Best practices #264
Description
Metrics documentation lacks best practices section. API doc is good, but it is not obvious how you should use collectors and callbacks in real life.
For example, last time someone asked me about how to set up HTTP middleware I sent him to read my article since I wasn't be able to find a relevant example in documentation. How should one use callbacks in a role? What's the best way to create/delete a collector for specific object, if we use OOP in Lua? How to make your app resistant to metrics.clear()? We should find the answers to this questions and write them down, so customers' life may improve.