Dovecot version : 2.3.x - using RedHat build

Years ago I had a Dovecot install that was setup to perform certificate based authentication for clients that worked well - part of that setup was creating a passdb that pointed to a flat file that contained entries like this:

cool.joe.c:{PLAIN}::::::username=cooljc

and the passdb definition looked like this:

passdb { driver = passwd-file args = scheme=plain /etc/dovecot/users.external skip = authenticated mechanisms = EXTERNAL default_fields = uid=vmail gid=vmail nopassword=1 }

That worked and we had a cron job that would build that users.external file and keep it up to date.

Now, a few years down the road, I've setup a new Dovecot server that is working wonderfully but I'd like to add the same functionality but also use a direct LDAP query instead of managing a flat file to maintain the list of users.

I have another passdb entry that is using LDAP that works great for username/password auth, but I'd like to test what I think is a proper LDAP configuration specific for this passdb,

But for the life of me I can't find out how to test the configuration file without having to actually update my dovecot configuration to use it. I'm looking for something like the Postfix 'postmap' tool that I can provide my configuration file for the LDAP lookup, give a username input to and it will show me the results from the configuration, including the return values.

Is there such a tool ? Or do I have to setup a test server, add it to the config, and debug it ? Sorry if this is FAQ or dumb question - I've been reading documentation on the official Dovecot site looking for the answer but I'm either missing it or I'm reading the wrong docs.