Tornado on python3 - sockets

Question

My goal is to run http server on python3 using tornado (http://www.tornadoweb.org/).
I started with running example code found on their webpage:
import tornado.httpserver
import tornado.ioloop
from tornado import httputil
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(8080)
tornado.ioloop.IOLoop.instance().start()
This code throws following exception when receiving any http request:
ERROR:tornado.application:Uncaught exception
Traceback (most recent call last):
File "/usr/local/lib/python3.4/dist-packages/tornado/http1connection.py", line 234, in _read_message
delegate.finish()
File "/usr/local/lib/python3.4/dist-packages/tornado/httpserver.py", line 280, in finish
self.server.request_callback(self.request)
File "test.py", line 10, in handle_request
{"Content-Length": str(len(message))})
File "/usr/local/lib/python3.4/dist-packages/tornado/http1connection.py", line 367, in write_headers
lines.extend([utf8(n) + b": " + utf8(v) for n, v in headers.get_all()])
AttributeError: 'dict' object has no attribute 'get_all'
Whats wrong ? This is sample code, so it should work and problem is somewhere in my enviroment ?
I tried this both on latest Ubuntu and Win 7 and it gave me same error.
Thanks in advance

Answer 1

The documentation had a bug, fixed recently. For any version of Python, you can't pass a raw dict to write_headers. Instead you must wrap the dict in an HTTPHeaders object. For Python 3, the message must be a bytes instance. With both fixes:
def handle_request(request):
message = ("You requested %s\n" % request.uri).encode('ascii')
request.connection.write_headers(
httputil.ResponseStartLine('HTTP/1.1', 200, 'OK'),
httputil.HTTPHeaders({"Content-Length": str(len(message))}))
request.connection.write(message)
request.connection.finish()