* Split RegisterAfterUpsert into two
We're going to need to be able to differentiate between Add and Update
for storing events in the _events table.
* Update mocks
* Support sorting on metadata.labels.NAME
The key to doing this is if we want to sort on, say, `metadata.labels.foo`, we need to
search for all rows with a label of the name `foo` in all the various
join tables we create for each label the query references.
We ignore nulls by giving them lowest priority using "NULLS LAST"
("NULLS FIRST" if sorting in descending order).
* Ensure labels that are mentioned only in sort params are still selected.
If we don't do this -- say we sort on metadata.labels.foo but never
make a test on it, the sort resuilts are ignored.
* Remove extraneous debugger statements.
Previous SQLite-related code used context.Background() and context.TODO() because it was not developed with context awareness.
This commit propagates the main Steve context so that it can be used when interacting with SQL context-aware functions.
This PR removes all production-code use of context.Background() and context.TODO() and replaces test-code use of TODO with Background.
Contributes to rancher/rancher#47825
This introduces the a `WithTransaction` function, which is then used for all transactional work in Steve.
Because `WithTransaction` takes care of all `Begin`s, `Commit`s and `Rollback`s, it eliminates the problem where forgotten open transactions can block all other operations (with long stalling and `SQLITE_BUSY` errors).
This also:
- merges together the disparate `DBClient` interfaces in one only `db.Client` interface with one unexported non-test implementation. I found this much easier to follow
- refactors the transaction package in order to make it as minimal as possible, and as close to the wrapped `sql.Tx` and `sql.Stmt` functions as possible, in order to reduce cognitive load when working with this part of the codebase
- simplifies tests accordingly
- adds a couple of known files to `.gitignore`
Credits to @tomleb for suggesting the approach: https://github.com/rancher/lasso/pull/121#pullrequestreview-2515872507
