#!/usr/bin/env python # # Copyright 2009 Facebook # # 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. """WSGI support for the Tornado web framework. WSGI is the Python standard for web servers, and allows for interoperability between Tornado and other Python web frameworks and servers. This module provides WSGI support in two ways: * `WSGIApplication` is a version of `tornado.web.Application` that can run inside a WSGI server. This is useful for running a Tornado app on another HTTP server, such as Google App Engine. See the `WSGIApplication` class documentation for limitations that apply. * `WSGIContainer` lets you run other WSGI applications and frameworks on the Tornado HTTP server. For example, with this class you can mix Django and Tornado handlers in a single server. """ import Cookie import cgi import httplib import logging import sys import time import tornado import urllib from tornado import escape from tornado import httputil from tornado import web from tornado.escape import native_str, utf8 from tornado.util import b try: from io import BytesIO # python 3 except ImportError: from cStringIO import StringIO as BytesIO # python 2 class WSGIApplication(web.Application): """A WSGI equivalent of `tornado.web.Application`. WSGIApplication is very similar to web.Application, except no asynchronous methods are supported (since WSGI does not support non-blocking requests properly). If you call self.flush() or other asynchronous methods in your request handlers running in a WSGIApplication, we throw an exception. Example usage:: import tornado.web import tornado.wsgi import wsgiref.simple_server class MainHandler(tornado.web.RequestHandler): def get(self): self.write("Hello, world") if __name__ == "__main__": application = tornado.wsgi.WSGIApplication([ (r"/", MainHandler), ]) server = wsgiref.simple_server.make_server('', 8888, application) server.serve_forever() See the 'appengine' demo for an example of using this module to run a Tornado app on Google AppEngine. Since no asynchronous methods are available for WSGI applications, the httpclient and auth modules are both not available for WSGI applications. We support the same interface, but handlers running in a WSGIApplication do not support flush() or asynchronous methods. """ def __init__(self, handlers=None, default_host="", **settings): web.Application.__init__(self, handlers, default_host, transforms=[], wsgi=True, **settings) def __call__(self, environ, start_response): handler = web.Application.__call__(self, HTTPRequest(environ)) assert handler._finished status = str(handler._status_code) + " " + \ httplib.responses[handler._status_code] headers = handler._headers.items() for cookie_dict in getattr(handler, "_new_cookies", []): for cookie in cookie_dict.values(): headers.append(("Set-Cookie", cookie.OutputString(None))) start_response(status, [(native_str(k), native_str(v)) for (k,v) in headers]) return handler._write_buffer class HTTPRequest(object): """Mimics `tornado.httpserver.HTTPRequest` for WSGI applications.""" def __init__(self, environ): """Parses the given WSGI environ to construct the request.""" self.method = environ["REQUEST_METHOD"] self.path = urllib.quote(environ.get("SCRIPT_NAME", "")) self.path += urllib.quote(environ.get("PATH_INFO", "")) self.uri = self.path self.arguments = {} self.query = environ.get("QUERY_STRING", "") if self.query: self.uri += "?" + self.query arguments = cgi.parse_qs(self.query) for name, values in arguments.iteritems(): values = [v for v in values if v] if values: self.arguments[name] = values self.version = "HTTP/1.1" self.headers = httputil.HTTPHeaders() if environ.get("CONTENT_TYPE"): self.headers["Content-Type"] = environ["CONTENT_TYPE"] if environ.get("CONTENT_LENGTH"): self.headers["Content-Length"] = environ["CONTENT_LENGTH"] for key in environ: if key.startswith("HTTP_"): self.headers[key[5:].replace("_", "-")] = environ[key] if self.headers.get("Content-Length"): self.body = environ["wsgi.input"].read( int(self.headers["Content-Length"])) else: self.body = "" self.protocol = environ["wsgi.url_scheme"] self.remote_ip = environ.get("REMOTE_ADDR", "") if environ.get("HTTP_HOST"): self.host = environ["HTTP_HOST"] else: self.host = environ["SERVER_NAME"] # Parse request body self.files = {} content_type = self.headers.get("Content-Type", "") if content_type.startswith("application/x-www-form-urlencoded"): for name, values in cgi.parse_qs(self.body).iteritems(): self.arguments.setdefault(name, []).extend(values) elif content_type.startswith("multipart/form-data"): if 'boundary=' in content_type: boundary = content_type.split('boundary=',1)[1] if boundary: httputil.parse_multipart_form_data( utf8(boundary), self.body, self.arguments, self.files) else: logging.warning("Invalid multipart/form-data") self._start_time = time.time() self._finish_time = None def supports_http_1_1(self): """Returns True if this request supports HTTP/1.1 semantics""" return self.version == "HTTP/1.1" @property def cookies(self): """A dictionary of Cookie.Morsel objects.""" if not hasattr(self, "_cookies"): self._cookies = Cookie.SimpleCookie() if "Cookie" in self.headers: try: self._cookies.load( native_str(self.headers["Cookie"])) except Exception: self._cookies = None return self._cookies def full_url(self): """Reconstructs the full URL for this request.""" return self.protocol + "://" + self.host + self.uri def request_time(self): """Returns the amount of time it took for this request to execute.""" if self._finish_time is None: return time.time() - self._start_time else: return self._finish_time - self._start_time class WSGIContainer(object): r"""Makes a WSGI-compatible function runnable on Tornado's HTTP server. Wrap a WSGI function in a WSGIContainer and pass it to HTTPServer to run it. For example:: def simple_app(environ, start_response): status = "200 OK" response_headers = [("Content-type", "text/plain")] start_response(status, response_headers) return ["Hello world!\n"] container = tornado.wsgi.WSGIContainer(simple_app) http_server = tornado.httpserver.HTTPServer(container) http_server.listen(8888) tornado.ioloop.IOLoop.instance().start() This class is intended to let other frameworks (Django, web.py, etc) run on the Tornado HTTP server and I/O loop. The `tornado.web.FallbackHandler` class is often useful for mixing Tornado and WSGI apps in the same server. See https://github.com/bdarnell/django-tornado-demo for a complete example. """ def __init__(self, wsgi_application): self.wsgi_application = wsgi_application def __call__(self, request): data = {} response = [] def start_response(status, response_headers, exc_info=None): data["status"] = status data["headers"] = response_headers return response.append app_response = self.wsgi_application( WSGIContainer.environ(request), start_response) response.extend(app_response) body = b("").join(response) if hasattr(app_response, "close"): app_response.close() if not data: raise Exception("WSGI app did not call start_response") status_code = int(data["status"].split()[0]) headers = data["headers"] header_set = set(k.lower() for (k,v) in headers) body = escape.utf8(body) if "content-length" not in header_set: headers.append(("Content-Length", str(len(body)))) if "content-type" not in header_set: headers.append(("Content-Type", "text/html; charset=UTF-8")) if "server" not in header_set: headers.append(("Server", "TornadoServer/%s" % tornado.version)) parts = [escape.utf8("HTTP/1.1 " + data["status"] + "\r\n")] for key, value in headers: parts.append(escape.utf8(key) + b(": ") + escape.utf8(value) + b("\r\n")) parts.append(b("\r\n")) parts.append(body) request.write(b("").join(parts)) request.finish() self._log(status_code, request) @staticmethod def environ(request): """Converts a `tornado.httpserver.HTTPRequest` to a WSGI environment. """ hostport = request.host.split(":") if len(hostport) == 2: host = hostport[0] port = int(hostport[1]) else: host = request.host port = 443 if request.protocol == "https" else 80 environ = { "REQUEST_METHOD": request.method, "SCRIPT_NAME": "", "PATH_INFO": urllib.unquote(request.path), "QUERY_STRING": request.query, "REMOTE_ADDR": request.remote_ip, "SERVER_NAME": host, "SERVER_PORT": str(port), "SERVER_PROTOCOL": request.version, "wsgi.version": (1, 0), "wsgi.url_scheme": request.protocol, "wsgi.input": BytesIO(escape.utf8(request.body)), "wsgi.errors": sys.stderr, "wsgi.multithread": False, "wsgi.multiprocess": True, "wsgi.run_once": False, } if "Content-Type" in request.headers: environ["CONTENT_TYPE"] = request.headers.pop("Content-Type") if "Content-Length" in request.headers: environ["CONTENT_LENGTH"] = request.headers.pop("Content-Length") for key, value in request.headers.iteritems(): environ["HTTP_" + key.replace("-", "_").upper()] = value return environ def _log(self, status_code, request): if status_code < 400: log_method = logging.info elif status_code < 500: log_method = logging.warning else: log_method = logging.error request_time = 1000.0 * request.request_time() summary = request.method + " " + request.uri + " (" + \ request.remote_ip + ")" log_method("%d %s %.2fms", status_code, summary, request_time)