AssertionError: Headers already set! Status: 500 Internal Server

[Jaiky]

learning web concpt in python


wrote code in /usr/lib/cgi-bin/hello_world.py

###########################################################################
#!/usr/bin/env python

import webapp2


form ="""
<form action="http://www/google.com/search">
<input name="q">
<input type="submit">
</form>"""


class MainPage(webapp2.RequestHandler):
def get(self):
self.response.out.write(form)



class TestHandler(webapp2.RequestHandler):
def get(self):
q=self.request.get("q")
self.response.out.write(q)

apps = webapp2.WSGIApplication([('/', MainPage),('/testform',TestHandler)],debug=True)


def main():
apps.run()


if __name__ == '__main__':
main()


###############################################################################

when running this code on ubuntu 12.04 using command

python hello_world.py

error obtained


AssertionError: Headers already set!
Status: 500 Internal Server Error
Content-Type: text/plain
Content-Length: 59


##########################################################################

want help please urgent ....................

 

[Terry Reedy]

learning web concpt in python
wrote code in /usr/lib/cgi-bin/hello_world.py

###########################################################################
#!/usr/bin/env python

import webapp2

This is an external package.

form ="""
<form action="http://www/google.com/search">
<input name="q">
<input type="submit">
</form>"""

class MainPage(webapp2.RequestHandler):
def get(self):
self.response.out.write(form)

class TestHandler(webapp2.RequestHandler):
def get(self):
q=self.request.get("q")
self.response.out.write(q)

apps = webapp2.WSGIApplication([('/', MainPage),('/testform',TestHandler)],debug=True)

def main():
apps.run()

if __name__ == '__main__':
main()
###############################################################################

when running this code on ubuntu 12.04 using command

python hello_world.py

error obtained

AssertionError: Headers already set!

This all comes from webapp2. You should never see assertion error.
Report to authors or ask on webapp2 mailing list if there is one.

Status: 500 Internal Server Error
Content-Type: text/plain
Content-Length: 59

You should have made subject line something like
"Webapp2: AssertionError"
as only someone familiar with webapp2 could give you any help.