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it seems that problem is someone connecting to port 8080 with non-http client, could not find warning in documentation
---fragment of `less access.log`------------
81.172.30.254 - - [16/Jun/2013 11:36:58] "^SBitTorrent protocol^@^@^@^@^@^X^@^Ej
81.172.30.254 - - [16/Jun/2013 11:38:11] "^N<U+008E>^@f ̧ãÄòQ;3x<U+0092>b^C^HÄA7
81.172.30.254 - - [16/Jun/2013 11:39:22] "^SBitTorrent protocol^@^@^@^@^@^X^@^Ej
81.172.30.254 - - [16/Jun/2013 11:40:35] "Ã<U+008D>¬0æz<U+0093>zr^D<U+009B>2]WQ
Exception happened during processing of request from ('81.172.30.254', 63650)
Traceback (most recent call last):
 File "c:\Python33\lib\socketserver.py", line 306, in _handle_request_noblock
 self.process_request(request, client_address)
 File "c:\Python33\lib\socketserver.py", line 332, in process_request
 self.finish_request(request, client_address)
 File "c:\Python33\lib\socketserver.py", line 345, in finish_request
 self.RequestHandlerClass(request, client_address, self)
 File "c:\Python33\lib\socketserver.py", line 666, in __init__
 self.handle()
 File "c:\Python33\lib\http\server.py", line 400, in handle
 self.handle_one_request()
 File "c:\Python33\lib\http\server.py", line 380, in handle_one_request
 if not self.parse_request():
 File "c:\Python33\lib\http\server.py", line 283, in parse_request
 self.send_error(400, "Bad request version (%r)" % version)
 File "c:\Python33\lib\http\server.py", line 428, in send_error
 self.send_response(code, message)
 File "c:\Python33\lib\http\server.py", line 443, in send_response
 self.log_request(code)
 File "c:\Users\joru\Dropbox\programowanie\demoniszcze\server\_lowerHTTP.py", line 30, in log_request
 xff=req.headers.get('X-Forwarded-For')
AttributeError: '_HNDL_3' object has no attribute 'headers'
# _HNLD_3 derives from http.server.BaseHTTPRequestHandler

This appears to be a bug in the _lowerHTTP module, which does not ship with Python.

what _lowerHTTP does is try read request header 'X-Forwarded-For', but instance of request handler have attribute headers only if thing that connected to port where server listens happened to send valid enough http request
my problem is, documentation does not help write code that would not crash when client sends random bytes instead of expected http request

#minimal server:
#!/c/Python33/python.exe
from http.server import HTTPServer as S, BaseHTTPRequestHandler as H
class HNDL(H):
	def log_request(req,code):
		print('header is',req.headers.get('X-Forwarder-For'),', code',code)
		H.log_request(req)
s=S(('',54321),HNDL)
s.serve_forever()
#non-http client:
#!/c/Python33/python.exe
import socket,os
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('localhost', 54321))
s.sendall(os.urandom(1024))
buf=s.recv(2048)
s.close()
print(buf)
#running server:
$ ./server.py
127.0.0.1 - - [06/Oct/2013 17:33:41] code 400, message Bad HTTP/0.9 request type
 ('E)\xaeE^2¤\xf2W\x8f\xb3aG')
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 18234)
Traceback (most recent call last):
 File "c:\Python33\lib\socketserver.py", line 306, in _handle_request_noblock
 self.process_request(request, client_address)
 File "c:\Python33\lib\socketserver.py", line 332, in process_request
 self.finish_request(request, client_address)
 File "c:\Python33\lib\socketserver.py", line 345, in finish_request
 self.RequestHandlerClass(request, client_address, self)
 File "c:\Python33\lib\socketserver.py", line 666, in __init__
 self.handle()
 File "c:\Python33\lib\http\server.py", line 400, in handle
 self.handle_one_request()
 File "c:\Python33\lib\http\server.py", line 380, in handle_one_request
 if not self.parse_request():
 File "c:\Python33\lib\http\server.py", line 311, in parse_request
 "Bad HTTP/0.9 request type (%r)" % command)
 File "c:\Python33\lib\http\server.py", line 428, in send_error
 self.send_response(code, message)
 File "c:\Python33\lib\http\server.py", line 443, in send_response
 self.log_request(code)
 File "./server.py", line 5, in log_request
 print('header is',req.headers.get('X-Forwarder-For'),', code',code)
AttributeError: 'HNDL' object has no attribute 'headers'
----------------------------------------
#running client:
$ ./client.py
b''
$

OK, so I guess it could be documented that the "headers" attribute is not set if the request cannot be parsed as a HTTP request. That's a valid point.
By the way, you should really call your "self" argument "self".

Added comment to documentation concerning when the headers attribute gets set. 
I confirmed that the headers attribute is only ever set in the parse_request method of BaseHTTPRequestHandler and only if the request is successfully parsed as HTTP.

New changeset 104fab0143e9 by Senthil Kumaran in branch '3.4':
Address issue 18229 - Explain http.server.BaseHTTPRequestHandler's .headers attribute further.
http://hg.python.org/cpython/rev/104fab0143e9