Crashes after upload

[tsjnachos117]

As soon as I download a file, this server crashes. The file uploads just fine, and the program keeps running, so I can upload/download more files, but when I get a "Connection was reset" error in my browser, it's easy to assume the upload failed.

Here's the terminal output with python3:

server_version: simple_http_server/0.3.1, python_version: Python/3.8.10
sys encoding: utf-8
Serving http on: 0.0.0.0, port: 8000 ... (http://0.0.0.0:8000/)
True File '/dev/shm/simple_http_server/test_file' upload success! by:  ('127.0.0.1', 55798)
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 55798)
Traceback (most recent call last):
  File "/usr/lib/python3.8/socketserver.py", line 316, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/lib/python3.8/socketserver.py", line 347, in process_request
    self.finish_request(request, client_address)
  File "/usr/lib/python3.8/socketserver.py", line 360, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/lib/python3.8/socketserver.py", line 747, in __init__
    self.handle()
  File "/usr/lib/python3.8/http/server.py", line 427, in handle
    self.handle_one_request()
  File "/usr/lib/python3.8/http/server.py", line 415, in handle_one_request
    method()
  File "simple_http_server.py", line 82, in do_POST
    f.write(b"<br><a href=\"%s\">back</a>" % self.headers['referer'].encode('utf-8'))
AttributeError: 'NoneType' object has no attribute 'encode'
----------------------------------------
^CYou chose to stop me.

And Here's the python2 output:

server_version: simple_http_server/0.3.1, python_version: Python/2.7.18
sys encoding: utf-8
Serving http on: 0.0.0.0, port: 8000 ... (http://0.0.0.0:8000/)
(True, u"File '/dev/shm/test_file' upload success!", 'by: ', ('127.0.0.1', 55800))
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 55800)
Traceback (most recent call last):
  File "/usr/lib/python2.7/SocketServer.py", line 293, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/lib/python2.7/SocketServer.py", line 321, in process_request
    self.finish_request(request, client_address)
  File "/usr/lib/python2.7/SocketServer.py", line 334, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/lib/python2.7/SocketServer.py", line 655, in __init__
    self.handle()
  File "/usr/lib/python2.7/BaseHTTPServer.py", line 340, in handle
    self.handle_one_request()
  File "/usr/lib/python2.7/BaseHTTPServer.py", line 328, in handle_one_request
    method()
  File "simple_http_server.py", line 82, in do_POST
    f.write(b"<br><a href=\"%s\">back</a>" % self.headers['referer'].encode('utf-8'))
  File "/usr/lib/python2.7/rfc822.py", line 393, in __getitem__
    return self.dict[name.lower()]
KeyError: 'referer'
----------------------------------------
^CYou choose to stop me.

[tsjnachos117]

I think I figured it out. My browser is set to never give a referal header (because privacy). So, this server was trying to convert an empty string into binary, which doesn't work.

To work around this issue, I changed line 82 (in simple-http-server.py) to:

        f.write((b"<br><a href=\".\">Back</a>").encode('utf-8'))

And that seems to have worked! When you have a hyperlink that points to ., that's a quick and easy way to reload the current page, without needing any POST data. It's basically a relative path to "wherever you already are". The above code also ignores your referal header, so it's not an issue anymore.

Tested with python versions 2.7.18 and 3.8.10

[freelamb]

add PR

[tsjnachos117]

I will make a PR. But first, I'd like to point out that my above code doesn't seem to work on Python3. I guess *.encode commands don't work well with string that start with an unquoted b. Here are two pieces of code that seem to work better:

Option 1:

    f.write(b"<br><a href=\".\">Back</a>")

Option 2:

    f.write(("<br><a href=\".\">Back</a>").encode('utf-8'))

I have no idea which is better. If someone who knows more about Python than I do could weigh in, that'd be great. Maybe it makes no difference?

[tsjnachos117]

Since no one has weighed in, I've decided to make a PR with the shorter one. That seems to work well enough. If you choose to accept the PR, feel free to close this report.