Imported from SVN by Bitbucket
This commit is contained in:
bitbucket
405
Paste-1.7.5.1-py2.6.egg/paste/recursive.py
Executable file
405
Paste-1.7.5.1-py2.6.egg/paste/recursive.py
Executable file
@@ -0,0 +1,405 @@
|
||||
# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
|
||||
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
|
||||
"""
|
||||
Middleware to make internal requests and forward requests internally.
|
||||
|
||||
When applied, several keys are added to the environment that will allow
|
||||
you to trigger recursive redirects and forwards.
|
||||
|
||||
paste.recursive.include:
|
||||
When you call
|
||||
``environ['paste.recursive.include'](new_path_info)`` a response
|
||||
will be returned. The response has a ``body`` attribute, a
|
||||
``status`` attribute, and a ``headers`` attribute.
|
||||
|
||||
paste.recursive.script_name:
|
||||
The ``SCRIPT_NAME`` at the point that recursive lives. Only
|
||||
paths underneath this path can be redirected to.
|
||||
|
||||
paste.recursive.old_path_info:
|
||||
A list of previous ``PATH_INFO`` values from previous redirects.
|
||||
|
||||
Raise ``ForwardRequestException(new_path_info)`` to do a forward
|
||||
(aborting the current request).
|
||||
"""
|
||||
|
||||
from cStringIO import StringIO
|
||||
import warnings
|
||||
|
||||
__all__ = ['RecursiveMiddleware']
|
||||
__pudge_all__ = ['RecursiveMiddleware', 'ForwardRequestException']
|
||||
|
||||
class RecursionLoop(AssertionError):
|
||||
# Subclasses AssertionError for legacy reasons
|
||||
"""Raised when a recursion enters into a loop"""
|
||||
|
||||
class CheckForRecursionMiddleware(object):
|
||||
def __init__(self, app, env):
|
||||
self.app = app
|
||||
self.env = env
|
||||
|
||||
def __call__(self, environ, start_response):
|
||||
path_info = environ.get('PATH_INFO','')
|
||||
if path_info in self.env.get(
|
||||
'paste.recursive.old_path_info', []):
|
||||
raise RecursionLoop(
|
||||
"Forwarding loop detected; %r visited twice (internal "
|
||||
"redirect path: %s)"
|
||||
% (path_info, self.env['paste.recursive.old_path_info']))
|
||||
old_path_info = self.env.setdefault('paste.recursive.old_path_info', [])
|
||||
old_path_info.append(self.env.get('PATH_INFO', ''))
|
||||
return self.app(environ, start_response)
|
||||
|
||||
class RecursiveMiddleware(object):
|
||||
|
||||
"""
|
||||
A WSGI middleware that allows for recursive and forwarded calls.
|
||||
All these calls go to the same 'application', but presumably that
|
||||
application acts differently with different URLs. The forwarded
|
||||
URLs must be relative to this container.
|
||||
|
||||
Interface is entirely through the ``paste.recursive.forward`` and
|
||||
``paste.recursive.include`` environmental keys.
|
||||
"""
|
||||
|
||||
def __init__(self, application, global_conf=None):
|
||||
self.application = application
|
||||
|
||||
def __call__(self, environ, start_response):
|
||||
environ['paste.recursive.forward'] = Forwarder(
|
||||
self.application,
|
||||
environ,
|
||||
start_response)
|
||||
environ['paste.recursive.include'] = Includer(
|
||||
self.application,
|
||||
environ,
|
||||
start_response)
|
||||
environ['paste.recursive.include_app_iter'] = IncluderAppIter(
|
||||
self.application,
|
||||
environ,
|
||||
start_response)
|
||||
my_script_name = environ.get('SCRIPT_NAME', '')
|
||||
environ['paste.recursive.script_name'] = my_script_name
|
||||
try:
|
||||
return self.application(environ, start_response)
|
||||
except ForwardRequestException, e:
|
||||
middleware = CheckForRecursionMiddleware(
|
||||
e.factory(self), environ)
|
||||
return middleware(environ, start_response)
|
||||
|
||||
class ForwardRequestException(Exception):
|
||||
"""
|
||||
Used to signal that a request should be forwarded to a different location.
|
||||
|
||||
``url``
|
||||
The URL to forward to starting with a ``/`` and relative to
|
||||
``RecursiveMiddleware``. URL fragments can also contain query strings
|
||||
so ``/error?code=404`` would be a valid URL fragment.
|
||||
|
||||
``environ``
|
||||
An altertative WSGI environment dictionary to use for the forwarded
|
||||
request. If specified is used *instead* of the ``url_fragment``
|
||||
|
||||
``factory``
|
||||
If specifed ``factory`` is used instead of ``url`` or ``environ``.
|
||||
``factory`` is a callable that takes a WSGI application object
|
||||
as the first argument and returns an initialised WSGI middleware
|
||||
which can alter the forwarded response.
|
||||
|
||||
Basic usage (must have ``RecursiveMiddleware`` present) :
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
from paste.recursive import ForwardRequestException
|
||||
def app(environ, start_response):
|
||||
if environ['PATH_INFO'] == '/hello':
|
||||
start_response("200 OK", [('Content-type', 'text/plain')])
|
||||
return ['Hello World!']
|
||||
elif environ['PATH_INFO'] == '/error':
|
||||
start_response("404 Not Found", [('Content-type', 'text/plain')])
|
||||
return ['Page not found']
|
||||
else:
|
||||
raise ForwardRequestException('/error')
|
||||
|
||||
from paste.recursive import RecursiveMiddleware
|
||||
app = RecursiveMiddleware(app)
|
||||
|
||||
If you ran this application and visited ``/hello`` you would get a
|
||||
``Hello World!`` message. If you ran the application and visited
|
||||
``/not_found`` a ``ForwardRequestException`` would be raised and the caught
|
||||
by the ``RecursiveMiddleware``. The ``RecursiveMiddleware`` would then
|
||||
return the headers and response from the ``/error`` URL but would display
|
||||
a ``404 Not found`` status message.
|
||||
|
||||
You could also specify an ``environ`` dictionary instead of a url. Using
|
||||
the same example as before:
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
def app(environ, start_response):
|
||||
... same as previous example ...
|
||||
else:
|
||||
new_environ = environ.copy()
|
||||
new_environ['PATH_INFO'] = '/error'
|
||||
raise ForwardRequestException(environ=new_environ)
|
||||
|
||||
Finally, if you want complete control over every aspect of the forward you
|
||||
can specify a middleware factory. For example to keep the old status code
|
||||
but use the headers and resposne body from the forwarded response you might
|
||||
do this:
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
from paste.recursive import ForwardRequestException
|
||||
from paste.recursive import RecursiveMiddleware
|
||||
from paste.errordocument import StatusKeeper
|
||||
|
||||
def app(environ, start_response):
|
||||
if environ['PATH_INFO'] == '/hello':
|
||||
start_response("200 OK", [('Content-type', 'text/plain')])
|
||||
return ['Hello World!']
|
||||
elif environ['PATH_INFO'] == '/error':
|
||||
start_response("404 Not Found", [('Content-type', 'text/plain')])
|
||||
return ['Page not found']
|
||||
else:
|
||||
def factory(app):
|
||||
return StatusKeeper(app, status='404 Not Found', url='/error')
|
||||
raise ForwardRequestException(factory=factory)
|
||||
|
||||
app = RecursiveMiddleware(app)
|
||||
"""
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
url=None,
|
||||
environ={},
|
||||
factory=None,
|
||||
path_info=None):
|
||||
# Check no incompatible options have been chosen
|
||||
if factory and url:
|
||||
raise TypeError(
|
||||
'You cannot specify factory and a url in '
|
||||
'ForwardRequestException')
|
||||
elif factory and environ:
|
||||
raise TypeError(
|
||||
'You cannot specify factory and environ in '
|
||||
'ForwardRequestException')
|
||||
if url and environ:
|
||||
raise TypeError(
|
||||
'You cannot specify environ and url in '
|
||||
'ForwardRequestException')
|
||||
|
||||
# set the path_info or warn about its use.
|
||||
if path_info:
|
||||
if not url:
|
||||
warnings.warn(
|
||||
"ForwardRequestException(path_info=...) has been deprecated; please "
|
||||
"use ForwardRequestException(url=...)",
|
||||
DeprecationWarning, 2)
|
||||
else:
|
||||
raise TypeError('You cannot use url and path_info in ForwardRequestException')
|
||||
self.path_info = path_info
|
||||
|
||||
# If the url can be treated as a path_info do that
|
||||
if url and not '?' in str(url):
|
||||
self.path_info = url
|
||||
|
||||
# Base middleware
|
||||
class ForwardRequestExceptionMiddleware(object):
|
||||
def __init__(self, app):
|
||||
self.app = app
|
||||
|
||||
# Otherwise construct the appropriate middleware factory
|
||||
if hasattr(self, 'path_info'):
|
||||
p = self.path_info
|
||||
def factory_(app):
|
||||
class PathInfoForward(ForwardRequestExceptionMiddleware):
|
||||
def __call__(self, environ, start_response):
|
||||
environ['PATH_INFO'] = p
|
||||
return self.app(environ, start_response)
|
||||
return PathInfoForward(app)
|
||||
self.factory = factory_
|
||||
elif url:
|
||||
def factory_(app):
|
||||
class URLForward(ForwardRequestExceptionMiddleware):
|
||||
def __call__(self, environ, start_response):
|
||||
environ['PATH_INFO'] = url.split('?')[0]
|
||||
environ['QUERY_STRING'] = url.split('?')[1]
|
||||
return self.app(environ, start_response)
|
||||
return URLForward(app)
|
||||
self.factory = factory_
|
||||
elif environ:
|
||||
def factory_(app):
|
||||
class EnvironForward(ForwardRequestExceptionMiddleware):
|
||||
def __call__(self, environ_, start_response):
|
||||
return self.app(environ, start_response)
|
||||
return EnvironForward(app)
|
||||
self.factory = factory_
|
||||
else:
|
||||
self.factory = factory
|
||||
|
||||
class Recursive(object):
|
||||
|
||||
def __init__(self, application, environ, start_response):
|
||||
self.application = application
|
||||
self.original_environ = environ.copy()
|
||||
self.previous_environ = environ
|
||||
self.start_response = start_response
|
||||
|
||||
def __call__(self, path, extra_environ=None):
|
||||
"""
|
||||
`extra_environ` is an optional dictionary that is also added
|
||||
to the forwarded request. E.g., ``{'HTTP_HOST': 'new.host'}``
|
||||
could be used to forward to a different virtual host.
|
||||
"""
|
||||
environ = self.original_environ.copy()
|
||||
if extra_environ:
|
||||
environ.update(extra_environ)
|
||||
environ['paste.recursive.previous_environ'] = self.previous_environ
|
||||
base_path = self.original_environ.get('SCRIPT_NAME')
|
||||
if path.startswith('/'):
|
||||
assert path.startswith(base_path), (
|
||||
"You can only forward requests to resources under the "
|
||||
"path %r (not %r)" % (base_path, path))
|
||||
path = path[len(base_path)+1:]
|
||||
assert not path.startswith('/')
|
||||
path_info = '/' + path
|
||||
environ['PATH_INFO'] = path_info
|
||||
environ['REQUEST_METHOD'] = 'GET'
|
||||
environ['CONTENT_LENGTH'] = '0'
|
||||
environ['CONTENT_TYPE'] = ''
|
||||
environ['wsgi.input'] = StringIO('')
|
||||
return self.activate(environ)
|
||||
|
||||
def activate(self, environ):
|
||||
raise NotImplementedError
|
||||
|
||||
def __repr__(self):
|
||||
return '<%s.%s from %s>' % (
|
||||
self.__class__.__module__,
|
||||
self.__class__.__name__,
|
||||
self.original_environ.get('SCRIPT_NAME') or '/')
|
||||
|
||||
class Forwarder(Recursive):
|
||||
|
||||
"""
|
||||
The forwarder will try to restart the request, except with
|
||||
the new `path` (replacing ``PATH_INFO`` in the request).
|
||||
|
||||
It must not be called after and headers have been returned.
|
||||
It returns an iterator that must be returned back up the call
|
||||
stack, so it must be used like:
|
||||
|
||||
.. code-block:: python
|
||||
|
||||
return environ['paste.recursive.forward'](path)
|
||||
|
||||
Meaningful transformations cannot be done, since headers are
|
||||
sent directly to the server and cannot be inspected or
|
||||
rewritten.
|
||||
"""
|
||||
|
||||
def activate(self, environ):
|
||||
warnings.warn(
|
||||
"recursive.Forwarder has been deprecated; please use "
|
||||
"ForwardRequestException",
|
||||
DeprecationWarning, 2)
|
||||
return self.application(environ, self.start_response)
|
||||
|
||||
|
||||
class Includer(Recursive):
|
||||
|
||||
"""
|
||||
Starts another request with the given path and adding or
|
||||
overwriting any values in the `extra_environ` dictionary.
|
||||
Returns an IncludeResponse object.
|
||||
"""
|
||||
|
||||
def activate(self, environ):
|
||||
response = IncludedResponse()
|
||||
def start_response(status, headers, exc_info=None):
|
||||
if exc_info:
|
||||
raise exc_info[0], exc_info[1], exc_info[2]
|
||||
response.status = status
|
||||
response.headers = headers
|
||||
return response.write
|
||||
app_iter = self.application(environ, start_response)
|
||||
try:
|
||||
for s in app_iter:
|
||||
response.write(s)
|
||||
finally:
|
||||
if hasattr(app_iter, 'close'):
|
||||
app_iter.close()
|
||||
response.close()
|
||||
return response
|
||||
|
||||
class IncludedResponse(object):
|
||||
|
||||
def __init__(self):
|
||||
self.headers = None
|
||||
self.status = None
|
||||
self.output = StringIO()
|
||||
self.str = None
|
||||
|
||||
def close(self):
|
||||
self.str = self.output.getvalue()
|
||||
self.output.close()
|
||||
self.output = None
|
||||
|
||||
def write(self, s):
|
||||
assert self.output is not None, (
|
||||
"This response has already been closed and no further data "
|
||||
"can be written.")
|
||||
self.output.write(s)
|
||||
|
||||
def __str__(self):
|
||||
return self.body
|
||||
|
||||
def body__get(self):
|
||||
if self.str is None:
|
||||
return self.output.getvalue()
|
||||
else:
|
||||
return self.str
|
||||
body = property(body__get)
|
||||
|
||||
|
||||
class IncluderAppIter(Recursive):
|
||||
"""
|
||||
Like Includer, but just stores the app_iter response
|
||||
(be sure to call close on the response!)
|
||||
"""
|
||||
|
||||
def activate(self, environ):
|
||||
response = IncludedAppIterResponse()
|
||||
def start_response(status, headers, exc_info=None):
|
||||
if exc_info:
|
||||
raise exc_info[0], exc_info[1], exc_info[2]
|
||||
response.status = status
|
||||
response.headers = headers
|
||||
return response.write
|
||||
app_iter = self.application(environ, start_response)
|
||||
response.app_iter = app_iter
|
||||
return response
|
||||
|
||||
class IncludedAppIterResponse(object):
|
||||
|
||||
def __init__(self):
|
||||
self.status = None
|
||||
self.headers = None
|
||||
self.accumulated = []
|
||||
self.app_iter = None
|
||||
self._closed = False
|
||||
|
||||
def close(self):
|
||||
assert not self._closed, (
|
||||
"Tried to close twice")
|
||||
if hasattr(self.app_iter, 'close'):
|
||||
self.app_iter.close()
|
||||
|
||||
def write(self, s):
|
||||
self.accumulated.append
|
||||
|
||||
def make_recursive_middleware(app, global_conf):
|
||||
return RecursiveMiddleware(app)
|
||||
|
||||
make_recursive_middleware.__doc__ = __doc__
|
||||
Reference in New Issue
Block a user