Merge pull request #112580 from shyamjvs/disable-compression

Add --disable-compression flag to kubectl

staging/src/k8s.io/cli-runtime/pkg/genericclioptions/config_flags.go

@@ -55,6 +55,7 @@ const (
 	flagPassword           = "password"
 	flagTimeout            = "request-timeout"
 	flagCacheDir           = "cache-dir"
+	flagDisableCompression = "disable-compression"
 )
 
 // RESTClientGetter is an interface that the ConfigFlags describe to provide an easier way to mock for commands
@@ -97,6 +98,7 @@ type ConfigFlags struct {
 	Username           *string
 	Password           *string
 	Timeout            *string
+	DisableCompression *bool
 	// If non-nil, wrap config function can transform the Config
 	// before it is returned in ToRESTConfig function.
 	WrapConfigFn func(*rest.Config) *rest.Config
@@ -199,6 +201,9 @@ func (f *ConfigFlags) toRawKubeConfigLoader() clientcmd.ClientConfig {
 	if f.Insecure != nil {
 		overrides.ClusterInfo.InsecureSkipTLSVerify = *f.Insecure
 	}
+	if f.DisableCompression != nil {
+		overrides.ClusterInfo.DisableCompression = *f.DisableCompression
+	}
 
 	// bind context flags
 	if f.Context != nil {
@@ -393,6 +398,9 @@ func (f *ConfigFlags) AddFlags(flags *pflag.FlagSet) {
 	if f.Timeout != nil {
 		flags.StringVar(f.Timeout, flagTimeout, *f.Timeout, "The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests.")
 	}
+	if f.DisableCompression != nil {
+		flags.BoolVar(f.DisableCompression, flagDisableCompression, *f.DisableCompression, "If true, opt-out of response compression for all requests to the server")
+	}
 }
 
 // WithDeprecatedPasswordFlag enables the username and password config flags
@@ -424,6 +432,7 @@ func (f *ConfigFlags) WithWrapConfigFn(wrapConfigFn func(*rest.Config) *rest.Con
 func NewConfigFlags(usePersistentConfig bool) *ConfigFlags {
 	impersonateGroup := []string{}
 	insecure := false
+	disableCompression := false
 
 	return &ConfigFlags{
 		Insecure:   &insecure,
@@ -444,6 +453,7 @@ func NewConfigFlags(usePersistentConfig bool) *ConfigFlags {
 		Impersonate:        utilpointer.String(""),
 		ImpersonateUID:     utilpointer.String(""),
 		ImpersonateGroup:   &impersonateGroup,
+		DisableCompression: &disableCompression,
 
 		usePersistentConfig: usePersistentConfig,
 		// The more groups you have, the more discovery requests you need to make.

test/cmd/get.sh

@@ -253,6 +253,48 @@ run_retrieve_multiple_tests() {
   set +o errexit
 }
 
+run_kubectl_response_compression_tests() {
+  set -o nounset
+  set -o errexit
+
+  create_and_use_new_namespace
+  kube::log::status "Testing kubectl get objects with/without response compression"
+
+  ### Test creation of large configmap objects
+  # Pre-condition: no configmaps exists
+  kube::test::get_object_assert configmaps "{{range.items}}{{${id_field:?}}}:{{end}}" ''
+  # Commands to create 3 configmaps each of size 50KB. Sum of their sizes should be >128KB (defaultGzipThresholdBytes)
+  # for apiserver to allow gzip compression of the response. This is required to test the disable-compression option
+  # from client-side
+  some_string=$(dd status=none if=/dev/urandom bs=1K count=50 2>/dev/null | base64)
+  kubectl create configmap "cm-one" --from-literal=somekey="${some_string}"
+  kubectl create configmap "cm-two" --from-literal=somekey="${some_string}"
+  kubectl create configmap "cm-three" --from-literal=somekey="${some_string}"
+  output_message=$(kubectl get configmaps 2>&1 "${kube_flags[@]:?}")
+  # Post-condition: All configmaps should be created
+  kube::test::if_has_string "${output_message}" "cm-one"
+  kube::test::if_has_string "${output_message}" "cm-two"
+  kube::test::if_has_string "${output_message}" "cm-three"
+
+  ### Test list call WITH compression
+  output_message=$(kubectl get configmaps --v=8 2>&1 "${kube_flags[@]:?}")
+  # Post-condition: Response headers should include "accept-encoding" header
+  kube::test::if_has_string "${output_message}" "Vary: Accept-Encoding"
+
+  ### Test list call WITHOUT compression
+  output_message=$(kubectl get configmaps --disable-compression=true --v=8 2>&1 "${kube_flags[@]:?}")
+  # Post-condition: Response headers should NOT include "accept-encoding" header
+  kube::test::if_has_not_string "${output_message}" "Vary: Accept-Encoding"
+
+  # cleanup
+  kubectl delete configmap "cm-one"
+  kubectl delete configmap "cm-two"
+  kubectl delete configmap "cm-three"
+
+  set +o nounset
+  set +o errexit
+}
+
 run_kubectl_sort_by_tests() {
   set -o nounset
   set -o errexit