"""WSGI interface (see PEP 333).""" import StringIO as _StringIO import sys as _sys import cherrypy as _cherrypy from cherrypy import _cperror, wsgiserver from cherrypy.lib import http as _http # Internal Redirect # class InternalRedirector(object): """WSGI middleware which handles cherrypy.InternalRedirect. When cherrypy.InternalRedirect is raised, this middleware traps it, rewrites the WSGI environ using the new path and query_string, and calls the next application again. Because the wsgi.input stream may have already been consumed by the next application, the redirected call will always be of HTTP method "GET", and therefore any params must be passed in the InternalRedirect object's query_string attribute. If you need something more complicated, make and raise your own exception and your own WSGI middleware to trap it. ;) It would be a bad idea to raise InternalRedirect after you've already yielded response content, although an enterprising soul could choose to abuse this. nextapp: the next application callable in the WSGI chain. recursive: if False (the default), each URL (path + qs) will be stored, and, if the same URL is requested again, RuntimeError will be raised. If 'recursive' is True, no such error will be raised. """ def __init__(self, nextapp, recursive=False): self.nextapp = nextapp self.recursive = recursive def __call__(self, environ, start_response): return IRResponse(self.nextapp, environ, start_response, self.recursive) class IRResponse(object): def __init__(self, nextapp, environ, start_response, recursive): self.redirections = [] self.recursive = recursive self.environ = environ.copy() self.nextapp = nextapp self.start_response = start_response self.response = None self.iter_response = None self.setapp() def setapp(self): while True: try: self.response = self.nextapp(self.environ, self.start_response) self.iter_response = iter(self.response) return except _cherrypy.InternalRedirect, ir: self.close() self.setenv(ir) def setenv(self, ir): env = self.environ if not self.recursive: if ir.path in self.redirections: raise RuntimeError("InternalRedirector visited the " "same URL twice: %r" % ir.path) else: # Add the *previous* path_info + qs to redirections. sn = env.get('SCRIPT_NAME', '') path = env.get('PATH_INFO', '') qs = env.get('QUERY_STRING', '') if qs: qs = "?" + qs self.redirections.append(sn + path + qs) # Munge environment and try again. env['REQUEST_METHOD'] = "GET" env['PATH_INFO'] = ir.path env['QUERY_STRING'] = ir.query_string env['wsgi.input'] = _StringIO.StringIO() env['CONTENT_LENGTH'] = "0" def close(self): if hasattr(self.response, "close"): self.response.close() def __iter__(self): return self def next(self): while True: try: return self.iter_response.next() except _cherrypy.InternalRedirect, ir: self.close() self.setenv(ir) self.setapp() # WSGI-to-CP Adapter # class AppResponse(object): throws = (KeyboardInterrupt, SystemExit, _cherrypy.InternalRedirect) request = None def __init__(self, environ, start_response, cpapp): try: self.request = self.get_engine_request(environ, cpapp) meth = environ['REQUEST_METHOD'] path = environ.get('SCRIPT_NAME', '') + environ.get('PATH_INFO', '') qs = environ.get('QUERY_STRING', '') rproto = environ.get('SERVER_PROTOCOL') headers = self.translate_headers(environ) rfile = environ['wsgi.input'] response = self.request.run(meth, path, qs, rproto, headers, rfile) s, h, b = response.status, response.header_list, response.body exc = None except self.throws: self.close() raise except: if getattr(self.request, "throw_errors", False): self.close() raise tb = _cperror.format_exc() _cherrypy.log(tb) if not getattr(self.request, "show_tracebacks", True): tb = "" s, h, b = _cperror.bare_error(tb) exc = _sys.exc_info() self.iter_response = iter(b) try: start_response(s, h, exc) except self.throws: self.close() raise except: if getattr(self.request, "throw_errors", False): self.close() raise _cherrypy.log(traceback=True) self.close() # CherryPy test suite expects bare_error body to be output, # so don't call start_response (which, according to PEP 333, # may raise its own error at that point). s, h, b = _cperror.bare_error() self.iter_response = iter(b) def __iter__(self): return self def next(self): try: chunk = self.iter_response.next() # WSGI requires all data to be of type "str". This coercion should # not take any time at all if chunk is already of type "str". # If it's unicode, it could be a big performance hit (x ~500). if not isinstance(chunk, str): chunk = chunk.encode("ISO-8859-1") return chunk except self.throws: raise except StopIteration: raise except: if getattr(self.request, "throw_errors", False): raise _cherrypy.log(traceback=True) # CherryPy test suite expects bare_error body to be output, # so don't call start_response (which, according to PEP 333, # may raise its own error at that point). s, h, b = _cperror.bare_error() self.iter_response = iter([]) return "".join(b) def close(self): if hasattr(self.request, "close"): try: self.request.close() except: _cherrypy.log(traceback=True) def get_engine_request(self, environ, cpapp): """Return a Request object from the CherryPy Engine using environ.""" env = environ.get local = _http.Host('', int(env('SERVER_PORT', 80)), env('SERVER_NAME', '')) remote = _http.Host(env('REMOTE_ADDR', ''), int(env('REMOTE_PORT', -1)), env('REMOTE_HOST', '')) scheme = env('wsgi.url_scheme') sproto = env('ACTUAL_SERVER_PROTOCOL', "HTTP/1.1") request = _cherrypy.engine.request(local, remote, scheme, sproto) # LOGON_USER is served by IIS, and is the name of the # user after having been mapped to a local account. # Both IIS and Apache set REMOTE_USER, when possible. request.login = env('LOGON_USER') or env('REMOTE_USER') or None request.multithread = environ['wsgi.multithread'] request.multiprocess = environ['wsgi.multiprocess'] request.wsgi_environ = environ request.app = cpapp request.prev = env('cherrypy.request') environ['cherrypy.request'] = request return request headerNames = {'HTTP_CGI_AUTHORIZATION': 'Authorization', 'CONTENT_LENGTH': 'Content-Length', 'CONTENT_TYPE': 'Content-Type', 'REMOTE_HOST': 'Remote-Host', 'REMOTE_ADDR': 'Remote-Addr', } def translate_headers(self, environ): """Translate CGI-environ header names to HTTP header names.""" for cgiName in environ: # We assume all incoming header keys are uppercase already. if cgiName in self.headerNames: yield self.headerNames[cgiName], environ[cgiName] elif cgiName[:5] == "HTTP_": # Hackish attempt at recovering original header names. translatedHeader = cgiName[5:].replace("_", "-") yield translatedHeader, environ[cgiName] class CPWSGIApp(object): """A WSGI application object for a CherryPy Application. pipeline: a list of (name, wsgiapp) pairs. Each 'wsgiapp' MUST be a constructor that takes an initial, positional 'nextapp' argument, plus optional keyword arguments, and returns a WSGI application (that takes environ and start_response arguments). The 'name' can be any you choose, and will correspond to keys in self.config. head: rather than nest all apps in the pipeline on each call, it's only done the first time, and the result is memoized into self.head. Set this to None again if you change self.pipeline after calling self. config: a dict whose keys match names listed in the pipeline. Each value is a further dict which will be passed to the corresponding named WSGI callable (from the pipeline) as keyword arguments. """ pipeline = [('iredir', InternalRedirector)] head = None config = {} response_class = AppResponse def __init__(self, cpapp, pipeline=None): self.cpapp = cpapp self.pipeline = self.pipeline[:] if pipeline: self.pipeline.extend(pipeline) self.config = self.config.copy() def tail(self, environ, start_response): """WSGI application callable for the actual CherryPy application. You probably shouldn't call this; call self.__call__ instead, so that any WSGI middleware in self.pipeline can run first. """ return self.response_class(environ, start_response, self.cpapp) def __call__(self, environ, start_response): head = self.head if head is None: # Create and nest the WSGI apps in our pipeline (in reverse order). # Then memoize the result in self.head. head = self.tail for name, callable in self.pipeline[::-1]: conf = self.config.get(name, {}) head = callable(head, **conf) self.head = head return head(environ, start_response) def namespace_handler(self, k, v): """Config handler for the 'wsgi' namespace.""" if k == "pipeline": # Note this allows multiple 'wsgi.pipeline' config entries # (but each entry will be processed in a 'random' order). # It should also allow developers to set default middleware # in code (passed to self.__init__) that deployers can add to # (but not remove) via config. self.pipeline.extend(v) else: name, arg = k.split(".", 1) bucket = self.config.setdefault(name, {}) bucket[arg] = v # Server components # class CPHTTPRequest(wsgiserver.HTTPRequest): def parse_request(self): mhs = _cherrypy.server.max_request_header_size if mhs > 0: self.rfile = _http.SizeCheckWrapper(self.rfile, mhs) try: wsgiserver.HTTPRequest.parse_request(self) except _http.MaxSizeExceeded: self.simple_response("413 Request Entity Too Large") _cherrypy.log(traceback=True) def decode_chunked(self): """Decode the 'chunked' transfer coding.""" if isinstance(self.rfile, _http.SizeCheckWrapper): self.rfile = self.rfile.rfile mbs = _cherrypy.server.max_request_body_size if mbs > 0: self.rfile = _http.SizeCheckWrapper(self.rfile, mbs) try: return wsgiserver.HTTPRequest.decode_chunked(self) except _http.MaxSizeExceeded: self.simple_response("413 Request Entity Too Large") _cherrypy.log(traceback=True) return False class CPHTTPConnection(wsgiserver.HTTPConnection): RequestHandlerClass = CPHTTPRequest class CPWSGIServer(wsgiserver.CherryPyWSGIServer): """Wrapper for wsgiserver.CherryPyWSGIServer. wsgiserver has been designed to not reference CherryPy in any way, so that it can be used in other frameworks and applications. Therefore, we wrap it here, so we can set our own mount points from cherrypy.tree. """ ConnectionClass = CPHTTPConnection def __init__(self): server = _cherrypy.server sockFile = server.socket_file if sockFile: bind_addr = sockFile else: bind_addr = (server.socket_host, server.socket_port) s = wsgiserver.CherryPyWSGIServer # We could just pass cherrypy.tree, but by passing tree.apps, # we get correct SCRIPT_NAMEs as early as possible. s.__init__(self, bind_addr, _cherrypy.tree.apps.items(), server.thread_pool, server.socket_host, request_queue_size = server.socket_queue_size, timeout = server.socket_timeout, ) self.protocol = server.protocol_version self.ssl_certificate = server.ssl_certificate self.ssl_private_key = server.ssl_private_key