openapi: Remove cache mechanism

The cache will be removed and replaced with HTTP Etag caching instead.
This patch is simply removing the existing mechanism.

pkg/kubectl/cmd/util/factory_object_mapping.go

@@ -439,13 +439,7 @@ func (f *ring1Factory) SwaggerSchema(gvk schema.GroupVersionKind) (*swagger.ApiD
 }
 
 // OpenAPISchema returns metadata and structural information about Kubernetes object definitions.
-// Will try to cache the data to a local file.  Cache is written and read from a
-// file created with ioutil.TempFile and obeys the expiration semantics of that file.
-// The cache location is a function of the client and server versions so that the open API
-// schema will be cached separately for different client / server combinations.
-// Note, the cache will not be invalidated if the server changes its open API schema without
-// changing the server version.
-func (f *ring1Factory) OpenAPISchema(cacheDir string) (openapi.Resources, error) {
+func (f *ring1Factory) OpenAPISchema() (openapi.Resources, error) {
 	discovery, err := f.clientAccessFactory.DiscoveryClient()
 	if err != nil {
 		return nil, err
@@ -453,23 +447,8 @@ func (f *ring1Factory) OpenAPISchema(cacheDir string) (openapi.Resources, error)
 
 	// Lazily initialize the OpenAPIGetter once
 	f.openAPIGetter.once.Do(func() {
-		// Get the server version for caching the openapi spec
-		versionString := ""
-		version, err := discovery.ServerVersion()
-		if err != nil {
-			// Cache the result under the server version
-			versionString = version.String()
-		}
-
-		// Get the cache directory for caching the openapi spec
-		cacheDir, err = substituteUserHome(cacheDir)
-		if err != nil {
-			// Don't cache the result if we couldn't substitute the home directory
-			cacheDir = ""
-		}
-
 		// Create the caching OpenAPIGetter
-		f.openAPIGetter.getter = openapi.NewOpenAPIGetter(cacheDir, versionString, discovery)
+		f.openAPIGetter.getter = openapi.NewOpenAPIGetter(discovery)
 	})
 
 	// Delegate to the OpenAPIGetter