# Copyright 2011 Dustin C. Hatch
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
'''Stub controller classes
These classes can be used as base classes for controllers. While any
callable can technically be a controller, using a class that inherits
from one or more of these classes can make things significantly easier.
:Created: Mar 27, 2011
:Author: dustin
'''
import datetime
import milla.util
import os
try:
import pkg_resources
except ImportError:
pkg_resources = None
[docs]class Controller(object):
'''The base controller class
This class simply provides empty ``__before__`` and ``__after__``
methods to facilitate cooperative multiple inheritance.
'''
def __before__(self, request):
pass
def __after__(self, request):
pass
[docs]class FaviconController(Controller):
'''A controller for the "favicon"
This controller is specifically suited to serve a site "favicon" or
bookmark icon. By default, it will serve the *Milla* icon, but you
can pass an alternate filename to the constructor.
:param icon: Path to an icon to serve
:param content_type: Internet media type describing the type of image
used as the favicon, defaults to 'image/x-icon' (Windows ICO format)
'''
#: Number of days in the future to set the cache expiration for the icon
EXPIRY_DAYS = 365
def __init__(self, icon=None, content_type='image/x-icon'):
try:
if icon:
self.icon = open(icon, 'rb')
self.content_type = content_type
elif pkg_resources:
self.icon = pkg_resources.resource_stream('milla', 'milla.ico')
self.content_type = 'image/x-icon'
else:
icon = os.path.join(
os.path.dirname(milla.__file__),
'milla.ico'
)
self.icon = open(icon, 'rb')
self.content_type = 'image/x-icon'
except (IOError, OSError):
self.icon = self.content_type = None
def __call__(self, request):
if not self.icon:
raise milla.HTTPNotFound
response = milla.Response()
response.app_iter = self.icon
response.headers['Content-Type'] = self.content_type
expires = (datetime.datetime.utcnow() +
datetime.timedelta(days=self.EXPIRY_DAYS))
response.headers['Expires'] = milla.util.http_date(expires)
return response
[docs]class HTTPVerbController(Controller):
'''A controller that delegates requests based on the HTTP method
Subclasses of this controller should have an instance method for
every HTTP method they support. For example, to support the ``GET``
and ``POST`` methods, a class might look like this:
.. code-block:: python
class MyController(HTTPVerbController):
def GET(self, request):
return 'Hello, world!'
HEAD = GET
def POST(self, request):
return 'Thanks!'
This example also allows ``HEAD`` requests, by processing them as
``GET`` requests. *Milla* handles this correctly, as it does not
send a response body for ``HEAD`` requests, even if the controller
callable returns one.
'''
def __call__(self, request, *args, **kwargs):
try:
func = getattr(self, request.method)
except AttributeError:
raise milla.HTTPMethodNotAllowed
return func(request, *args, **kwargs)
@property
def allowed_methods(self):
for attr in dir(self):
if attr.upper() == attr:
yield attr