$ pip install bottle-api

json_endpoint decorator will make a function to JSON WebAPI endpoint. decorated function will return bottle.HTTPResponse.

see this sample web app:

#!python
from bottleapi import WebApiError
from bottleapi.jsonapi import json_endpoint
from bottle import Bottle, request

app = Bottle()

@json_endpoint
def devide():
    a = int(request.params['a'])
    b = int(request.params['b'])
    if b == 0:
        raise WebApiError('b cannot be zero', status=400)

    result = a / b
    return dict(value=result)

app.route('/devide', ['GET'], devide)

if you access /devide?a=1&b=1, it will return 200 OK response with body:

{"status": "ok", "result": {"value": 1}}

with Content-Type application/json

but when you access devide?a=1&b=0, you will get 400 BAD REQUEST response with body:

{"status": "error", "message": "b cannot be zero", "result": null}

If you want to use JSONP, you can specify callback function name with parameter(j by default) So accessing /devide?a=4&b=2&j=my_callback will result:

my_callback({"status": "ok", "result": {"value": 2}});

If you dont like parameter or result data format, You can define your own formatters(success/error). See jsonapi.py for customized formatter example.