"""CherryPy Application and Tree objects."""
import os
import cherrypy
from cherrypy import _cpconfig, _cplogging, _cprequest, _cpwsgi, tools
from cherrypy.lib import httputil, reprconf
[docs]class Application(object):
"""A CherryPy Application.
Servers and gateways should not instantiate Request objects
directly. Instead, they should ask an Application object for a
request object.
An instance of this class may also be used as a WSGI callable (WSGI
application object) for itself.
"""
root = None
"""The top-most container of page handlers for this app.
Handlers should be arranged in a hierarchy of attributes, matching
the expected URI hierarchy; the default dispatcher then searches
this hierarchy for a matching handler. When using a dispatcher other
than the default, this value may be None.
"""
config = {}
"""A dict of {path: pathconf} pairs, where 'pathconf' is itself a dict
of {key: value} pairs."""
namespaces = reprconf.NamespaceSet()
toolboxes = {'tools': cherrypy.tools}
log = None
"""A LogManager instance.
See _cplogging.
"""
wsgiapp = None
"""A CPWSGIApp instance.
See _cpwsgi.
"""
request_class = _cprequest.Request
response_class = _cprequest.Response
relative_urls = False
def __init__(self, root, script_name='', config=None):
"""Initialize Application with given root."""
self.log = _cplogging.LogManager(id(self), cherrypy.log.logger_root)
self.root = root
self.script_name = script_name
self.wsgiapp = _cpwsgi.CPWSGIApp(self)
self.namespaces = self.namespaces.copy()
self.namespaces['log'] = lambda k, v: setattr(self.log, k, v)
self.namespaces['wsgi'] = self.wsgiapp.namespace_handler
self.config = self.__class__.config.copy()
if config:
self.merge(config)
def __repr__(self):
"""Generate a representation of the Application instance."""
return '%s.%s(%r, %r)' % (self.__module__, self.__class__.__name__,
self.root, self.script_name)
script_name_doc = """The URI "mount point" for this app. A mount point
is that portion of the URI which is constant for all URIs that are
serviced by this application; it does not include scheme, host, or proxy
("virtual host") portions of the URI.
For example, if script_name is "/my/cool/app", then the URL
"http://www.example.com/my/cool/app/page1" might be handled by a
"page1" method on the root object.
The value of script_name MUST NOT end in a slash. If the script_name
refers to the root of the URI, it MUST be an empty string (not "/").
If script_name is explicitly set to None, then the script_name will be
provided for each call from request.wsgi_environ['SCRIPT_NAME'].
"""
@property
def script_name(self): # noqa: D401; irrelevant for properties
"""The URI "mount point" for this app.
A mount point is that portion of the URI which is constant for
all URIs that are serviced by this application; it does not
include scheme, host, or proxy ("virtual host") portions of the
URI.
For example, if script_name is "/my/cool/app", then the URL "
http://www.example.com/my/cool/app/page1"
might be handled by a
"page1" method on the root object.
The value of script_name MUST NOT end in a slash. If the script_name
refers to the root of the URI, it MUST be an empty string (not "/").
If script_name is explicitly set to None, then the script_name will be
provided for each call from request.wsgi_environ['SCRIPT_NAME'].
"""
if self._script_name is not None:
return self._script_name
# A `_script_name` with a value of None signals that the script name
# should be pulled from WSGI environ.
return cherrypy.serving.request.wsgi_environ['SCRIPT_NAME'].rstrip('/')
@script_name.setter
def script_name(self, value):
if value:
value = value.rstrip('/')
self._script_name = value
[docs] def merge(self, config):
"""Merge the given config into self.config."""
_cpconfig.merge(self.config, config)
# Handle namespaces specified in config.
self.namespaces(self.config.get('/', {}))
[docs] def find_config(self, path, key, default=None):
"""Return the most-specific value for key along path, or default."""
trail = path or '/'
while trail:
nodeconf = self.config.get(trail, {})
if key in nodeconf:
return nodeconf[key]
lastslash = trail.rfind('/')
if lastslash == -1:
break
elif lastslash == 0 and trail != '/':
trail = '/'
else:
trail = trail[:lastslash]
return default
[docs] def get_serving(self, local, remote, scheme, sproto):
"""Create and return a Request and Response object."""
req = self.request_class(local, remote, scheme, sproto)
req.app = self
for name, toolbox in self.toolboxes.items():
req.namespaces[name] = toolbox
resp = self.response_class()
cherrypy.serving.load(req, resp)
cherrypy.engine.publish('acquire_thread')
cherrypy.engine.publish('before_request')
return req, resp
[docs] def release_serving(self):
"""Release the current serving (request and response)."""
req = cherrypy.serving.request
cherrypy.engine.publish('after_request')
try:
req.close()
except Exception:
cherrypy.log(traceback=True, severity=40)
cherrypy.serving.clear()
def __call__(self, environ, start_response):
"""Call a WSGI-callable."""
return self.wsgiapp(environ, start_response)
[docs]class Tree(object):
"""A registry of CherryPy applications, mounted at diverse points.
An instance of this class may also be used as a WSGI callable (WSGI
application object), in which case it dispatches to all mounted
apps.
"""
apps = {}
"""
A dict of the form {script name: application}, where "script name"
is a string declaring the URI mount point (no trailing slash), and
"application" is an instance of cherrypy.Application (or an arbitrary
WSGI callable if you happen to be using a WSGI server)."""
def __init__(self):
"""Initialize registry Tree."""
self.apps = {}
[docs] def mount(self, root, script_name='', config=None):
"""Mount a new app from a root object, script_name, and config.
root
An instance of a "controller class" (a collection of page
handler methods) which represents the root of the application.
This may also be an Application instance, or None if using
a dispatcher other than the default.
script_name
A string containing the "mount point" of the application.
This should start with a slash, and be the path portion of the
URL at which to mount the given root. For example, if root.index()
will handle requests to "http://www.example.com:8080/dept/app1/",
then the script_name argument would be "/dept/app1".
It MUST NOT end in a slash. If the script_name refers to the
root of the URI, it MUST be an empty string (not "/").
config
A file or dict containing application config.
"""
if script_name is None:
raise TypeError(
"The 'script_name' argument may not be None. Application "
'objects may, however, possess a script_name of None (in '
'order to inpect the WSGI environ for SCRIPT_NAME upon each '
'request). You cannot mount such Applications on this Tree; '
'you must pass them to a WSGI server interface directly.')
# Next line both 1) strips trailing slash and 2) maps "/" -> "".
script_name = script_name.rstrip('/')
if isinstance(root, Application):
app = root
if script_name != '' and script_name != app.script_name:
raise ValueError(
'Cannot specify a different script name and pass an '
'Application instance to cherrypy.mount')
script_name = app.script_name
else:
app = Application(root, script_name)
# If mounted at "", add favicon.ico
needs_favicon = (
script_name == ''
and root is not None
and not hasattr(root, 'favicon_ico')
)
if needs_favicon:
favicon = os.path.join(
os.getcwd(),
os.path.dirname(__file__),
'favicon.ico',
)
root.favicon_ico = tools.staticfile.handler(favicon)
if config:
app.merge(config)
self.apps[script_name] = app
return app
[docs] def graft(self, wsgi_callable, script_name=''):
"""Mount a wsgi callable at the given script_name."""
# Next line both 1) strips trailing slash and 2) maps "/" -> "".
script_name = script_name.rstrip('/')
self.apps[script_name] = wsgi_callable
[docs] def script_name(self, path=None):
"""Return the script_name of the app at the given path, or None.
If path is None, cherrypy.request is used.
"""
if path is None:
try:
request = cherrypy.serving.request
path = httputil.urljoin(request.script_name,
request.path_info)
except AttributeError:
return None
while True:
if path in self.apps:
return path
if path == '':
return None
# Move one node up the tree and try again.
path = path[:path.rfind('/')]
def __call__(self, environ, start_response):
"""Pre-initialize WSGI env and call WSGI-callable."""
# If you're calling this, then you're probably setting SCRIPT_NAME
# to '' (some WSGI servers always set SCRIPT_NAME to '').
# Try to look up the app using the full path.
env1x = environ
path = httputil.urljoin(env1x.get('SCRIPT_NAME', ''),
env1x.get('PATH_INFO', ''))
sn = self.script_name(path or '/')
if sn is None:
start_response('404 Not Found', [])
return []
app = self.apps[sn]
# Correct the SCRIPT_NAME and PATH_INFO environ entries.
environ = environ.copy()
environ['SCRIPT_NAME'] = sn
environ['PATH_INFO'] = path[len(sn.rstrip('/')):]
return app(environ, start_response)
