AAP-54476 : library.collectors - move collectors to library

[himdel]

Issue: AAP-54476

Move all collectors into metrics_utility.library.collectors. (Technically, copy, removing the originals is a second PR.)

A collector is a function decorated with @collector, it either returns a dict, or a list of csv filenames (from copy_table),
it always takes a db= parameter if it's supposed to talk to a db, or credentials for other services,
it never reads environment variables directly, always using params,
it takes since= and until= timestamp-with-timezone params if the collector supports collecting within time contraints, since is included (>=), until excluded (<),
it only takes args it uses, no extra **kwargs.

The @collector decorator wraps these into a class instance such that collector_fn(params).gather() actually calls the original collector_fn with params. This is to allow splitting collector config (which should happen outside of global tempdir handling) from actual gather (which should happen while holding a db lock).

Notes:

• output_dir= is needed for compatibility with the cli, but omitting it will work too (and create a new tempdir per collect)
• output_file= (unused but supported in copy_table) allows streaming the data without creating tempfiles - just writes to a filehandle object
• no cleanup happens for the collected files (except for the cleanup done by cli) - this will be the role of the library tempfile helper (wip, separate issue)

Controller collectors (metrics_utility.library.collectors.controller.*)

• config(db, billing_provider_params).gather() -> Dict
• execution_environments(db, [output_dir]).gather() -> [filenames]
• job_host_summary(db, since, until, [output_dir]).gather() -> [filenames]
• job_host_summary_service(db, since, until, [output_dir]).gather() -> [filenames]
• main_host(db, [output_dir]).gather() -> [filenames]
• main_indirectmanagednodeaudit(db, since, until, [output_dir]).gather() -> [filenames]
• main_jobevent(db, since, until, [output_dir]).gather() -> [filenames]
• main_jobevent_service(db, since, until, [output_dir]).gather() -> [filenames]
• unified_jobs(db, since, until, [output_dir]).gather() -> [filenames]

Other collectors (metrics_utility.library.collectors.others.*)

• total_workers_vcpu(cluster_name, metering_enabled, prometheus_url, ca_cert_path, token) -> Dict

---

Separate PR (#260):

The original collectors file retains all the collector functions, original decorators, any get_optional_collectors logic,
but otherwise the functions end up calling the library functions.

Later:

• move from f-strings to named query params - copy_table can handle it now; drop psycopg2, use safe sql
• why the extra backslash replace on event_data?

[sonarqubecloud]

Quality Gate passed

Issues
8 New issues
0 Accepted issues

Measures
0 Security Hotspots
91.1% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cshiels-ie]

LGTM 👍