Add experimental Docker log follower implementation

[tjb346]

I saw this issue was marked as help wanted here https://github.com/martin-helmich/prometheus-nginxlog-exporter/issues/67 and decided to take a stab at it since I need this feature too.

The instructions on how to use are in the README, but basically you enable experimental features, mount the host's docker socket to the container, and add the following to the config:

namespace "nginx" {
  source {
    docker {
      container = "nginx_container_name"
    }

    // ...
  }
}

[qlty-cloud-legacy[bot]]

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[martin-helmich]

Oh, wow. 😍 Thanks for the contribution. 👍 I'll take a look shortly.

[selckin]

Tried to use this with https://github.com/nginx-proxy/nginx-proxy, but nginx-proxy prepends "nginx.1 |" to the log messages, don't see a way configure the 'format' to include/ignore those, would love to hear if it i possible

[helmich-bot]

There has not been any activity to this pull request in the last 30 days. It will automatically be closed after 7 more days. Remove the stale label to prevent this.

[zidagar]

I've tested this feature and works correctly. Do you think to reopen the pull request and merge it in the next release?

[jasenmh]

I could use this as well. Is there any other interest in re-opening this PR?

[martin-helmich]

Re-opening for now. I still remember wanting to test some edge cases on this, but then I lost track of this one... I'll give it another look shortly.

[helmich-bot]

There has not been any activity to this pull request in the last 30 days. It will automatically be closed after 7 more days. Remove the stale label to prevent this.

[helmich-bot]

There has not been any activity to this pull request in the last 30 days. It will automatically be closed after 7 more days. Remove the stale label to prevent this.

[giom-l]

This would be extremely helpful ! Any chance to have it reviewed & merged soon ?