Question

I’m searching a wsgi middleware which I can warp around a wsgi applications and which lets me monitor incoming and outgoing http requests and header fields.

Something like firefox live headers, but for the server side.

Answer 1

The middleware

from wsgiref.util import request_uri import sys  def logging_middleware(application, stream=sys.stdout):     def _logger(environ, start_response):         stream.write('REQUEST\n')         stream.write('%s %s\n' %(             environ['REQUEST_METHOD'],             request_uri(environ),         ))          for name, value in environ.items():             if name.startswith('HTTP_'):                 stream.write('    %s: %s\n' %(                     name[5:].title().replace('_', '-'),                     value,                 ))         stream.flush()         def _start_response(code, headers):             stream.write('RESPONSE\n')             stream.write('%s\n' % code)             for data in headers:                 stream.write('    %s: %s\n' % data)             stream.flush()             start_response(code, headers)         return application(environ, _start_response)     return _logger 

The test

def application(environ, start_response):     start_response('200 OK', [         ('Content-Type', 'text/html')     ])     return ['Hello World']  if __name__ == '__main__':     logger = logging_middleware(application)     from wsgiref.simple_server import make_server     httpd = make_server('', 1234, logger)     httpd.serve_forever() 

See also the werkzeug debugger Armin wrote, it’s usefull for interactive debugging.