Port collision with primary webserver process

[brian-lc]

Hello, I was wondering about the decision to include PORT as the default here. My understanding might be wrong but if I have a webserver like Unicorn or Puma I probably have 'PORT' defined in my environment already. When starting the metrics server from my Unicorn process (for example) the metrics server would fail to start due to port collision with the already running unicorn. So I pretty much have to define 'PROMETHEUS_EXPORTER_PORT=9394' even if I'm okay with the default port number.

I'm happy to write up a PR for this change but thought I'd ask about the usage or thoughts behind this line of code first.

Thanks much! Really appreciate this project and your work!

yabeda-prometheus-mmap/lib/yabeda/prometheus/mmap/exporter.rb

Line 25 in 5edb9f1

default_port = ENV.fetch('PORT', 9394)

[Envek]

Hey and sorry for the late response.

In case of web servers, you can use web server itself to expose metrics on different port. For Puma there is built-in support in yabeda-puma-plugin, see Exposing metrics on a different port section in its README.