Klein json api authentication class

auth.py

from functools import wraps
import json
from klein import Klein

class JsonApi(object):
    """
    Reusable class for composing a JSON API easily with minimal
    repeated code.
    """

    def __init__(self, app=None, secret='twisted'):
        self.app = app if app else Klein()
        self.secret = secret

    def toJSON(self, data):
        """
        Serialize data to JSON
        """
        return json.dumps(data)

    def defaultMiddleware(self, f):
        """
        Middleware to set application/json as default header for
        all responses.
        """
        @wraps(f)
        def deco(*args, **kwargs):
            request = args[0]
            request.setHeader('Content-Type', 'application/json')
            return self.toJSON(f(*args, **kwargs))

        return deco

    def authenticate(self, f):
        """
        Middleware api-key authentication
        """
        @wraps(f)
        def deco(*args, **kwargs):
            request = args[0]
            apiKey = request.getHeader('Authorization')
            if not apiKey or apiKey != self.secret:
                request.setResponseCode(401)
                body = {
                    'scope': 'private',
                    'message': 'Sorry, valid credentials required to access content'}
                return body
            return f(*args, **kwargs)

        return deco

    def route(self, url, *args, **kwargs):
        """
        Extend the route functionality
        """
        def deco(f):
            restricted = kwargs.pop('restricted', False)
            if restricted:
                f = self.authenticate(f)
            f = self.defaultMiddleware(f)
            self.app.route(url, *args, **kwargs)(f)
        return deco


def main():
    main_app = Klein()
    json_api = JsonApi(app=main_app, secret='tw15t3d')

    @main_app.route('/')
    def home(request):
        return 'Hello World'

    @json_api.route('/jsonify', methods=['GET'])
    def jsonify(request):
        return {'foo': 'bar'}

    @json_api.route('/admin', restricted=True)
    def admin(request):
        return {'scope': 'private', 'message': 'Access restricted content'}

    @json_api.route('/admin/v2')
    @json_api.authenticate
    def admin_v2(request):
        return {'scope': 'private', 'message': 'Access restricted content'}

    main_app.run('localhost', 8080)

main()