gevent 1.0.1: 500 error writing out Location header

[AM]

I have a small reduction case of the problem I am facing:

from gevent import monkey
monkey.patch_all()

from gevent.pywsgi import WSGIServer

def app(env, start_response):
start_response('302 Found', [('Location',
u'https://groups.google.com/forum/#!forum/gevent')])
return []

if __name__ == '__main__':
WSGIServer(('', 5000), app).serve_forever()


To run:

virtualenv _install
source _install/bin/activate
python <filename>.py

Hitting 127.0.0.1:5000 in a browser returns a 500.

The error traceback is:

Traceback (most recent call last):
File
"/work/bt/gevent-bug/_install/lib/python2.7/site-packages/gevent/pywsgi.py",
line 508, in handle_one_response
self.run_application()
File
"/work/bt/gevent-bug/_install/lib/python2.7/site-packages/gevent/pywsgi.py",
line 495, in run_application
self.process_result()
File
"/work/bt/gevent-bug/_install/lib/python2.7/site-packages/gevent/pywsgi.py",
line 488, in process_result
self.write('')
File
"/work/bt/gevent-bug/_install/lib/python2.7/site-packages/gevent/pywsgi.py",
line 380, in write
self._write_with_headers(data)
File
"/work/bt/gevent-bug/_install/lib/python2.7/site-packages/gevent/pywsgi.py",
line 391, in _write_with_headers
towrite.extend('%s: %s\r\n' % header)
TypeError: an integer or string of size 1 is required

Tracking it down in the code, it breaks here:
https://github.com/gevent/gevent/blob/1.0.1/gevent/pywsgi.py#L391

towrite.extend('HTTP/1.1 %s\r\n' % self.status)
for header in self.response_headers:
>> towrite.extend('%s: %s\r\n' % header)

Even if I were to encode the value of the location headers as utf-8 it
still fails.

Using pdb and walking through it, if I were to convert the input of
towrite.extend to a bytearray it will work, however iiuc it should not
be needed as such.

Any workarounds or help would be greatly appreciated.

TIA.
AM

[ams.fwd]

It appears bytearrays and unicode are not happy campers. Encoding the unicode header values makes it all go away.

Sigh! 2014 and we still cannot deal with unicode cleanly.

AM

[Nathan McCorkle]

I was running into the same issue, thinking it was the GET parameter query-string, but nope, it was the Response object creation code... I was following this example to send the user a HTML 'file' that I created on the fly (http://flask.pocoo.org/snippets/32/)... pasted here just-in-case:

strIO = StringIO.StringIO()
strIO.write('Hello from Dan Jacob and Stephane Wirtel !')
strIO.seek(0)

but in my case the string being passed to strIO.write() was a unicode string, which was causing the trouble.

The fix looked like this:

strIO = StringIO.StringIO()
now_not_unicode_string = unicode.encode(some_unicode_string)
strIO.write(now_not_unicode_string)
strIO.seek(0)