c-go cache: Only cache discovery requests

Only cache discovery requests, and only for kubectl.

pkg/kubectl/cmd/util/factory.go

@@ -63,6 +63,10 @@ const (
 	FlagMatchBinaryVersion = "match-server-version"
 )
 
+var (
+	FlagHTTPCacheDir = "cache-dir"
+)
+
 // Factory provides abstractions that allow the Kubectl command to be extended across multiple types
 // of resources and different API sets.
 // The rings are here for a reason.  In order for composers to be able to provide alternative factory implementations
@@ -82,13 +86,17 @@ type Factory interface {
 type DiscoveryClientFactory interface {
 	// Returns a discovery client
 	DiscoveryClient() (discovery.CachedDiscoveryInterface, error)
+
+	// BindFlags adds any discovery flags that are common to all kubectl sub commands.
+	BindFlags(flags *pflag.FlagSet)
 }
 
 // ClientAccessFactory holds the first level of factory methods.
 // Generally provides discovery, negotiation, and no-dep calls.
 // TODO The polymorphic calls probably deserve their own interface.
 type ClientAccessFactory interface {
-	DiscoveryClientFactory
+	// Returns a discovery client
+	DiscoveryClient() (discovery.CachedDiscoveryInterface, error)
 
 	// ClientSet gives you back an internal, generated clientset
 	ClientSet() (internalclientset.Interface, error)

pkg/kubectl/cmd/util/factory_client_access.go

@@ -90,6 +90,7 @@ func NewClientAccessFactoryFromDiscovery(flags *pflag.FlagSet, clientConfig clie
 
 type discoveryFactory struct {
 	clientConfig clientcmd.ClientConfig
+	cacheDir     string
 }
 
 func (f *discoveryFactory) DiscoveryClient() (discovery.CachedDiscoveryInterface, error) {
@@ -97,6 +98,9 @@ func (f *discoveryFactory) DiscoveryClient() (discovery.CachedDiscoveryInterface
 	if err != nil {
 		return nil, err
 	}
+
+	cfg.CacheDir = f.cacheDir
+
 	discoveryClient, err := discovery.NewDiscoveryClientForConfig(cfg)
 	if err != nil {
 		return nil, err
@@ -105,6 +109,11 @@ func (f *discoveryFactory) DiscoveryClient() (discovery.CachedDiscoveryInterface
 	return NewCachedDiscoveryClient(discoveryClient, cacheDir, time.Duration(10*time.Minute)), nil
 }
 
+func (f *discoveryFactory) BindFlags(flags *pflag.FlagSet) {
+	defaultCacheDir := filepath.Join(homedir.HomeDir(), ".kube", "http-cache")
+	flags.StringVar(&f.cacheDir, FlagHTTPCacheDir, defaultCacheDir, "Default HTTP cache directory")
+}
+
 // DefaultClientConfig creates a clientcmd.ClientConfig with the following hierarchy:
 //   1.  Use the kubeconfig builder.  The number of merges and overrides here gets a little crazy.  Stay with me.
 //       1.  Merge the kubeconfig itself.  This is done with the following hierarchy rules:
@@ -377,6 +386,8 @@ func (f *ring0Factory) BindFlags(flags *pflag.FlagSet) {
 	// to do that automatically for every subcommand.
 	flags.BoolVar(&f.clientCache.matchVersion, FlagMatchBinaryVersion, false, "Require server version to match client version")
 
+	f.discoveryFactory.BindFlags(flags)
+
 	// Normalize all flags that are coming from other packages or pre-configurations
 	// a.k.a. change all "_" to "-". e.g. glog package
 	flags.SetNormalizeFunc(utilflag.WordSepNormalizeFunc)

staging/src/k8s.io/client-go/tools/clientcmd/client_config.go

@@ -22,7 +22,6 @@ import (
 	"io/ioutil"
 	"net/url"
 	"os"
-	"path/filepath"
 	"strings"
 
 	"github.com/golang/glog"
@@ -32,19 +31,16 @@ import (
 	restclient "k8s.io/client-go/rest"
 	clientauth "k8s.io/client-go/tools/auth"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
-	"k8s.io/client-go/util/homedir"
 )
 
 var (
 	// ClusterDefaults has the same behavior as the old EnvVar and DefaultCluster fields
 	// DEPRECATED will be replaced
 	ClusterDefaults = clientcmdapi.Cluster{Server: getDefaultServer()}
-	cacheDirDefault = filepath.Join(homedir.HomeDir(), ".kube", "http-cache")
 	// DefaultClientConfig represents the legacy behavior of this package for defaulting
 	// DEPRECATED will be replace
 	DefaultClientConfig = DirectClientConfig{*clientcmdapi.NewConfig(), "", &ConfigOverrides{
 		ClusterDefaults: ClusterDefaults,
-		CacheDir:        cacheDirDefault,
 	}, nil, NewDefaultClientConfigLoadingRules(), promptedCredentials{}}
 )
 
@@ -135,7 +131,6 @@ func (config *DirectClientConfig) ClientConfig() (*restclient.Config, error) {
 
 	clientConfig := &restclient.Config{}
 	clientConfig.Host = configClusterInfo.Server
-	clientConfig.CacheDir = config.overrides.CacheDir
 
 	if len(config.overrides.Timeout) > 0 {
 		timeout, err := ParseTimeout(config.overrides.Timeout)

staging/src/k8s.io/client-go/tools/clientcmd/overrides.go

@@ -17,13 +17,11 @@ limitations under the License.
 package clientcmd
 
 import (
-	"path/filepath"
 	"strconv"
 
 	"github.com/spf13/pflag"
 
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
-	"k8s.io/client-go/util/homedir"
 )
 
 // ConfigOverrides holds values that should override whatever information is pulled from the actual Config object.  You can't
@@ -36,7 +34,6 @@ type ConfigOverrides struct {
 	Context         clientcmdapi.Context
 	CurrentContext  string
 	Timeout         string
-	CacheDir        string
 }
 
 // ConfigOverrideFlags holds the flag names to be used for binding command line flags.  Notice that this structure tightly
@@ -47,7 +44,6 @@ type ConfigOverrideFlags struct {
 	ContextOverrideFlags ContextOverrideFlags
 	CurrentContext       FlagInfo
 	Timeout              FlagInfo
-	CacheDir             FlagInfo
 }
 
 // AuthOverrideFlags holds the flag names to be used for binding command line flags for AuthInfo objects
@@ -150,12 +146,10 @@ const (
 	FlagUsername         = "username"
 	FlagPassword         = "password"
 	FlagTimeout          = "request-timeout"
-	FlagCacheDir         = "cachedir"
 )
 
 // RecommendedConfigOverrideFlags is a convenience method to return recommended flag names prefixed with a string of your choosing
 func RecommendedConfigOverrideFlags(prefix string) ConfigOverrideFlags {
-	defaultCacheDir := filepath.Join(homedir.HomeDir(), ".kube", "http-cache")
 	return ConfigOverrideFlags{
 		AuthOverrideFlags:    RecommendedAuthOverrideFlags(prefix),
 		ClusterOverrideFlags: RecommendedClusterOverrideFlags(prefix),
@@ -163,7 +157,6 @@ func RecommendedConfigOverrideFlags(prefix string) ConfigOverrideFlags {
 
 		CurrentContext: FlagInfo{prefix + FlagContext, "", "", "The name of the kubeconfig context to use"},
 		Timeout:        FlagInfo{prefix + FlagTimeout, "", "0", "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."},
-		CacheDir:       FlagInfo{prefix + FlagCacheDir, "", defaultCacheDir, "Path to http-cache directory"},
 	}
 }
 
@@ -205,7 +198,6 @@ func BindOverrideFlags(overrides *ConfigOverrides, flags *pflag.FlagSet, flagNam
 	BindContextFlags(&overrides.Context, flags, flagNames.ContextOverrideFlags)
 	flagNames.CurrentContext.BindStringFlag(flags, &overrides.CurrentContext)
 	flagNames.Timeout.BindStringFlag(flags, &overrides.Timeout)
-	flagNames.CacheDir.BindStringFlag(flags, &overrides.CacheDir)
 }
 
 // BindAuthInfoFlags is a convenience method to bind the specified flags to their associated variables