Cleaning up name before appending unit on name

[knabben]

Unit append in the name were being removed when _total exists. This moves the clean up before appending the unit.

Refs #542

@brian-brazil Should this "repeated" unit raise an ValueError exception instead since this suffix is already append when dumping on WSGI.

[brian-brazil]

Can we also add a test that this is exposed correctly somewhere?

[knabben]

Added on tests/test_asgi.py and tests/test_wsgi.py

[brian-brazil]

Those are additional handlers, text_exposition would be the best place to put it.

[knabben]

PTAL

[brian-brazil]

Thanks!

[Sebadst]

Hello,

is this change intended?
I have just updated my prometheus-client from 0.7.1 to 0.8.0 and, as a result, all my metrics are broken.
Basically, if I had a metric like this:

JOBS = Counter(
    namespace=PROJECT,
    subsystem=ORCHESTRATOR,
    name="jobs",
    unit="total",
    documentation="Total number of jobs generated by the orchestrator.",
)

I was looking at it with the following:
sum(irate(project_orchestrator_jobs_total[5m])).
Now I need to do:
sum(irate(project_orchestrator_jobs_total_total[5m])).
It seems weird that such a change is from version 0.7.x to 0.8.x as it looks breaking.
Could you please let me know your thoughts on that?
Thank you.