Provide regex ID for API

[DL6ER]

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How familiar are you with the codebase?:

10

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See title. This was so far missing.

[DL6ER]

Rebased on latest development-v6

[yubiuser]

Why did you drop all the ttl stuff?

You're creating a new column in the database for the regex_id. So far, this was part of additional_info. Why did you change that? Do you plan to migrate the existing data from additional_info?

[DL6ER]

Why did you drop all the ttl stuff?

Pi-hole handles queries by "question" (a single domain) but TTL applies to replies and there may actually be multiple. Plus things get really difficult to disentangle when CNAMEs are there as well and even worse when a query is partially replied to from cache. This little extra bit of information is hard to get, not always unique and overall complicates code too much.

That's why I decided to drop it - this code was never used (it was commented out before).

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You're creating a new column in the database for the regex_id. So far, this was part of additional_info. Why did you change that? Do you plan to migrate the existing data from additional_info?

Yes, it is in additional_info but only most of the time not always. The information about the regex ID is actually lost when blocking happens during deep CNAME inspection because we then use additional_info to store the domains that actually led to blocking in this case. This issue can only be resolved when adding a new column. Fortunately, this will not affect the database size by much as empty columns take only one byte per row. Integers up to 127 use two bytes per row, integers up to 32767 take three bytes and so on. This seems affordable given that the database indices will typically be rather small here.

[yubiuser]

Needs documentation changes in https://deploy-preview-338--pihole-docs.netlify.app/database/ftl/

[DL6ER]

@yubiuser See pi-hole/docs#928

[yubiuser]

The information about the regex ID is actually lost when blocking happens during deep CNAME inspection because we then use additional_info to store the domains that actually led to blocking in this case. This issue can only be resolved when adding a new column.

Is this implemented with this PR as well?
I tried a quick check by setting up a local CNAME and used a deny regex to block the CNAME. It's not stored in the database nor shown in the web interface as blocked, but only as CNAME.
Or is this expected as it is a local CNAME not a CNAME from upstream?

Add:

Or is this expected as it is a local CNAME not a CNAME from upstream?

I just tested it: it's the same.