Moving from connection_error_total to connection_total metric

[ppatierno]

Currently, the connection_error_total metric is exposed and it tracks the total number of errors when testing the connection to the brokers.
Anyway, this metric has a "connected" label which is always set to false but it doesn't make any sense this way because the metric itself is clearly about errors.
The purpose of the metric was to reporting the total number of connections, successfully or not, by using the "connected" label with true or false value.
For this reason, the metric name was a mistake and it doesn't reflect successful connections (which are anyway not tracked, unless the latency ones).
Said that it would be better changing this metric to connection_total and using the "connected" label the right way to distinguish between success and failure on connection.
To avoid breaking changes, I would deprecate the connection_error_total in the first coming version (0.2.0) while adding the new one connection_total and then removing the error one in the next version (0.3.0?).

[ppatierno]

What I proposed wasn't done in time for 0.2.0 so at this point the plan is delayed.
The connection_error_total will be deprecated in the 0.3.0 while adding the new one connection_total and then removing the error one in the next version (0.4.0?).
FYI @k-wall

[robobario]

Hi @ppatierno, is this issue dead?

[ppatierno]

@robobario no I don't think so, you can work on it if you want. Of course the plan is delayed again so I would deprecate in the next 0.7.0 while adding the new one and removing the old one in 0.8.0.

[robobario]

Thanks @ppatierno, I was just checking up since we had a ticket to react. I've pushed up a PR to deprecate the old and start emitting the new metric.