Configurable Data Plane Log Format

[mpstefan]

As a user of NGF
I want to have the ability to configure the log format of NGINX's access and error logs
So that I can easily collect logs from NGINX in my logging platform.

Acceptance

• NGINX's access and error logs' format can be configured during runtime via a CRD as according to NGINX's existing specifications.

[kiyutink]

Hey, is there a workaround to configure logging right now? e.g. I want to log a specific header for each request, is there a way to achieve this?

[bjee19]

Hey @kiyutink, the current workaround to configuring logging would be using SnippetsFilters, which allow you to insert nginx configuration into the configuration that NGF generates. Here's a guide on using them https://docs.nginx.com/nginx-gateway-fabric/how-to/traffic-management/snippets/.

You would then be able to add and configure the nginx directives log_format and access_log to your liking. You should be able to accomplish what you want by using log_format at the http level and access_log at the server level. Here's another guide on configuring logging that I found which might be helpful https://docs.nginx.com/nginx/admin-guide/monitoring/logging/.

Hopefully you can play around with the nginx configuration to get it to work!

[kiyutink]

Hey @bjee19 , thank you for the detailed reply. Just one thing - is it possible to reference the SnippetsFilter not from a route resource? Ideally, I would like to be able to set one default log format for all routes, without explicitly referencing that format in each HTTPRoute. I understand, that I could set the access_log directive in the server context, for example, but in order to do that I still have to pick one route that will reference the SnippetsFilter.

The best thing I could think of is using a "fake" route that never matches but adds a filter, but perhaps there's something less "hacky"?

[bjee19]

@kiyutink Unfortunately it is not currently possible to reference the SnippetsFilter a resource that is not a route.

Ideally in situations like this, we'd have completed the above story hahaha, but since we haven't, SnippetsFilters are the only means to solve this situation and are meant to kind of be a last resort hack job. SnippetsFilters and snippets are designed to be small insertions of configuration into specific areas, so it unfortunately makes sense for it to feel hacky when trying to insert configuration which affects large areas.

Best choice is to either see if that "fake" route works, or just switching the SnippetsFilters between stable routes, which shouldn't be too much of an issue unless you're moving around routes frequently. Sorry that its not the best options, but hopefully once this story gets completed there will be a better option!