A non-blocking, single-threaded HTTP server.
Typical applications have little direct interaction with the HTTPServer class except to start a server at the beginning of the process (and even that is often done indirectly via tornado.web.Application.listen).
Changed in version 3.3: The HTTPRequest class that used to live in this module has been moved to tornado.httputil.HTTPServerRequest. The old name remains as an alias.
A non-blocking, single-threaded HTTP server.
A server is defined by either a request callback that takes a HTTPServerRequest as an argument or a HTTPServerConnectionDelegate instance.
A simple example server that echoes back the URI you requested:
import tornado.httpserver
import tornado.ioloop
def handle_request(request):
message = "You requested %s\n" % request.uri
request.connection.write_headers(
httputil.ResponseStartLine('HTTP/1.1', 200, 'OK'),
{"Content-Length": str(len(message))})
request.connection.write(message)
request.connection.finish()
http_server = tornado.httpserver.HTTPServer(handle_request)
http_server.listen(8888)
tornado.ioloop.IOLoop.instance().start()
Applications should use the methods of HTTPConnection to write their response.
HTTPServer supports keep-alive connections by default (automatically for HTTP/1.1, or for HTTP/1.0 when the client requests Connection: keep-alive).
If xheaders is True, we support the X-Real-Ip/X-Forwarded-For and X-Scheme/X-Forwarded-Proto headers, which override the remote IP and URI scheme/protocol for all requests. These headers are useful when running Tornado behind a reverse proxy or load balancer. The protocol argument can also be set to https if Tornado is run behind an SSL-decoding proxy that does not set one of the supported xheaders.
To make this server serve SSL traffic, send the ssl_options dictionary argument with the arguments required for the ssl.wrap_socket method, including certfile and keyfile. (In Python 3.2+ you can pass an ssl.SSLContext object instead of a dict):
HTTPServer(applicaton, ssl_options={
"certfile": os.path.join(data_dir, "mydomain.crt"),
"keyfile": os.path.join(data_dir, "mydomain.key"),
})
HTTPServer initialization follows one of three patterns (the initialization methods are defined on tornado.tcpserver.TCPServer):
listen: simple single-process:
server = HTTPServer(app)
server.listen(8888)
IOLoop.instance().start()
In many cases, tornado.web.Application.listen can be used to avoid the need to explicitly create the HTTPServer.
bind/start: simple multi-process:
server = HTTPServer(app)
server.bind(8888)
server.start(0) # Forks multiple sub-processes
IOLoop.instance().start()
When using this interface, an IOLoop must not be passed to the HTTPServer constructor. start will always start the server on the default singleton IOLoop.
add_sockets: advanced multi-process:
sockets = tornado.netutil.bind_sockets(8888)
tornado.process.fork_processes(0)
server = HTTPServer(app)
server.add_sockets(sockets)
IOLoop.instance().start()
The add_sockets interface is more complicated, but it can be used with tornado.process.fork_processes to give you more flexibility in when the fork happens. add_sockets can also be used in single-process servers if you want to create your listening sockets in some way other than tornado.netutil.bind_sockets.
Changed in version 3.3: Added gzip, chunk_size, max_header_size, idle_connection_timeout, body_timeout, max_body_size arguments. Added support for HTTPServerConnectionDelegate instances as request_callback.