Make ignore_metrics support * wildcard for OpenMetrics

[ahmed-mez]

What does this PR do?

• Metrics can be ignored if they match afnmatchcase pattern
• Document the ignore_metrics openmetrics check parameter

Motivation

More flexible config to ignore metrics

Additional Notes

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• PR title must be written as a CHANGELOG entry (see why)
• Files changes must correspond to the primary purpose of the PR as described in the title (small unrelated changes should have their own PR)
• PR must have changelog/ and integration/ labels attached

[L3n41c]

Can’t we use sets rather than dictionnary ?
It seems that the only value that we use is True and we only check for element existence.

Suggested change

	config['_ignored_metrics'] = {}
	config['_ignored_patterns'] = {}
	# Separate ignored metric names and ignored patterns in different maps for faster lookup later
	for metric in config['ignore_metrics']:
	if '*' in metric:
	config['_ignored_patterns'][metric] = True
	else:
	config['_ignored_metrics'][metric] = True
	config['_ignored_metrics'] = set()
	config['_ignored_patterns'] = set()
	# Separate ignored metric names and ignored patterns in different maps for faster lookup later
	for metric in config['ignore_metrics']:
	if '*' in metric:
	config['_ignored_patterns'].add(metric)
	else:
	config['_ignored_metrics'].add(metric)

[ahmed-mez]

indeed thanks!

[ofek]

This will cause a large slow down. No way around it I guess, just saying...

[mfpierre]

is it worth adding a if config['ignore_metrics'] or the for on the empty set if fast enough?

[ahmed-mez]

here is a small benchmark - it's almost the same

>>> timeit('for x in s:    print("found")', setup='s = set(); x = "randomstring"',number=100000)
0.004889011383056641
>>>
>>> timeit('if map:    print("found")', setup='map = dict()', number=100000)
0.003404855728149414

[mfpierre]

in absolute it's fast yes, but looks like we could use the 30% speedup 👍

[ahmed-mez]

here is a follow-up PR #5764