diff options
Diffstat (limited to 'cherrypy/_cpdispatch.py')
| -rw-r--r-- | cherrypy/_cpdispatch.py | 685 |
1 files changed, 0 insertions, 685 deletions
diff --git a/cherrypy/_cpdispatch.py b/cherrypy/_cpdispatch.py deleted file mode 100644 index 2cb03c7e..00000000 --- a/cherrypy/_cpdispatch.py +++ /dev/null @@ -1,685 +0,0 @@ -"""CherryPy dispatchers. - -A 'dispatcher' is the object which looks up the 'page handler' callable -and collects config for the current request based on the path_info, other -request attributes, and the application architecture. The core calls the -dispatcher as early as possible, passing it a 'path_info' argument. - -The default dispatcher discovers the page handler by matching path_info -to a hierarchical arrangement of objects, starting at request.app.root. -""" - -import string -import sys -import types -try: - classtype = (type, types.ClassType) -except AttributeError: - classtype = type - -import cherrypy - - -class PageHandler(object): - - """Callable which sets response.body.""" - - def __init__(self, callable, *args, **kwargs): - self.callable = callable - self.args = args - self.kwargs = kwargs - - def get_args(self): - return cherrypy.serving.request.args - - def set_args(self, args): - cherrypy.serving.request.args = args - return cherrypy.serving.request.args - - args = property( - get_args, - set_args, - doc="The ordered args should be accessible from post dispatch hooks" - ) - - def get_kwargs(self): - return cherrypy.serving.request.kwargs - - def set_kwargs(self, kwargs): - cherrypy.serving.request.kwargs = kwargs - return cherrypy.serving.request.kwargs - - kwargs = property( - get_kwargs, - set_kwargs, - doc="The named kwargs should be accessible from post dispatch hooks" - ) - - def __call__(self): - try: - return self.callable(*self.args, **self.kwargs) - except TypeError: - x = sys.exc_info()[1] - try: - test_callable_spec(self.callable, self.args, self.kwargs) - except cherrypy.HTTPError: - raise sys.exc_info()[1] - except: - raise x - raise - - -def test_callable_spec(callable, callable_args, callable_kwargs): - """ - Inspect callable and test to see if the given args are suitable for it. - - When an error occurs during the handler's invoking stage there are 2 - erroneous cases: - 1. Too many parameters passed to a function which doesn't define - one of *args or **kwargs. - 2. Too little parameters are passed to the function. - - There are 3 sources of parameters to a cherrypy handler. - 1. query string parameters are passed as keyword parameters to the - handler. - 2. body parameters are also passed as keyword parameters. - 3. when partial matching occurs, the final path atoms are passed as - positional args. - Both the query string and path atoms are part of the URI. If they are - incorrect, then a 404 Not Found should be raised. Conversely the body - parameters are part of the request; if they are invalid a 400 Bad Request. - """ - show_mismatched_params = getattr( - cherrypy.serving.request, 'show_mismatched_params', False) - try: - (args, varargs, varkw, defaults) = getargspec(callable) - except TypeError: - if isinstance(callable, object) and hasattr(callable, '__call__'): - (args, varargs, varkw, - defaults) = getargspec(callable.__call__) - else: - # If it wasn't one of our own types, re-raise - # the original error - raise - - if args and args[0] == 'self': - args = args[1:] - - arg_usage = dict([(arg, 0,) for arg in args]) - vararg_usage = 0 - varkw_usage = 0 - extra_kwargs = set() - - for i, value in enumerate(callable_args): - try: - arg_usage[args[i]] += 1 - except IndexError: - vararg_usage += 1 - - for key in callable_kwargs.keys(): - try: - arg_usage[key] += 1 - except KeyError: - varkw_usage += 1 - extra_kwargs.add(key) - - # figure out which args have defaults. - args_with_defaults = args[-len(defaults or []):] - for i, val in enumerate(defaults or []): - # Defaults take effect only when the arg hasn't been used yet. - if arg_usage[args_with_defaults[i]] == 0: - arg_usage[args_with_defaults[i]] += 1 - - missing_args = [] - multiple_args = [] - for key, usage in arg_usage.items(): - if usage == 0: - missing_args.append(key) - elif usage > 1: - multiple_args.append(key) - - if missing_args: - # In the case where the method allows body arguments - # there are 3 potential errors: - # 1. not enough query string parameters -> 404 - # 2. not enough body parameters -> 400 - # 3. not enough path parts (partial matches) -> 404 - # - # We can't actually tell which case it is, - # so I'm raising a 404 because that covers 2/3 of the - # possibilities - # - # In the case where the method does not allow body - # arguments it's definitely a 404. - message = None - if show_mismatched_params: - message = "Missing parameters: %s" % ",".join(missing_args) - raise cherrypy.HTTPError(404, message=message) - - # the extra positional arguments come from the path - 404 Not Found - if not varargs and vararg_usage > 0: - raise cherrypy.HTTPError(404) - - body_params = cherrypy.serving.request.body.params or {} - body_params = set(body_params.keys()) - qs_params = set(callable_kwargs.keys()) - body_params - - if multiple_args: - if qs_params.intersection(set(multiple_args)): - # If any of the multiple parameters came from the query string then - # it's a 404 Not Found - error = 404 - else: - # Otherwise it's a 400 Bad Request - error = 400 - - message = None - if show_mismatched_params: - message = "Multiple values for parameters: "\ - "%s" % ",".join(multiple_args) - raise cherrypy.HTTPError(error, message=message) - - if not varkw and varkw_usage > 0: - - # If there were extra query string parameters, it's a 404 Not Found - extra_qs_params = set(qs_params).intersection(extra_kwargs) - if extra_qs_params: - message = None - if show_mismatched_params: - message = "Unexpected query string "\ - "parameters: %s" % ", ".join(extra_qs_params) - raise cherrypy.HTTPError(404, message=message) - - # If there were any extra body parameters, it's a 400 Not Found - extra_body_params = set(body_params).intersection(extra_kwargs) - if extra_body_params: - message = None - if show_mismatched_params: - message = "Unexpected body parameters: "\ - "%s" % ", ".join(extra_body_params) - raise cherrypy.HTTPError(400, message=message) - - -try: - import inspect -except ImportError: - test_callable_spec = lambda callable, args, kwargs: None -else: - getargspec = inspect.getargspec - # Python 3 requires using getfullargspec if keyword-only arguments are present - if hasattr(inspect, 'getfullargspec'): - def getargspec(callable): - return inspect.getfullargspec(callable)[:4] - - -class LateParamPageHandler(PageHandler): - - """When passing cherrypy.request.params to the page handler, we do not - want to capture that dict too early; we want to give tools like the - decoding tool a chance to modify the params dict in-between the lookup - of the handler and the actual calling of the handler. This subclass - takes that into account, and allows request.params to be 'bound late' - (it's more complicated than that, but that's the effect). - """ - - def _get_kwargs(self): - kwargs = cherrypy.serving.request.params.copy() - if self._kwargs: - kwargs.update(self._kwargs) - return kwargs - - def _set_kwargs(self, kwargs): - cherrypy.serving.request.kwargs = kwargs - self._kwargs = kwargs - - kwargs = property(_get_kwargs, _set_kwargs, - doc='page handler kwargs (with ' - 'cherrypy.request.params copied in)') - - -if sys.version_info < (3, 0): - punctuation_to_underscores = string.maketrans( - string.punctuation, '_' * len(string.punctuation)) - - def validate_translator(t): - if not isinstance(t, str) or len(t) != 256: - raise ValueError( - "The translate argument must be a str of len 256.") -else: - punctuation_to_underscores = str.maketrans( - string.punctuation, '_' * len(string.punctuation)) - - def validate_translator(t): - if not isinstance(t, dict): - raise ValueError("The translate argument must be a dict.") - - -class Dispatcher(object): - - """CherryPy Dispatcher which walks a tree of objects to find a handler. - - The tree is rooted at cherrypy.request.app.root, and each hierarchical - component in the path_info argument is matched to a corresponding nested - attribute of the root object. Matching handlers must have an 'exposed' - attribute which evaluates to True. The special method name "index" - matches a URI which ends in a slash ("/"). The special method name - "default" may match a portion of the path_info (but only when no longer - substring of the path_info matches some other object). - - This is the default, built-in dispatcher for CherryPy. - """ - - dispatch_method_name = '_cp_dispatch' - """ - The name of the dispatch method that nodes may optionally implement - to provide their own dynamic dispatch algorithm. - """ - - def __init__(self, dispatch_method_name=None, - translate=punctuation_to_underscores): - validate_translator(translate) - self.translate = translate - if dispatch_method_name: - self.dispatch_method_name = dispatch_method_name - - def __call__(self, path_info): - """Set handler and config for the current request.""" - request = cherrypy.serving.request - func, vpath = self.find_handler(path_info) - - if func: - # Decode any leftover %2F in the virtual_path atoms. - vpath = [x.replace("%2F", "/") for x in vpath] - request.handler = LateParamPageHandler(func, *vpath) - else: - request.handler = cherrypy.NotFound() - - def find_handler(self, path): - """Return the appropriate page handler, plus any virtual path. - - This will return two objects. The first will be a callable, - which can be used to generate page output. Any parameters from - the query string or request body will be sent to that callable - as keyword arguments. - - The callable is found by traversing the application's tree, - starting from cherrypy.request.app.root, and matching path - components to successive objects in the tree. For example, the - URL "/path/to/handler" might return root.path.to.handler. - - The second object returned will be a list of names which are - 'virtual path' components: parts of the URL which are dynamic, - and were not used when looking up the handler. - These virtual path components are passed to the handler as - positional arguments. - """ - request = cherrypy.serving.request - app = request.app - root = app.root - dispatch_name = self.dispatch_method_name - - # Get config for the root object/path. - fullpath = [x for x in path.strip('/').split('/') if x] + ['index'] - fullpath_len = len(fullpath) - segleft = fullpath_len - nodeconf = {} - if hasattr(root, "_cp_config"): - nodeconf.update(root._cp_config) - if "/" in app.config: - nodeconf.update(app.config["/"]) - object_trail = [['root', root, nodeconf, segleft]] - - node = root - iternames = fullpath[:] - while iternames: - name = iternames[0] - # map to legal Python identifiers (e.g. replace '.' with '_') - objname = name.translate(self.translate) - - nodeconf = {} - subnode = getattr(node, objname, None) - pre_len = len(iternames) - if subnode is None: - dispatch = getattr(node, dispatch_name, None) - if dispatch and hasattr(dispatch, '__call__') and not \ - getattr(dispatch, 'exposed', False) and \ - pre_len > 1: - # Don't expose the hidden 'index' token to _cp_dispatch - # We skip this if pre_len == 1 since it makes no sense - # to call a dispatcher when we have no tokens left. - index_name = iternames.pop() - subnode = dispatch(vpath=iternames) - iternames.append(index_name) - else: - # We didn't find a path, but keep processing in case there - # is a default() handler. - iternames.pop(0) - else: - # We found the path, remove the vpath entry - iternames.pop(0) - segleft = len(iternames) - if segleft > pre_len: - # No path segment was removed. Raise an error. - raise cherrypy.CherryPyException( - "A vpath segment was added. Custom dispatchers may only " - + "remove elements. While trying to process " - + "{0} in {1}".format(name, fullpath) - ) - elif segleft == pre_len: - # Assume that the handler used the current path segment, but - # did not pop it. This allows things like - # return getattr(self, vpath[0], None) - iternames.pop(0) - segleft -= 1 - node = subnode - - if node is not None: - # Get _cp_config attached to this node. - if hasattr(node, "_cp_config"): - nodeconf.update(node._cp_config) - - # Mix in values from app.config for this path. - existing_len = fullpath_len - pre_len - if existing_len != 0: - curpath = '/' + '/'.join(fullpath[0:existing_len]) - else: - curpath = '' - new_segs = fullpath[fullpath_len - pre_len:fullpath_len - segleft] - for seg in new_segs: - curpath += '/' + seg - if curpath in app.config: - nodeconf.update(app.config[curpath]) - - object_trail.append([name, node, nodeconf, segleft]) - - def set_conf(): - """Collapse all object_trail config into cherrypy.request.config. - """ - base = cherrypy.config.copy() - # Note that we merge the config from each node - # even if that node was None. - for name, obj, conf, segleft in object_trail: - base.update(conf) - if 'tools.staticdir.dir' in conf: - base['tools.staticdir.section'] = '/' + \ - '/'.join(fullpath[0:fullpath_len - segleft]) - return base - - # Try successive objects (reverse order) - num_candidates = len(object_trail) - 1 - for i in range(num_candidates, -1, -1): - - name, candidate, nodeconf, segleft = object_trail[i] - if candidate is None: - continue - - # Try a "default" method on the current leaf. - if hasattr(candidate, "default"): - defhandler = candidate.default - if getattr(defhandler, 'exposed', False): - # Insert any extra _cp_config from the default handler. - conf = getattr(defhandler, "_cp_config", {}) - object_trail.insert( - i + 1, ["default", defhandler, conf, segleft]) - request.config = set_conf() - # See https://github.com/cherrypy/cherrypy/issues/613 - request.is_index = path.endswith("/") - return defhandler, fullpath[fullpath_len - segleft:-1] - - # Uncomment the next line to restrict positional params to - # "default". - # if i < num_candidates - 2: continue - - # Try the current leaf. - if getattr(candidate, 'exposed', False): - request.config = set_conf() - if i == num_candidates: - # We found the extra ".index". Mark request so tools - # can redirect if path_info has no trailing slash. - request.is_index = True - else: - # We're not at an 'index' handler. Mark request so tools - # can redirect if path_info has NO trailing slash. - # Note that this also includes handlers which take - # positional parameters (virtual paths). - request.is_index = False - return candidate, fullpath[fullpath_len - segleft:-1] - - # We didn't find anything - request.config = set_conf() - return None, [] - - -class MethodDispatcher(Dispatcher): - - """Additional dispatch based on cherrypy.request.method.upper(). - - Methods named GET, POST, etc will be called on an exposed class. - The method names must be all caps; the appropriate Allow header - will be output showing all capitalized method names as allowable - HTTP verbs. - - Note that the containing class must be exposed, not the methods. - """ - - def __call__(self, path_info): - """Set handler and config for the current request.""" - request = cherrypy.serving.request - resource, vpath = self.find_handler(path_info) - - if resource: - # Set Allow header - avail = [m for m in dir(resource) if m.isupper()] - if "GET" in avail and "HEAD" not in avail: - avail.append("HEAD") - avail.sort() - cherrypy.serving.response.headers['Allow'] = ", ".join(avail) - - # Find the subhandler - meth = request.method.upper() - func = getattr(resource, meth, None) - if func is None and meth == "HEAD": - func = getattr(resource, "GET", None) - if func: - # Grab any _cp_config on the subhandler. - if hasattr(func, "_cp_config"): - request.config.update(func._cp_config) - - # Decode any leftover %2F in the virtual_path atoms. - vpath = [x.replace("%2F", "/") for x in vpath] - request.handler = LateParamPageHandler(func, *vpath) - else: - request.handler = cherrypy.HTTPError(405) - else: - request.handler = cherrypy.NotFound() - - -class RoutesDispatcher(object): - - """A Routes based dispatcher for CherryPy.""" - - def __init__(self, full_result=False, **mapper_options): - """ - Routes dispatcher - - Set full_result to True if you wish the controller - and the action to be passed on to the page handler - parameters. By default they won't be. - """ - import routes - self.full_result = full_result - self.controllers = {} - self.mapper = routes.Mapper(**mapper_options) - self.mapper.controller_scan = self.controllers.keys - - def connect(self, name, route, controller, **kwargs): - self.controllers[name] = controller - self.mapper.connect(name, route, controller=name, **kwargs) - - def redirect(self, url): - raise cherrypy.HTTPRedirect(url) - - def __call__(self, path_info): - """Set handler and config for the current request.""" - func = self.find_handler(path_info) - if func: - cherrypy.serving.request.handler = LateParamPageHandler(func) - else: - cherrypy.serving.request.handler = cherrypy.NotFound() - - def find_handler(self, path_info): - """Find the right page handler, and set request.config.""" - import routes - - request = cherrypy.serving.request - - config = routes.request_config() - config.mapper = self.mapper - if hasattr(request, 'wsgi_environ'): - config.environ = request.wsgi_environ - config.host = request.headers.get('Host', None) - config.protocol = request.scheme - config.redirect = self.redirect - - result = self.mapper.match(path_info) - - config.mapper_dict = result - params = {} - if result: - params = result.copy() - if not self.full_result: - params.pop('controller', None) - params.pop('action', None) - request.params.update(params) - - # Get config for the root object/path. - request.config = base = cherrypy.config.copy() - curpath = "" - - def merge(nodeconf): - if 'tools.staticdir.dir' in nodeconf: - nodeconf['tools.staticdir.section'] = curpath or "/" - base.update(nodeconf) - - app = request.app - root = app.root - if hasattr(root, "_cp_config"): - merge(root._cp_config) - if "/" in app.config: - merge(app.config["/"]) - - # Mix in values from app.config. - atoms = [x for x in path_info.split("/") if x] - if atoms: - last = atoms.pop() - else: - last = None - for atom in atoms: - curpath = "/".join((curpath, atom)) - if curpath in app.config: - merge(app.config[curpath]) - - handler = None - if result: - controller = result.get('controller') - controller = self.controllers.get(controller, controller) - if controller: - if isinstance(controller, classtype): - controller = controller() - # Get config from the controller. - if hasattr(controller, "_cp_config"): - merge(controller._cp_config) - - action = result.get('action') - if action is not None: - handler = getattr(controller, action, None) - # Get config from the handler - if hasattr(handler, "_cp_config"): - merge(handler._cp_config) - else: - handler = controller - - # Do the last path atom here so it can - # override the controller's _cp_config. - if last: - curpath = "/".join((curpath, last)) - if curpath in app.config: - merge(app.config[curpath]) - - return handler - - -def XMLRPCDispatcher(next_dispatcher=Dispatcher()): - from cherrypy.lib import xmlrpcutil - - def xmlrpc_dispatch(path_info): - path_info = xmlrpcutil.patched_path(path_info) - return next_dispatcher(path_info) - return xmlrpc_dispatch - - -def VirtualHost(next_dispatcher=Dispatcher(), use_x_forwarded_host=True, - **domains): - """ - Select a different handler based on the Host header. - - This can be useful when running multiple sites within one CP server. - It allows several domains to point to different parts of a single - website structure. For example:: - - http://www.domain.example -> root - http://www.domain2.example -> root/domain2/ - http://www.domain2.example:443 -> root/secure - - can be accomplished via the following config:: - - [/] - request.dispatch = cherrypy.dispatch.VirtualHost( - **{'www.domain2.example': '/domain2', - 'www.domain2.example:443': '/secure', - }) - - next_dispatcher - The next dispatcher object in the dispatch chain. - The VirtualHost dispatcher adds a prefix to the URL and calls - another dispatcher. Defaults to cherrypy.dispatch.Dispatcher(). - - use_x_forwarded_host - If True (the default), any "X-Forwarded-Host" - request header will be used instead of the "Host" header. This - is commonly added by HTTP servers (such as Apache) when proxying. - - ``**domains`` - A dict of {host header value: virtual prefix} pairs. - The incoming "Host" request header is looked up in this dict, - and, if a match is found, the corresponding "virtual prefix" - value will be prepended to the URL path before calling the - next dispatcher. Note that you often need separate entries - for "example.com" and "www.example.com". In addition, "Host" - headers may contain the port number. - """ - from cherrypy.lib import httputil - - def vhost_dispatch(path_info): - request = cherrypy.serving.request - header = request.headers.get - - domain = header('Host', '') - if use_x_forwarded_host: - domain = header("X-Forwarded-Host", domain) - - prefix = domains.get(domain, "") - if prefix: - path_info = httputil.urljoin(prefix, path_info) - - result = next_dispatcher(path_info) - - # Touch up staticdir config. See - # https://github.com/cherrypy/cherrypy/issues/614. - section = request.config.get('tools.staticdir.section') - if section: - section = section[len(prefix):] - request.config['tools.staticdir.section'] = section - - return result - return vhost_dispatch |