rails PG::ConnectionBad (FATAL: role "" does not exist)

gistfile1.txt

// Likely you created a rails project with --database=postgresql

// If you haven't yet, setup a password for the postgres user, you can get into psql this way
$ sudo -u postgres psql

// Create the role
$ postgres=# CREATE ROLE <role> CREATEDB LOGIN PASSWORD 'password';
CREATE ROLE

// OR, if your user has been setup you can use the createuser util that comes with postgres

$ sudo -u postgres createuser -d -l -P <role>
Enter password for new role: 
Enter it again: 

// To check that your roles exist
$ sudo -u postgres psql
\dg

 Role name |                         Attributes                         | Member of 
-----------+------------------------------------------------------------+-----------
 <role>    | Create DB                                                  | {}
 postgres  | Superuser, Create role, Create DB, Replication, Bypass RLS | {}