[YSQL] LDAP Integration for YugabyteDB

[AmirAbrams]

Jira Link: DB-2197
Support LDAP authorization and authentication.

YSQL

For YSQL, this would be similar to the PostgreSQL LDAP authentication support. This is tracked in #6088

YCQL

Similar to YSQL, LDAP should also be supported for YCQL. This is tracked in #4421

[ajcaldera1]

On which API are you seeking this support - YCQL or YSQL?

[AmirAbrams]

YSQL. Thanks again.

[ajcaldera1]

We haven't formally tested it yet, but it should be enabled already. We re-use the top 80% of the PG distribution in our code, so postmaster should work out of the box. To pass the pg_hba.conf settings you need for LDAP, use the flag --ysql_hba_conf="<comma separated list of pg_hba.conf entries>" on your yb-tserver invocation either on the command line or in the flag file as documented.
We are based on PG 11.2, so use the appropriate docs for that release. If you could, please reply to this thread with your results, positive or negative.
Thanks.