Path type RegularExpression matcher

[jefimm]

It looks like RegularExpression path matcher requires RE2 type of regular expressions while nginx supports PCRE.
This discrepancy hinders migration from the nginx-ingress where the PCRE syntax was accepted.
Why does the gateway enforce additional constrains ?

[nginx-bot]

Hi @jefimm! Welcome to the project! 🎉

Thanks for opening this issue!
Be sure to check out our Contributing Guidelines and the Issue Lifecycle while you wait for someone on the team to take a look at this.

[salonichf5]

Thank you for your interest in NGINX Gateway Fabric.

In NGF, RegularExpression path matches follow and use RE2 syntax rather than full PCRE. The controller is written in Go and relies on Go’s regexp (RE2) engine, which is chosen for safety (no catastrophic backtracking / ReDoS). Is there a way those can be translated to RE2?

[jefimm]

With nginx ingress I was able to route requests to my service using following pattern ( everything excluding /service/private)
/(service\/(?!private/).*)
with gateway fabric this is no longer possible

[jonathanribas]

Same for /rest/.*/V1/order/get/.*.
Hope we will have more flexibility anytime soon.

[salonichf5]

We have prioritized this issue for next release 2.3 to make the regex NGINX friendly.