postgresql mockup to reproduce different system scenarios

Create a daemon that simulate postgresql server for a set of queries served over unix-socket by netcat, here an example:

 mockpg.py -t 5 \
        "SELECT setting FROM pg_settings WHERE name = 'standard_conforming_strings';" '[ [ "setting" ], [ "off" ], ]' \
        "SELECT setting FROM pg_settings WHERE name = 'listen_addresses';" '[ [ "setting" ], [ "localhost" ], ]' \
        "SELECT setting FROM pg_settings WHERE name = 'max_connections';" '[ [ "setting" ], [ "100" ] ]' \
        "SELECT setting FROM pg_settings WHERE name = 'max_locks_per_transaction';" '[ [ "setting" ], [ "64" ] ]' \
        "SELECT setting FROM pg_settings WHERE name = 'max_prepared_transactions';" '[ [ "setting" ], [ "0" ] ]'

where:
   -t <sec> specify an inactivity timeout. after the application exit
   each couple of parameters is "<query>" "[ [ <field1_desc>, <field2_desc>, ...], [ <field1_value1>, <field2_value1>, ...], [ <field1_value2>, <field2_value2>], ... ]"