falconjsonio 1.0.4

JSON-Schema input and output for Falcon

Validate HTTP request and response body by defining acceptable values with JSON schema. For use with the Falcon web framework.

Test status

Usage overview

Define your request body schema, and your endpoint is only called if the request matches your specification. Otherwise, an error is returned to the caller.

Define your response body schema, and your response is validated before returning to the sender. A response that does not match the specification will return a 500 error instead.

Retrieve your request JSON using req.context[‘doc’].

Set your JSON response in req.context[‘result’].

Using the middleware

Enabled the middleware:

app = falcon.API(
    middleware=[
        falconjsonio.middleware.RequireJSON(),
        falconjsonio.middleware.JSONTranslator(),
    ],
)

Define your requirements:

from falconjsonio.schema import request_schema, response_schema

people_post_request_schema = {
    'type':       'object',
    'properties': {
        'title':  {'type': 'string'},
        'name':   {'type': 'string'},
        'dob':    {'type': 'date-time'},
        'email':  {'type': 'email'},
    },
    'required': ['name', 'dob'],
}
people_post_response_schema = {
    'oneOf': [
        {
            'type':       'object',
            'properties': {
                'href': {'type': uri'},
            },
            'required': ['uri'],
        },
        {
            'type':       'object',
            'properties': {
                'error': {'type': 'string'},
            },
            'required': ['error'],
        },
    ],
}

# ...

class People(object):
    @response_schema(people_get_response_schema)
    def on_get(self, req, resp):
        # Put your JSON response here:
        req.context['result'] = {'some': 'json'}

    @request_schema(people_post_request_schema)
    @response_schema(people_post_response_schema)
    def on_post(self, req, resp):
        # JSON request supplied here:
        form = req.context['doc']
        # Put your JSON response here:
        req.context['result'] = {'some': 'json'}

Hook the endpoint in, of course:

app.add_route('/people', People())

If your methods are inherited from a parent class, you can apply the decorator to the resource class instead, and pass the method name to the decorator:

class People(object):
    def on_get(self, req, resp):
        # Put your JSON response here:
        req.context['result'] = {'some': 'json'}

    def on_post(self, req, resp):
        # JSON request supplied here:
        form = req.context['doc']
        # Put your JSON response here:
        req.context['result'] = {'some': 'json'}

@response_schema(schema=people_get_response_schema, method_name='on_get')
@request_schema(schema=people_post_request_schema, method_name='on_post')
@response_schema(schema=people_post_response_schema, method_name='on_post')
class ChildPeople(People):
    pass

This is especially useful when you have a parent class with all the smarts, and your child classes merely declare a few settings for the parent class (e.g. falcon-autocrud)

Quick start for contributing

virtualenv -p `which python3` virtualenv
source virtualenv/bin/activate
pip install -r requirements.txt
pip install -r dev_requirements.txt
nosetests