PostgreSQL versions lower than 11 come bundled with chkpass extension for storing encrypted passwords. This was removed from Postgres 11 and later. This is a stand alone version for use with those.
Install appropriate Postgres server development package
apt-get install postgresql-server-dev-12
To build and install this module:
make
make install
make install installcheck
or selecting a specific PostgreSQL installation:
make PG_CONFIG=/some/where/bin/pg_config
make PG_CONFIG=/some/where/bin/pg_config install
make PG_CONFIG=/some/where/bin/pg_config installcheck
make PGPORT=5432 PG_CONFIG=/usr/lib/postgresql/12/bin/pg_config clean install installcheck
Make sure you set the connection parameters like PGPORT right for testing.
And finally inside the database:
CREATE EXTENSION chkpass;