RE: pg_createsubscriber does not check output_plugin_libraries

Dear Chao,

> That’s a fair point. The distinction I had in mind is that this patch explicitly adds a
> check for output_plugin_libraries to make --dry-run more useful. But when the
> caller cannot read that setting, pg_createsubscriber simply does not have enough
> information to perform the check. Would it make sense to print a warning in that
> case, rather than silently letting --dry-run succeed?

Hmm. IIUC there several three options;
1) raise WARNING, which is visible by default
2) raise INFO/DEBUG, which is visible with -v option
3) raise nothing.

But not sure which option is the best. Personally 1) might not be a good.
WARNINGs are reported with hints which the user can do. But in this case there
are no workarounds - to request changing a replication user is not suitable.

For now I'm not excited to print something at that time, any other thoughts?

Best regards,
Hayato Kuroda
FUJITSU LIMITED