{"record":{"id":"93239c418b765d82","repo":"kubernetes/kops","slug":"error-marshaling-object-v","errorCode":null,"errorMessage":"error marshaling object: %v","messagePattern":"error marshaling object: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"pkg/client/simple/vfsclientset/commonvfs.go","lineNumber":137,"sourceCode":"\tdata, err := configPath.ReadFile(ctx)\n\tif err != nil {\n\t\tif os.IsNotExist(err) {\n\t\t\treturn nil, err\n\t\t}\n\t\treturn nil, fmt.Errorf(\"error reading %s: %v\", configPath, err)\n\t}\n\n\tobject, _, err := kopscodecs.Decode(data, nil)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"error parsing %s: %v\", configPath, err)\n\t}\n\treturn object, nil\n}\n\nfunc (c *VFSClientBase) writeConfig(ctx context.Context, cluster *kops.Cluster, configPath vfs.Path, o runtime.Object, writeOptions ...vfs.WriteOption) error {\n\tdata, err := c.serialize(o)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"error marshaling object: %v\", err)\n\t}\n\n\tcreate := false\n\tfor _, writeOption := range writeOptions {\n\t\tswitch writeOption {\n\t\tcase vfs.WriteOptionCreate:\n\t\t\tcreate = true\n\t\tcase vfs.WriteOptionOnlyIfExists:\n\t\t\t_, err = configPath.ReadFile(ctx)\n\t\t\tif err != nil {\n\t\t\t\tif os.IsNotExist(err) {\n\t\t\t\t\treturn fmt.Errorf(\"cannot update configuration file %s: does not exist\", configPath)\n\t\t\t\t}\n\t\t\t\treturn fmt.Errorf(\"error checking if configuration file %s exists already: %v\", configPath, err)\n\t\t\t}\n\t\tdefault:\n\t\t\treturn fmt.Errorf(\"unknown write option: %q\", writeOption)\n\t\t}","sourceCodeStart":119,"sourceCodeEnd":155,"githubUrl":"https://github.com/kubernetes/kops/blob/4c8573c808a73d578c5eadc86d410646ea0b0d73/pkg/client/simple/vfsclientset/commonvfs.go#L119-L155","documentation":"writeConfig() failed while serializing the object before any write occurred: c.serialize(o) returned an error (itself wrapping encoder.Encode failures) and is re-wrapped as 'error marshaling object'. Called by Create, Update, create, and update.","triggerScenarios":"Create/Update on a vfs clientset where the object cannot be encoded by the configured encoder — unregistered type, invalid fields, or nil embedded structs.","commonSituations":"Programmatically built kops objects missing required fields; passing the wrong object kind to a typed client; kops version mismatch producing objects the current codecs cannot encode.","solutions":["Inspect the wrapped cause (%v) to find which field/type failed marshaling.","Validate/fully populate the object (required fields, correct Kind/APIVersion) before Create/Update.","Ensure you use the matching kops API types for the clientset version.","If caused by a kops upgrade bug, pin/upgrade kops to a compatible release."],"exampleFix":"// before\ncluster := &kops.Cluster{}  // missing ObjectMeta/Spec\nclientset.Create(ctx, cluster)\n// after\ncluster := &kops.Cluster{}\ncluster.ObjectMeta.Name = \"prod.example.com\"\ncluster.Spec = kops.ClusterSpec{ /* populated */ }\nclientset.Create(ctx, cluster)","handlingStrategy":"validation","validationCode":"if obj == nil || reflect.ValueOf(obj).IsNil() {\n    return errors.New(\"object must be non-nil\")\n}\nif obj.GetObjectKind().GroupVersionKind().Empty() {\n    return errors.New(\"object GroupVersionKind must be set before marshal\")\n}","typeGuard":"func isMarshalable(o interface{}) bool {\n    ro, ok := o.(runtime.Object)\n    return ok && ro != nil && !reflect.ValueOf(ro).IsNil() && !ro.GetObjectKind().GroupVersionKind().Empty()\n}","tryCatchPattern":"if err := client.Create(ctx, obj); err != nil && strings.Contains(err.Error(), \"error marshaling object\") {\n    return fmt.Errorf(\"check object fields/kind: %w\", err)\n}","preventionTips":["Fully populate objects (name, spec, GVK) before Create/Update.","Use typed kops clientsets with their matching API types.","Add round-trip (marshal/unmarshal) unit tests for constructed objects."],"tags":["vfs","serialization","marshaling","codec"],"backgroundTag":"object-encode-failed","analyzedSha":"4c8573c808a73d578c5eadc86d410646ea0b0d73","analyzedAt":"2026-09-05T04:13:19.212Z","contentChangedAt":"2026-09-05T04:13:19.212Z","schemaVersion":2},"datasetVersion":"2026-09-12T07:17:12.445Z"}