Variable context support

[mskyttner]

The httpserver not seems to be aware of variables that were set (in the session?), returning NULLs.

An example use case where this would be handy is when you'd like to run a cronjob (using that extension) inside a running httpserver instance regularly (for example to update a table daily which is then served over the httpserver API.

The goal would to be able to have a statement like running:

select cron('create or replace table hr_today as (from read_csv_auto(getvariable(''hr_today_filepath'')))', '0 0 0 8 * *');

Could it be that when httpserver starts, some process or thread is forked and the variables set when the server starts (in an init.sql script) is not "brought along" and therefore lost? Currently it seems variables that are set are blanked out when the server is running and just return NULL.

Perhaps some change similar to Query-farm/cronjob@5eed5fd might be able to alleviate this?

[lmangani]

Thanks @mskyttner you're right about both limitation and solution. Feel free to submit a PR and take credit 😉 if that's not possible we'll add this to the list and patch as soon as time allows