track_req_resp_wsgi.py

# Original WSGI application.

def application(environ, start_response):
    ...

# Logging WSGI middleware.

import pprint

class LoggingMiddleware:

    def __init__(self, application):
        self.__application = application

    def __call__(self, environ, start_response):
        errors = environ['wsgi.errors']
        pprint.pprint(('REQUEST', environ), stream=errors)

        def _start_response(status, headers):
            pprint.pprint(('RESPONSE', status, headers), stream=errors)
            return start_response(status, headers)

        return self.__application(environ, _start_response)

application = LoggingMiddleware(application)