Manually set GVK in extract, add commentary to extractor

real_cluster_script.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"os"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -23,12 +24,17 @@ import (
 	"sigs.k8s.io/structured-merge-diff/v4/typed"
 )
 
+// This is a small hacky script that tests the extract config against a real cluster
+// to demonstrate a bug I'm seeing with the GVKParser where it claims there
+// are duplicate GVK entries
+// TODO: don't commit this, delete it before merging.
+// Any and all functionality from this script should be captured in the appropriate integration test.
 func main() {
-	fmt.Println("vim-go")
 	defaultNS := "default"
 	mydep := "mydep"
 	mgr := "mymanager"
-	kubeconfig := "/usr/local/google/home/kevindelgado/.kube/config"
+	// TODO: make this an arg
+	kubeconfig := os.Getenv("KUBECONFIG")
 
 	config, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
 	if err != nil {

staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/helpers.go

@@ -337,12 +337,8 @@ func (s unstructuredJSONScheme) Decode(data []byte, _ *schema.GroupVersionKind,
 	}
 
 	gvk := obj.GetObjectKind().GroupVersionKind()
-	//goruntime.Breakpoint()
 	if len(gvk.Kind) == 0 {
-		//goruntime.Breakpoint()
-		//return nil, &gvk, runtime.NewMissingKindErr(string(data))
-		fmt.Println("MISSING KIND, ignoring err")
-		fmt.Printf("string(data) = %+v\n", string(data))
+		return nil, &gvk, runtime.NewMissingKindErr(string(data))
 	}
 
 	return obj, &gvk, nil

staging/src/k8s.io/apimachinery/pkg/util/managedfields/extract.go

@@ -75,16 +75,13 @@ func ExtractInto(object runtime.Object, objectType typed.ParseableType, fieldMan
 	if !ok {
 		return fmt.Errorf("unable to convert managed fields for %s to unstructured, expected map, got %T", fieldManager, u)
 	}
-	fmt.Printf("u = %+v\n", u)
-	fmt.Println("---")
-	fmt.Printf("typedObj = %+v\n", typedObj)
-	fmt.Println("---")
-	fmt.Printf("object = %+v\n", object)
-	fmt.Println("---")
-	fmt.Printf("m = %+v\n", m)
-	fmt.Println("---")
-	fmt.Printf("applyConfiguration = %+v\n", applyConfiguration)
-	fmt.Println("---")
+
+	// set the type meta manually if it doesn't exist to avoid missing kind errors
+	// when decoding from unstructured JSON
+	if _, ok := m["kind"]; !ok {
+		m["kind"] = object.GetObjectKind().GroupVersionKind().Kind
+		m["apiVersion"] = object.GetObjectKind().GroupVersionKind().GroupVersion().String()
+	}
 	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(m, applyConfiguration); err != nil {
 		return fmt.Errorf("error extracting into obj from unstructured: %w", err)
 	}

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/fieldmanager/gvkparser.go

@@ -65,15 +65,12 @@ func NewGVKParser(models proto.Models, preserveUnknownFields bool) (*GvkParser,
 			panic(fmt.Sprintf("ListModels returns a model that can't be looked-up for: %v", modelName))
 		}
 		gvkList := parseGroupVersionKind(model)
-		//fmt.Println("+++")
-		//fmt.Printf("gvkList = %+v\n", gvkList)
-		//fmt.Println("+++")
 		for _, gvk := range gvkList {
 			if len(gvk.Kind) > 0 {
 				_, ok := parser.gvks[gvk]
 				if ok {
-					//return nil, fmt.Errorf("duplicate entry for %v", gvk)
-					fmt.Printf("duplicate entry for %v\n", gvk)
+					// TODO: double check why this is failing in real_cluster_script.go
+					return nil, fmt.Errorf("duplicate entry for %v", gvk)
 				}
 				parser.gvks[gvk] = modelName
 			}

staging/src/k8s.io/client-go/applyconfigurations/meta/v1/unstructured.go

@@ -10,20 +10,27 @@ import (
 	"sigs.k8s.io/structured-merge-diff/v4/typed"
 )
 
+// UnstructuredExtractor enables extracting the applied configuration state from object for fieldManager into an
+// unstructured object type.
 type UnstructuredExtractor interface {
 	ExtractUnstructured(object *unstructured.Unstructured, fieldManager string) (*unstructured.Unstructured, error)
 	ExtractUnstructuredStatus(object *unstructured.Unstructured, fieldManager string) (*unstructured.Unstructured, error)
 }
 
-type parserCache interface {
-	parserForGVK(gvk schema.GroupVersionKind) (*typed.ParseableType, error)
+// objectTypeCache is a cache of typed.ParseableTypes
+type objectTypeCache interface {
+	objectTypeForGVK(gvk schema.GroupVersionKind) (*typed.ParseableType, error)
 }
 
-type nonCachingParserCache struct {
+// nonCachingObjectTypeCache is a objectTypeCache that does no caching
+// (i.e. it downloads the OpenAPISchema every time)
+// Useful during the proof-of-concept stage until we agree on a caching solution.
+type nonCachingObjectTypeCache struct {
 	discoveryClient *discovery.DiscoveryClient
 }
 
-func (c *nonCachingParserCache) parserForGVK(gvk schema.GroupVersionKind) (*typed.ParseableType, error) {
+// objectTypeForGVK retrieves the typed.ParseableType for a given gvk from the cache
+func (c *nonCachingObjectTypeCache) objectTypeForGVK(gvk schema.GroupVersionKind) (*typed.ParseableType, error) {
 	doc, err := c.discoveryClient.OpenAPISchema()
 	if err != nil {
 		return nil, err
@@ -43,31 +50,38 @@ func (c *nonCachingParserCache) parserForGVK(gvk schema.GroupVersionKind) (*type
 }
 
 type extractor struct {
-	cache parserCache
+	cache objectTypeCache
 }
 
+// NewUnstructuredExtractor creates the extractor with which you can extract the applied configuration
+// for a given manager from an unstructured object.
 func NewUnstructuredExtractor(dc *discovery.DiscoveryClient) UnstructuredExtractor {
 	return &extractor{
-		cache: &nonCachingParserCache{dc},
+		cache: &nonCachingObjectTypeCache{dc},
 	}
 }
 
+// ExtractUnstructured extracts the applied configuration owned by fiieldManager from an unstructured object.
+// Note that the apply configuration itself is also an unstructured object.
 func (e *extractor) ExtractUnstructured(object *unstructured.Unstructured, fieldManager string) (*unstructured.Unstructured, error) {
 	return e.extractUnstructured(object, fieldManager, "")
 }
 
+// ExtractUnstructuredStatus is the same as ExtractUnstructured except
+// that it extracts the status subresource applied configuration.
+// Experimental!
 func (e *extractor) ExtractUnstructuredStatus(object *unstructured.Unstructured, fieldManager string) (*unstructured.Unstructured, error) {
 	return e.extractUnstructured(object, fieldManager, "status")
 }
 
 func (e *extractor) extractUnstructured(object *unstructured.Unstructured, fieldManager string, subresource string) (*unstructured.Unstructured, error) {
 	gvk := object.GetObjectKind().GroupVersionKind()
-	parser, err := e.cache.parserForGVK(gvk)
+	objectType, err := e.cache.objectTypeForGVK(gvk)
 	if err != nil {
 		return nil, err
 	}
 	result := &unstructured.Unstructured{}
-	err = managedfields.ExtractInto(object, *parser, fieldManager, result, subresource)
+	err = managedfields.ExtractInto(object, *objectType, fieldManager, result, subresource)
 	if err != nil {
 		return nil, err
 	}

vendor/sigs.k8s.io/structured-merge-diff/v4/value/reflectcache.go

@@ -269,7 +269,6 @@ func (e TypeReflectCacheEntry) FromUnstructured(sv, dv reflect.Value) error {
 	if err != nil {
 		return fmt.Errorf("error encoding %s to json: %v", st.String(), err)
 	}
-	// TODO: this is where we're failing
 	if unmarshaler, ok := e.getJsonUnmarshaler(dv); ok {
 		return unmarshaler.UnmarshalJSON(data)
 	}