ingress path case-insensitive issue with haproxy-controller

[mustafasemihbay]

Hello,

We are currently migrating ingress controller from ingress-nginx to haproxy-ingress and encountered an issue related to case-sensitive path matching.

In ingress-nginx, path matching works in a case-insensitive manner. For example, when the path is configured as /example-api, it correctly matches URLs such as /example-api, /EXAMPLE-api, or /example-Api. However, with haproxy-ingress we receive a 404 Not Found error when the case differs.

We tested different pathType options (ImplementationSpecific, Exact, and Prefix), but the behavior did not change. Case-insensitive path matching is important for us during this migration. It may also be relevant for other users migrating from ingress-nginx.

Environment;
Azure Kubernetes Service(v1.34.1)
haproxy-ingress deployed with Helm v1.48.0 (App Version v3.2.5).

basically ingress rule like this;

spec:
rules:
- host: example.domain.com
http:
paths:
- path: /example-api
pathType: ImplementationSpecific
backend:
service:
name: example-api
port:
number: 80

[mustafasemihbay]

Hi, I added optional case-insensitive path matching support and created PR -> #798

[maharshi9c]

We got same issue

Description

HAProxy Kubernetes Ingress Controller (v3.2.5, Helm chart 1.48.0) performs case-sensitive path matching with no working workaround available in the current release.

The problem

Ingress paths stored in path-prefix.map and path-exact.map are matched case-sensitively against incoming request paths. When a client sends a path that differs only in case from the defined ingress path, HAProxy returns HTTP 404 even though the path logically matches.

Example:

• Ingress defines: /api/ForgotUsernamePassword/validate-credentials
• Client sends: /api/forgotUsernamePassword/validate-credentials
• Result: HTTP 404 — no match in the map

This broke a production service after migration from Nginx (which matches paths case-insensitively by default).

---

Expected Behaviour

One of the following should work:

1. Inline (?i) regex flag in the ingress path should enable case-insensitive matching for that path, e.g.:

   paths:
     - path: /(?i)api/ForgotUsernamePassword/.*
       pathType: ImplementationSpecific