Configuration
=============
:py:mod:`sprockets-postgres <sprockets_postgres>` is configured via environment variables. The following table
details the configuration options and their defaults.

+---------------------------------+--------------------------------------------------+-----------+
| Variable                        | Definition                                       | Default   |
+=================================+==================================================+===========+
| ``POSTGRES_URL``                | The PostgreSQL URL to connect to                 |           |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_MAX_POOL_SIZE``      | Maximum connection count to Postgres per backend | ``10``    |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_MIN_POOL_SIZE``      | Minimum or starting pool size.                   | ``1``     |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_CONNECTION_TIMEOUT`` | The maximum time in seconds to spend attempting  | ``10``    |
|                                 | to create a new connection.                      |           |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_CONNECTION_TTL``     | Time-to-life in seconds for a pooled connection. | ``300``   |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_QUERY_TIMEOUT``      | Maximum execution time for a query in seconds.   | ``60``    |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_HSTORE``             | Enable HSTORE support in the client.             | ``FALSE`` |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_JSON``               | Enable JSON support in the client.               | ``FALSE`` |
+---------------------------------+--------------------------------------------------+-----------+
| ``POSTGRES_UUID``               | Enable UUID support in the client.               | ``TRUE``  |
+---------------------------------+--------------------------------------------------+-----------+

If ``POSTGRES_URL`` uses a scheme of ``postgresql+srv``, a SRV DNS lookup will be
performed and the URL will be constructed containing all host and port combinations
in priority and weighted order, utilizing `libpq's supoprt <https://www.postgresql.org/docs/12/libpq-connect.html>`_
for multiple hosts in a URL.

AWS's ECS service discovery does not follow the SRV standard, but creates SRV
records. If ``POSTGRES_URL`` uses a scheme of ``aws+srv``, a SRV DNS lookup will be
performed using the correct format for ECS service discovery.