feat(configmap): expose gzip-disable (#9505)

* docs(configmap): add link for gzip-min-length

* feat(configmap): expose gzip-disable

* test(e2e): cover gzip settings

* docs(configmap): simplify description with NGINX link

* refactor(configmap): simplify condition

test/e2e/settings/gzip.go

@@ -0,0 +1,99 @@
+/*
+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 settings
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/onsi/ginkgo/v2"
+
+	"k8s.io/ingress-nginx/internal/ingress/controller/config"
+	"k8s.io/ingress-nginx/test/e2e/framework"
+)
+
+var _ = framework.DescribeSetting("gzip", func() {
+	f := framework.NewDefaultFramework("gzip")
+
+	ginkgo.It("should be disabled by default", func() {
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return !strings.Contains(cfg, "gzip on;")
+			})
+	})
+
+	ginkgo.It("should be enabled with default settings", func() {
+		f.UpdateNginxConfigMapData("use-gzip", "true")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				defaultCfg := config.NewDefault()
+				return strings.Contains(cfg, "gzip on;") &&
+					strings.Contains(cfg, fmt.Sprintf("gzip_comp_level %d;", defaultCfg.GzipLevel)) &&
+					!strings.Contains(cfg, "gzip_disable") &&
+					strings.Contains(cfg, "gzip_http_version 1.1;") &&
+					strings.Contains(cfg, fmt.Sprintf("gzip_min_length %d;", defaultCfg.GzipMinLength)) &&
+					strings.Contains(cfg, fmt.Sprintf("gzip_types %s;", defaultCfg.GzipTypes)) &&
+					strings.Contains(cfg, "gzip_proxied any;") &&
+					strings.Contains(cfg, "gzip_vary on;")
+			})
+	})
+
+	ginkgo.It("should set gzip_comp_level to 4", func() {
+		f.UpdateNginxConfigMapData("use-gzip", "true")
+		f.UpdateNginxConfigMapData("gzip-level", "4")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "gzip on;") &&
+					strings.Contains(cfg, "gzip_comp_level 4;")
+			})
+	})
+
+	ginkgo.It("should set gzip_disable to msie6", func() {
+		f.UpdateNginxConfigMapData("use-gzip", "true")
+		f.UpdateNginxConfigMapData("gzip-disable", "msie6")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "gzip on;") &&
+					strings.Contains(cfg, `gzip_disable "msie6";`)
+			})
+	})
+
+	ginkgo.It("should set gzip_min_length to 100", func() {
+		f.UpdateNginxConfigMapData("use-gzip", "true")
+		f.UpdateNginxConfigMapData("gzip-min-length", "100")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "gzip on;") &&
+					strings.Contains(cfg, "gzip_min_length 100;")
+			})
+	})
+
+	ginkgo.It("should set gzip_types to application/javascript", func() {
+		f.UpdateNginxConfigMapData("use-gzip", "true")
+		f.UpdateNginxConfigMapData("gzip-types", "application/javascript")
+
+		f.WaitForNginxConfiguration(
+			func(cfg string) bool {
+				return strings.Contains(cfg, "gzip on;") &&
+					strings.Contains(cfg, "gzip_types application/javascript;")
+			})
+	})
+})