Source code for flump

"""
    flump
    ~~~~~
    An API builder which depends on Flask and Marshmallow and follows
    http://jsonapi.org.

    .. note:: Currently missing content negotation
             (http://jsonapi.org/format/#content-negotiation-servers), possibly
             to be added in a later version.

    :copyright: (c) 2015 by RolePoint.
"""

import logging

from flask import Blueprint, request
from werkzeug.exceptions import MethodNotAllowed

from .error_handlers import register_error_handlers
from .methods import HttpMethods
from .orm import OrmIntegration
from .fetcher import Fetcher
from .view import FlumpView, _FlumpMethodView
from .web_utils import MIMETYPE  # noqa

__version__ = "0.11.2"

__all__ = ['FlumpView', 'FlumpBlueprint', 'OrmIntegration', 'Fetcher',
           'HttpMethods']


class FlumpBlueprint(Blueprint):
    """
    A specialised Flask Blueprint for Marshmallow, which provides a convenience
    method for registering FlumpView routes.

    :param logging: If True, Provides some default logging. This logs the
                    request HTTP method, the kwargs passed to the view
                    endpoint, and the request JSON body.

    Adds the 'application/vnd.api+json' Content-Type header to all responses.
    """
    def __init__(self, *args, **kwargs):
        super(FlumpBlueprint, self).__init__(*args, **kwargs)

        register_error_handlers(self)

        if kwargs.pop('logging', False):
            @self.before_request
            def do_logging():
                logger = logging.getLogger('flump.view.{}'.format(self.name))

                debug_string = (
                    "%s request made for resource type %s with kwargs: %s "
                    "and data: %s"
                )

                logger.debug(debug_string, request.method, request.view_args,
                             request.data)

    def register_flump_view(self, view_class, url):
        """
        Registers the various URL rules for the given `flump_view` on the
        Blueprint.

        :param flump_view: The :class:`.view.FlumpView` to register URLs for.
        """
        flump_view = view_class()
        view_func = _FlumpMethodView.as_view(
            getattr(flump_view, 'VIEW_NAME', flump_view.RESOURCE_NAME),
            flump_view=flump_view
        )
        methods = flump_view.HTTP_METHODS

        # Our canonical URLs do not have a trailing slash.
        # Though we use `strict_slashes=False` to make sure the route matches
        # on both anyway.
        url = url.rstrip('/')

        url_mapping = flump_view.URL_MAPPING

        def register_endpoint(flump_method, flask_method):
            if flump_method in url_mapping:
                func = view_func if flump_method <= methods else _meth_not_allowed
                self.add_url_rule(
                    url_mapping[flump_method].format(url), methods=flask_method,
                    view_func=func, strict_slashes=False
                )

        register_endpoint(HttpMethods.GET, ('GET', ))
        register_endpoint(HttpMethods.GET_MANY, ('GET', ))
        register_endpoint(HttpMethods.POST, ('POST', ))
        register_endpoint(HttpMethods.PATCH, ('PATCH', ))
        register_endpoint(HttpMethods.DELETE, ('DELETE', ))

    def flump_view(self, url):
        """
        A class decorator for registering a flump view.

        :param url:   The URL to register the view under.
        """
        def flump_view_decorator(view_class):
            self.register_flump_view(view_class, url)
            return view_class

        return flump_view_decorator


def _meth_not_allowed(*args, **kwargs):
    """
    We implement a function which only raises MethodNotAllowed in order to
    return the correct response for methods not defined for a given flump_view.
    """
    raise MethodNotAllowed