Add regex matching for headers and query params for HTTPRoute and GRPCRoute

[salonichf5]

Proposed changes

Write a clear and concise description that helps reviewers understand the purpose and impact of your changes. Use the
following format:

Problem: Users want to be able to specify RegularExpression as headers and query params type.

Solution: Adds functionality to add RegularExpression type for headers in HTTPRoutes and GRPCRoutes and query params in HTTPRoutes.

Testing: Manual Testing

For HTTPRoutes, manual testing done using Advanced Routing examples

This route configures headers and query params with regex matching for coffee-v3 svc. If the regex match succeeds we receive a response from coffee-v3 svc , otherwise all request are responded by coffee-v1

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: coffee
spec:
  parentRefs:
  - name: cafe
  hostnames:
  - cafe.example.com
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /coffee
    backendRefs:
    - name: coffee-v1-svc
      port: 80
  - matches:
    - path:
        type: PathPrefix
        value: /coffee
      headers:
      - name: version
        value: v2
    - path:
        type: PathPrefix
        value: /coffee
      queryParams:
      - name: TEST
        value: v2
    backendRefs:
    - name: coffee-v2-svc
      port: 80
  - matches:
    - path:
        type: PathPrefix
        value: /coffee
      headers:
      - name: headerRegex
        type: RegularExpression
        value: "header-[a-z]{1}"
    - path:
        type: PathPrefix
        value: /coffee
      queryParams:
      - name: queryRegex
        type: RegularExpression
        value: "query-[a-z]{1}"
    backendRefs:
    - name: coffee-v3-svc
      port: 80

Matches the regular expression, responds from coffee-v3

curl --resolve cafe.example.com:$GW_PORT:$GW_IP http://cafe.example.com:$GW_PORT/coffee -H "headerRegex:header-a"
Handling connection for 8080
Server address: 10.244.0.111:8080
Server name: coffee-v3-66d58645f4-t2xwq
Date: 05/Feb/2025:01:52:23 +0000
URI: /coffee
Request ID: f37a03870179ced04332162c0ee30c02

Does not match the regular expression, response from coffee-v1

curl --resolve cafe.example.com:$GW_PORT:$GW_IP http://cafe.example.com:$GW_PORT/coffee -H "headerRegex:header"
Handling connection for 8080
Server address: 10.244.0.109:8080
Server name: coffee-v1-767764946-jsql5
Date: 05/Feb/2025:01:52:36 +0000
URI: /coffee
Request ID: 96e3902a554461d3d48f082f77bca3a1

---

For GRPCRoute, header matching with regular expression we are configuring a headerRegex header and request is received by grpc-backend-2

apiVersion: gateway.networking.k8s.io/v1
kind: GRPCRoute
metadata:
  name: grpc-header-matching
spec:
  parentRefs:
  - name: same-namespace
  rules:
  # Matches "version: one"
  - matches:
    - headers:
      - name: version
        value: one
    backendRefs:
    - name: grpc-infra-backend-v1
      port: 8080
  # Matches "version: two"
  - matches:
    - headers:
      - name: version
        value: two
    backendRefs:
    - name: grpc-infra-backend-v2
      port: 8080
  # Matches "headerRegex: grpc-header-[a-z]{1}"
  - matches:
    - headers:
      - name: headerRegex
        value: "grpc-header-[a-z]{1}"
        type: RegularExpression
    backendRefs:
    - name: grpc-infra-backend-v2
      port: 8080

Matches the regular expression

grpcurl -plaintext -proto grpc.proto -authority bar.com -d '{"name": "version two regex"}' -H 'headerRegex: grpc-header-a' ${GW_IP}:${GW_PORT} helloworld.Greeter/SayHello
Handling connection for 8080
{
  "message": "Hello version two regex"
}

Does not match the regular expression

grpcurl -plaintext -proto grpc.proto -authority bar.com -d '{"name": "version two regex"}' -H 'headerRegex: two' ${GW_IP}:${GW_PORT} helloworld.Greeter/SayHello
Handling connection for 8080
ERROR:
  Code: Unimplemented
  Message: unexpected HTTP status code received from server: 404 (Not Found); transport: received unexpected content-type "text/html"

---

Functional Tests

• Adds tests to verify HTTPRoute and GRPCRoute with advanced route settings are configured with True/Accepted/True condition.
• Add test to verify working traffic to the HTTPRoute using headers and query params with type Exact and RegularExpression match type.

Please focus on (optional): If you any specific areas where you would like reviewers to focus their attention or provide
specific feedback, add them here.

Closes #1965
Closes #3101

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

Adds regex matching for headers and query params for HTTPRoutes and headers for GRPCRoutes.

[github-actions]

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---

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.08%. Comparing base (c9bd90c) to head (4e9fbde).
Report is 10 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3093      +/-   ##
==========================================
+ Coverage   90.06%   90.08%   +0.02%     
==========================================
  Files         112      112              
  Lines       11570    11596      +26     
  Branches       50       62      +12     
==========================================
+ Hits        10420    10446      +26     
  Misses       1089     1089              
  Partials       61       61              

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[sjberman]

Since there are no conformance tests for this, it feels like we should probably have a basic functional test for it.

Also, the docs changes should be in the docs repo, not here.

[salonichf5]

Since there are no conformance tests for this, it feels like we should probably have a basic functional test for it.
Let me work on that.

Also, the docs changes should be in the docs repo, not here.

Yeah put them here to be reviewed. Once I have approvals for this PR, i'll open it in the docs repo.

[ADubhlaoich]

Doc changes LGTM, but don't forget to make them in the documentation repository!

https://github.com/nginx/documentation

It should target the ngf release branch, ngf-release-2.0.

[bjee19]

lgtm!