Router QueryParameterMatcher fails to respect present_match

[balogio]

Title: Router QueryParameterMatcher fails to respect present_match

Description:
When configuring a route matcher to match based on the non-existence of a query_parameter, the route is incorrectly matched when present_match is set to false. This causes traffic to be routed to the incorrect upstream.

Expected Functionality: Based on the documentation, I'd expect that setting present_match: true would return true if the param key exists, and false if the param key does not exist. present_match: false should then return false if the key exists, and true if the param key does not exist.

Repro steps:
All steps are using the example config in the below config section. Overall, this is very easy to reproduce.
envoy -c Path/To/example.yaml --service-cluster test_cluster --service-node test_node --log-level debug
The config should return the following responses:
/?foo -> foo
/?bar -> bar
/?foo=1&bar=1 -> Catchall Response!
/?anyOtherKey -> Catchall Response!

But running curl against http://localhost:10000 shows a very different story:
curl 'http://localhost:10000?foo' -> Catchall Response! -- should return foo
curl 'http://localhost:10000?foo=1' -> Catchall Response! -- should return foo
curl 'http://localhost:10000?foo=1&bar=1' -> foo -- should return Catchall Response!
curl 'http://localhost:10000?bar' -> Catchall Response! -- should return bar
curl 'http://localhost:10000?bar=1' -> Catchall Response! -- should return bar
curl 'http://localhost:10000?bar=1&foo=1' -> foo -- should return Catchall Response!
curl 'http://localhost:10000?anyOtherKey' -> correctly returns Catchall Response!

To really drive this home, comment out lines 19-40 in the example config, so that you are only left with the following 2 matchers:

             - match:
                  prefix: /
                  query_parameters:
                    - name: foo
                      present_match: false
                    - name: bar
                      present_match: false
                direct_response:
                  status: 200
                  body:
                    inline_string: "foo bar, you should never see this"
              - match:
                  prefix: "/"
                direct_response:
                  status: 200
                  body:
                    inline_string: "Catchall Response!"

We should get Catchall Response! for everything even if we pass in foo and bar in our request, but that is not the case:

curl 'http://localhost:10000?foo' -> Catchall - correct
curl 'http://localhost:10000?bar' -> Catchall - correct
curl 'http://localhost:10000?foo&bar' -> foo bar, you should never see this
curl 'http://localhost:10000?bar=1&foo=1' -> foo bar, you should never see this

Config:

static_resources:
  listeners:
  - name: listener_0
    address:
      socket_address: { address: 0.0.0.0, port_value: 10000 }
    filter_chains:
    - filters:
      - name: envoy.filters.network.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
          codec_type: AUTO
          stat_prefix: ingress_http
          route_config:
            name: local_route
            virtual_hosts:
            - name: local_service
              domains: ["*"]
              routes:
              - match:
                  prefix: /
                  query_parameters:
                    - name: "foo"
                      present_match: true
                    - name: "bar"
                      present_match: false
                direct_response:
                  status: 200
                  body:
                    inline_string: "foo" 
              - match:
                  prefix: /
                  query_parameters:
                    - name: foo
                      present_match: false
                    - name: bar
                      present_match: true
                direct_response:
                  status: 200
                  body:
                    inline_string: "bar"
              - match:
                  prefix: /
                  query_parameters:
                    - name: foo
                      present_match: false
                    - name: bar
                      present_match: false
                direct_response:
                  status: 200
                  body:
                    inline_string: "foo bar, you should never see this"
              - match:
                  prefix: "/"
                direct_response:
                  status: 200
                  body:
                    inline_string: "Catchall Response!"
          http_filters:
          - name: envoy.filters.http.router
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router

Envoy Info:

• version 1.31.0, brew install: https://formulae.brew.sh/formula/envoy

Related Issues:
This looks to be the same as #14656, which was present_match: false not being respected for HeaderMatch: #14656

[agrawroh]

Yeah, it looks like the present_match is not implemented for query parameters. I'll assign this to myself and will work on a fix.

[agrawroh]

/assign @agrawroh