feat(config): Allow setting log format from envar

[szechyjs]

There is a large discontinuity between config values that can be set in environment variables. When running in containers the prefered config approach is through environment variables and not config files. This PR enables setting of the logging format through an environment variable

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[Dav1dde]

@szechyjs thanks for the PR, I went ahead and fixed a small issue with a missing cli arg and added a changelog entry.

I also found that --log-level does not work when passed via cli (it does via env var)... Something to investigate separetely.

[Dav1dde]

Gonna merge tomorrow, wanna check CI first and I am hungry now^^.

[szechyjs]

@szechyjs thanks for the PR, I went ahead and fixed a small issue with a missing cli arg and added a changelog entry.

I also found that --log-level does not work when passed via cli (it does via env var)... Something to investigate separetely.

Yea I noticed the same, I originally implemented the cli arg and it didn't work, so removed it. Glad it's an existing issue.

[Dav1dde]

Yea I noticed the same, I originally implemented the cli arg and it didn't work, so removed it.

Because of this change:

relay/relay/src/cli.rs

Line 84 in bd0cfaa

log_format: matches.get_one("log_format").cloned(),

it must be still exposed via CLI.

I suspect it's just an order problem, we initialize logging before applying CLI ovverides.