Postgres connection - add option to set user "role"

[Kartikeya-Tiwari]

Is your feature request related to a problem? Please describe.
I am trying to connect my Postgres instance to Cube Core - however our instance is set in a way where in addition to providing Username and Password we also need to provide a user role (https://www.postgresql.org/docs/current/sql-set-role.html)

Based on my research seems like Cube currently does not support this.

It would be great if we could support this as an optional configuration option just like dbt (https://docs.getdbt.com/docs/core/connect-data-platform/postgres-setup)

Describe the solution you'd like
It would be great if we could have an environment variable to set user role, just like the ones we have for username and password.
Also, @igorlukanin suggested another option on slack that - we could achieve this via "initSql" config option, just like for it is done in DuckDB

cube/packages/cubejs-duckdb-driver/src/DuckDBDriver.ts

Lines 163 to 173 in 34d319a

	if (this.config.initSql) {
	try {
	await execAsync(this.config.initSql);
	} catch (e) {
	if (this.logger) {
	console.error('DuckDB - error on init sql (skipping)', {
	e
	});
	}
	}
	}

Thanks

[github-actions]

If you are interested in working on this issue, please go ahead and provide PR for that.
We'd be happy to review it and merge it.
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[igorlukanin]

Also, @igorlukanin suggested another option on slack that - we could achieve this via "initSql" config option, just like for it is done in DuckDB

I actually believe it would be great to have initSql for any data source driver! I wonder if anyone is open to contributing this 😄