register_api

register.py

def register_api(view, endpoint, url, pk='user_id', pk_type='int', alt_keys=None):
    """Registers a MethodView derived class as a REST API by exposing the
       various HTTP verbs to the correct URL schemes.  Allows alternative
       GET access for specific objects outside of the primary key GET scheme.
       These are defined by the `alt_keys` list.

       `alt_keys` is a list that can contain either strings or lists of strings.
       If the data are strings, it will generate a single alternate GET URL
       scheme inferring the type from the data contained in those strings.

       If it's a list of strings, it will generate a new GET URL for each list
       of strings.

       Ex:

           alt_keys=['date', 'slug'] becomes: [url provided]/<date>/<slug>

           alt_keys=['float:value'] becomes: [url provided]/<float:value>

           alt_keys[['date', 'slug'], ['int:user_id', 'date', 'slug']] becomes:
              [url provided]/<date>/<slug>
              [url provided]/<int:user_id>/<date>/<slug>
    """

    def make_url_component(url_key):
        if ':' in url_key:
            (t, k) = url_key.split(':')
            if t in ['int', 'path', 'float']:
                component =  "<%s:%s>" % (t, k)
            else:
              raise ValueError('Unknown type: %s in %s' % (t, url_key))
        else:
            component = "<%s>" % url_key
        return component

    def make_relative_url(path_list):
        path = []
        for component in path_list:
            path.append(make_url_component(component))
        return "/".join(path)

    def add_routing_rule(url, relative_path, view_func, methods, endpoint):
        app.add_url_rule("%s%s" % (url, relative_path), view_func=view_func,
                         methods=methods)

    # generate the default set of URL schemes
    view_func = view.as_view(endpoint)
    app.add_url_rule(url, defaults={pk: None},
                     view_func=view_func, methods=['GET',])
    app.add_url_rule(url, view_func=view_func, methods=['POST',])
    app.add_url_rule('%s<%s:%s>' % (url, pk_type, pk), view_func=view_func,
                     methods=['GET', 'PUT', 'DELETE'])

    # if there are alternative schemes provided, parse and add them
    if alt_keys and isinstance(alt_keys, list) and len(alt_keys) > 0:
        if isinstance(alt_keys[0], list):
            for key in alt_keys:
                add_routing_rule(url, make_relative_url(key), view_func,
                                 ['GET',], endpoint)
        else:
            add_routing_rule(url, make_relative_url(alt_keys), view_func,
                             ['GET',], endpoint)

usage.py

register_api(UserEntryAPI, "user_entry_api", "/rest/user/entry/", pk="entry_id",
             pk_type="int", alt_keys=['date', 'slug'])