argparseweb 0.1.3

Automatic exposure of argparse-compatible scripts as a web interface

[![Version Status][v-image]][pypi-url]

# README #

This web.py based simple module allows you to automatically set up a simple HTTP web server out of advanced `argparse.ArgumentParser` objects and similar (`argh.ArgumentParser`) ones.
Using this on top of argh lets you automatically generate web user interface out of simple functions defined in your application.
This package was made for getting your personal command line scripts to the next stage - internal shared utilities.

### How do I set up? ###

For a production like setup you'll need:

1. make your main script expose an application global object by calling webui.Webui.wsgi() method

2. modify `index.wsgi` to fit your application (trivial configuration, import aforementioned application)

3. set up a wsgi supporting apache (or any other) server

For debugging like setup you'll need (but since it's used for internal tools, this might also be fine):

1. replace methods like `argparse.ArgumentParser.parse_args()` or `argh.dispatch()` with `webui.Webui.getone()` or `webui.Webui.dispatch()` respectively.

`dispatch()` will instantiate a web service and call dispatch methods (either provided by the user - you - or dispatch methods of supporting argument parsers like `argh`)

`get()` and `getone()` wrap the `dispatch()` method and yield results as they are submitted in the web form, providing an interface that resembles the `parse_args()` method.

### Dependencies ###

`argparseweb` requires `web.py` to be available. You can install it (check for the latest version) with: `pip install web.py`

### Basic examples ###
This example will set up an http server, get one valid input, tear the http server down, print a welcoming message to stdout and exit:
```python
import argparse
from argparseweb import *

def main():
parser = argparse.ArgumentParser()

parser.add_argument("name", default="Anonymous")

# previously opts = parser.parse_args()
opts = webui.Webui(parser).getone()
print("Hello {name},\nthis is a simple example.".format(name=opts.name))

if __name__ == "__main__":
main()
```

This example will also run until stopped, printing a welcoming message for every valid input:
```python
import argparse
from argparseweb import *

def main():
parser = argparse.ArgumentParser()

parser.add_argument("name", default="Anonymous")

# previously opts = parser.parse_args()
for opts in webui.Webui(parser).get():
print("Hello {name},\nthis is a simple example.".format(name=opts.name))

if __name__ == "__main__":
main()
```

This example will print the welcoming message in the http response, sending it back to the user:
```python
import argparse
from argparseweb import *

def welcome(opts):
print("Hello {name},\nthis is a simple example.".format(name=opts.name))

def main():
parser = argparse.ArgumentParser()

parser.add_argument("name", default="Anonymous")

# previously opts = parser.parse_args()
webui.Webui(parser).dispatch(welcome, parsed=True)

if __name__ == "__main__":
main()
```

### A more complicated example ###

This snippet includes three modes of operation for the webui utility:

1. first and simplest: dispatch methods using argh's automatic function to command line parser facilities, this is completely unrelated to webui and that way you won't lose existing command line usage ability.

2. getting `--webui` as the first command line argument, sets up a development web server (defaults to *:8080) and is ready to use.

3. exposing an `application` global object that supports the wsgi interface. once you point a browser with correct wsgi configuration (was a bit of a pain for me first time) it'll work like magic :)

myapp.py:
```python
import argparse
from argparseweb import *

def get_parser():
"""Generate generic argument parser"""
cmd_parser = argh.ArghParser()
cmd_parser.add_commands([...])

return cmd_parser

def main_1():
# k. get the parser as usual
cmd_parser = get_parser()

# last chance to use webui, if --webui is passed as first command line argument
# remove it as let webui handle the rest
if sys.argv[1] == '--webui':
sys.argv.remove('--webui')
webui.Webui(cmd_parser).dispatch() # second mode of operation - development/fast setup
else:
# dispatch either webui or argh
cmd_parser.dispatch() # first mode of operation - regular command line

def main_2():
parser = argparse.ArgumentParser()

# TODO: fill argparse

# opts = parser.parse_args()
opts = webui.Webui(parser).getone()

# TODO: use opts as you would with any ArgumentParser generated namespace,
# opts is really a namespace object directly created by parser, and webui only compiled an argument sequence
# based on the filled form, passed into parser.parse_args() and back to you

def wsgi():
global application

# create a webui application using the command line argument parser object
# and make it's wsgi function the global `application` parameter as required by wsgi
cmd_parser = get_parser()
application = webui.Webui(cmd_parser).wsgi() # third mode of operation - production wsgi application

if __name__ == "__main__":
# script initialized as main, lets do our trick
main()
else:
# if script wasn't initialized as main script, we're probably running
# in wsgi mode
wsgi()
```
index.wsgi:
```python
# TODO: replace with your application path
# i found now way to get it automatically in wsgi :/
APP_DIR = '/var/www/myapp'

import sys, os
sys.path.insert(0, APP_DIR)
os.chdir(APP_DIR)

from myapp import application

```

More examples are at `test.py`

### known issues ###

* right now vary-length arguments (nargs='?', nargs='*', nargs='+') are limited to one argument because i didn't write the HTML required for that. i'm considering multiple text inputs or textarea with line separation, input (and code) are most welcome.

Done:

* some code reordering is needed (split template to another file - it's grown quite big, handle action parameters better - shouldn't pass everything as html attributes although it's comfortable)
* smoother integration into existing code.

[v-image]: https://img.shields.io/pypi/v/argparseweb.svg
[dm-image]: https://img.shields.io/pypi/dm/argparseweb.svg

[pypi-url]: https://pypi.python.org/pypi/argparseweb/