Process Exporter added: provide num of processes with pattern 'chia p…

[schmiddim]

Hi,
I've made some minor improvments:

Process Exporter added: provide num of processes with pattern 'chia plot create' as a metric namedprocess_namegroup_thread_count to see how many plots are in creation.

Created volume mounts for Prometheus and Promtrail: makes it easy to modify the config files. Just restart docker-compose to apply changes instead of deleting the images.

docker-compose.yml: Version bump to remove Linter errors (You are already on v3 of docker-compose syntax).

[retzkek]

Thanks for the PR! Personally I prefer baking baking config files into the images, especially for dev/demo environments (I realize that many people are using this as-is though). The process exporter sounds interesting, I'll look it over.

[frosty5689]

I get the intent is to provide a POC for others to follow and get to a customized setup tailored to each individual's needs, but people without DevOps experience and security awareness will run the docker-compose as is and it can potentially be a security concern if one of those containers have a vulnerability with the container running under host network it can compromise the user's network easily. It is great that the node-exporter mounts / as readonly, IMO the other mounts to logs and certificates should also be readonly as there is no need to write to them from the container itself. Just my two cents.

[retzkek]

@frosty5689 This would be better in a new issue (although thanks for reminding me of this PR). Host networking is used because it's the simplest way to get a working setup on linux (chia_exporter needs to talk to the Chia API running on the host). If you'd like to propose some changes to improve security without significantly affecting usability (some entrypoint scripts could probably go a long way) I'd be happy to consider your changes.