Question about breaking changes introduced in #343

[ogxd]

Hello 👋

#343 introduced breaking changes over IMetricFactory methods due to the addition of the timeToLive argument. By making this new argument optional, I thought foolishly it would make theses methods backward compatible in the cases where the user did not use these optional arguments. It does work in a solution where Prometheus.Client is a direct dependency, however, the new argument makes the method signature different, even though the argument is optional. As a consequence, when trying to reintegrate a package built from the current master into a project that had Prometheus.Client already as a transitive dependency, I get such runtime errors:

System.MissingMethodException : Method not found: 'Prometheus.Client.IMetricFamily`2<Prometheus.Client.IGauge,!!0> Prometheus.Client.IMetricFactory.CreateGauge(System.String, System.String, !!0, Boolean)'.
            A ------references------> B
            |                         |
            |                         |
Prometheus.Client v6       Prometheus.Client v5

Of course, a fix is to update Prometheus.Client to v6 in B, but that can be annoying consuming for users, especially where they have no code to change, but just to update Prometheus.Client.

The update to v6 should be smoother if we had kept the CreateXXXXX() methods without the timeToLive argument (on top of thoses with the timeToLive argument). The downside however is that the number of methods in IMetricFactory is already quite substantial, and that would easily add 50% more methods to it.

What are you thoughts?

[phnx47]

We will force update users of Prometheus.Client.AspNetCore and Prometheus.Client.MetricServer, but for other packages, I expect to maintain compatibility.

Keep the current CreateXXXXX() methods without the timeToLive parameter, and add new overloads that include timeToLive.

To improve file readability, consider marking the MetricServer class as partial and splitting it into multiple files:

MetricFactory.cs
MetricFactory.CreateCounter.cs
MetricFactory.CreateGauge.cs
MetricFactory.*.cs

[ogxd]

Thanks @phnx47, I'll do this