Add override for proxy_intercept_errors when using Custom HTTP Errors (#9497)

* added proxy-intercept-errors config option

* fixed error when comparing locations

* fixed missing location config from annotation
added e2e test

* reversed logic for proxy-intercept-errors to disable-proxy-intercept-errors

* reversed logic to disable-proxy-intercept-errors

* reversed logic

* default has to be false

* put comment in same line as return

* run gofmt

* fixing wrong Boilerplate header

* updated code to new IngressAnnotation interface

* fixes to satisfy PR comments

* synced with upstream; fixed typo

* gofumpt disableproxyintercepterrors.go

* gofumpt

test/e2e/annotations/disableproxyintercepterrors.go

@@ -0,0 +1,100 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package annotations
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	networking "k8s.io/api/networking/v1"
+
+	"github.com/onsi/ginkgo/v2"
+	"github.com/stretchr/testify/assert"
+	"k8s.io/ingress-nginx/test/e2e/framework"
+)
+
+var _ = framework.DescribeAnnotation("disable-proxy-intercept-errors", func() {
+	f := framework.NewDefaultFramework("disable-proxy-intercept-errors")
+
+	ginkgo.BeforeEach(func() {
+		f.NewHttpbunDeployment()
+		f.NewEchoDeployment()
+	})
+
+	ginkgo.It("configures Nginx correctly", func() {
+		host := "pie.foo.com"
+
+		annotations := map[string]string{
+			"nginx.ingress.kubernetes.io/custom-http-errors":             "404",
+			"nginx.ingress.kubernetes.io/disable-proxy-intercept-errors": "true",
+			"nginx.ingress.kubernetes.io/default-backend":                framework.EchoService,
+		}
+
+		ingHTTPBunService := framework.NewSingleIngress(host, "/", host, f.Namespace, framework.HTTPBunService, 80, annotations)
+		f.EnsureIngress(ingHTTPBunService)
+
+		var serverConfig string
+		f.WaitForNginxServer(host, func(sc string) bool {
+			serverConfig = sc
+			return strings.Contains(serverConfig, fmt.Sprintf("server_name %s", host))
+		})
+
+		ginkgo.By("turning off proxy_intercept_errors directive")
+		assert.NotContains(ginkgo.GinkgoT(), serverConfig, "proxy_intercept_errors on;")
+
+		// the plan for client side testing
+		// create ingress where we disable intercept for code 404 - that error should get to the client
+		// the same ingress should intercept any other error (>300 and not 404) where we will get intercepted error
+		ginkgo.By("client test to check response - with intercept disabled")
+		requestID := "proxy_intercept_errors"
+
+		f.HTTPTestClient().
+			GET("/status/404").
+			WithHeader("Host", host).
+			WithHeader("x-request-id", requestID).
+			Expect().
+			Status(http.StatusNotFound).
+			Body().Empty()
+
+		ginkgo.By("client test to check response - with intercept enabled")
+		err := framework.UpdateIngress(f.KubeClientSet, f.Namespace, host, func(ingress *networking.Ingress) error {
+			ingress.ObjectMeta.Annotations["nginx.ingress.kubernetes.io/disable-proxy-intercept-errors"] = "false"
+			return nil
+		})
+		assert.Nil(ginkgo.GinkgoT(), err)
+
+		f.WaitForNginxServer(host, func(sc string) bool {
+			if serverConfig != sc {
+				serverConfig = sc
+				return true
+			}
+			return false
+		})
+
+		f.HTTPTestClient().
+			GET("/status/404").
+			WithHeader("Host", host).
+			WithHeader("x-request-id", requestID).
+			Expect().
+			Status(http.StatusOK).
+			Body().Contains("x-code=404").
+			Contains(fmt.Sprintf("x-ingress-name=%s", host)).
+			Contains(fmt.Sprintf("x-service-name=%s", framework.HTTPBunService)).
+			Contains(fmt.Sprintf("x-request-id=%s", requestID))
+	})
+})