Adding call_id, from and to labels to loki logs

[htmluz]

Building a backend that had a ton of logs with Homer and Loki required adding those labels for performance purposes. Better query times by those labels. Added to rtcp to so it could correlate all call packets with one search by cid.

[CLAassistant]

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[lmangani]

Thanks for taking the time and submitting a PR - we appreciate it! Could you please document the PR with some examples to confirm if the code matches the presented change? And while this might solve an issue it also creates a much bigger one as unfortunately the new labels would introduce high cardinality and its definitely not suitable for all users/setups.

At the very least we need to add a parameter to control the behaviour (like we already do for the IP tags)

[htmluz]

Ok I actually hadn't thought about that and am not sure if it will be useful to have the option. After your comment I figured out it's more of a personal need to me to have it since I use a completely different backend to view the calls and then fetch the data from loki, btw I've added the option defaulting to false, in case it fits. thx for your time

[lmangani]

@htmluz we also use a different backend (qryn/gigapipe) but its always best to be aware of high-cardinality fields particularly for those who might not use this feature. I think it would be even nicer to generalize this and allow any of our extracted fields to be paired with a label in HOMER11