance to "
+              "run. Should be specified in the Python import syntax, "
+              "e.g. 'package.module.function')"),
+        metavar="entry-func"
+    )
+    arg_parser.add_argument(
+        "-n", "--hostname",
+        help="TCP/IP hostname to serve on (default: %(default)r)",
+        default="localhost"
+    )
+    arg_parser.add_argument(
+        "-p", "--port",
+        help="TCP/IP port to serve on (default: %(default)r)",
+        type=int,
+        default="8080"
+    )
+    args, extra_args = arg_parser.parse_known_args()
+
+    # Import logic
+    mod_str, _, func_str = args.entry_func.rpartition(".")
+    try:
+        module = import_module(mod_str)
+        func = getattr(module, func_str)
+    except (ImportError, ValueError) as e:
+        arg_parser.error(e)
+    except AttributeError as e:
+        arg_parser.error(e)
+
+    app = func(extra_args)
+    run_app(app, host=args.hostname, port=args.port)
+    arg_parser.exit(message="Stopped\n")

docs/web.rst

@@ -34,13 +34,34 @@ particular *HTTP method* and *path*::
 
 After that, run the application by :func:`run_app` call::
 
-   run_app(app)
+   web.run_app(app)
 
 That's it. Now, head over to ``http://localhost:8080/`` to see the results.
 
-.. seealso:: :ref:`aiohttp-web-graceful-shutdown` section
-             explains what :func:`run_app` does and how implement
-             complex server initialization/finalization from scratch.
+.. seealso::
+
+   :ref:`aiohttp-web-graceful-shutdown` section explains what :func:`run_app`
+   does and how to implement complex server initialization/finalization
+   from scratch.
+
+
+.. _aiohttp-web-cli:
+
+Command Line Interface (CLI)
+----------------------------
+:mod:`aiohttp.web` implements a basic CLI for quickly serving an
+:class:`Application` in *development* over TCP/IP::
+
+    $ python -m aiohttp.web -n localhost -p 8080 package.module.init_func
+
+``package.module.init_func`` should be an importable :term:`callable` that
+accepts a list of any non-parsed command-line arguments and returns an
+:class:`Application` instance after setting it up::
+
+    def init_function(args):
+        app = web.Application()
+        app.router.add_route("GET", "/", index_handler)
+        return app
 
 
 .. _aiohttp-web-handler:
@@ -858,8 +879,6 @@ finalizing.  It's pretty close to :func:`run_app` utility function::
    loop.close()
 
 
-
-
 CORS support
 ------------
 

examples/web_app.py

@@ -0,0 +1,20 @@
+"""
+Example for running Application using the `aiohttp.web` CLI.
+
+Run this app using::
+
+    $ python -m aiohttp.web web_app.init
+"""
+
+from aiohttp.web import Application, Response
+
+
+def hello_world(req):
+    return Response(text="Hello World")
+
+
+def init(args):
+    app = Application()
+    app.router.add_route('GET', '/', hello_world)
+
+    return app