Dealing with parser requires the following steps:

1. Add custom log format to the nginx.conf's http section

   log_format my_log_format '$msec|$cookie_id|$uri|$status|$request_time|$request_length';

2. Specify my_log_format as desired format for your access.log

   access_log /var/log/nginx/futuritest-access.log my_log_format buffer=32k;

3. Create virtualenv

   virtualenv ~/env/

4. Install required python dependencies

   pip install -r requirements.txt

5. Run fake webserver (this webserver responds with random content for any dispatched url)

   python application.py

6. Run log monitor itself providing path to access.log file, and, optionally, mongo database and collection names

   python logmonitor.py /var/log/nginx/futuritest-access.log --database=test --collection=logs

7. Generate fake traffic with send_requests.py

   python send_requests.py http://localhost/

8. In order to force log rotation

   sudo logrotate /etc/logrotate.d/nginx -vf

Since task is pretty trivial, there is no much to justify, really.

MongoDB was chosen since it has rich query language which can potentially allow any further logs analysis, write speed is high enough, and if not, write sharding is supported out of box for easy horizontal scaling. Long story short, it's good enough for our purposes.