Documentation ¶
Overview ¶
Package client contains functionality for interacting with Kubernetes API servers.
Clients ¶
Clients are split into two interfaces -- Readers and Writers. Readers get and list, while writers create, update, and delete.
The New function can be used to create a new client that talks directly to the API server.
A common pattern in Kubernetes to read from a cache and write to the API server. This pattern is covered by the DelegatingClient type, which can be used to have a client whose Reader is different from the Writer.
Options ¶
Many client operations in Kubernetes support options. These options are represented as variadic arguments at the end of a given method call. For instance, to use a label selector on list, you can call
err := someReader.List(context.Background(), &podList, client.MatchingLabels(someLabelMap))
Indexing ¶
Indexes may be added to caches using a FieldIndexer. This allows you to easily and efficiently look up objects with certain properties. You can then make use of the index by specifying a field selector on calls to List on the Reader corresponding to the given Cache.
For instance, a Secret controller might have an index on the `.spec.volumes.secret.secretName` field in Pod objects, so that it could easily look up all pods that reference a given secret.
Index ¶
- type Client
- type CreateOptionFunc
- type CreateOptions
- type DelegatingClient
- type DelegatingReader
- type DeleteOptionFunc
- type DeleteOptions
- type FieldIndexer
- type IndexerFunc
- type ListOptionFunc
- type ListOptions
- func (o *ListOptions) ApplyOptions(optFuncs []ListOptionFunc) *ListOptions
- func (o *ListOptions) AsListOptions() *metav1.ListOptions
- func (o *ListOptions) InNamespace(ns string) *ListOptions
- func (o *ListOptions) MatchingField(name, val string) *ListOptions
- func (o *ListOptions) MatchingLabels(lbls map[string]string) *ListOptions
- func (o *ListOptions) SetFieldSelector(selRaw string) error
- func (o *ListOptions) SetLabelSelector(selRaw string) error
- type ObjectKey
- type Options
- type Patch
- type PatchOptionFunc
- type PatchOptions
- type Reader
- type StatusClient
- type StatusWriter
- type UpdateOptionFunc
- type UpdateOptions
- type Writer
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Client ¶
type Client interface { Reader Writer StatusClient }
Client knows how to perform CRUD operations on Kubernetes objects.
Example (Create) ¶
This example shows how to use the client with typed and unstrucurted objects to create objects.
package main import ( "context" corev1 "k8s.io/api/core/v1" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured" "k8s.io/apimachinery/pkg/runtime/schema" "sigs.k8s.io/controller-runtime/pkg/client" ) var c client.Client func main() { // Using a typed object. pod := &corev1.Pod{ ObjectMeta: metav1.ObjectMeta{ Namespace: "namespace", Name: "name", }, Spec: corev1.PodSpec{ Containers: []corev1.Container{ corev1.Container{ Image: "nginx", Name: "nginx", }, }, }, } // c is a created client. _ = c.Create(context.Background(), pod) // Using a unstructured object. u := &unstructured.Unstructured{} u.Object = map[string]interface{}{ "name": "name", "namespace": "namespace", "spec": map[string]interface{}{ "replicas": 2, "selector": map[string]interface{}{ "matchLabels": map[string]interface{}{ "foo": "bar", }, }, "template": map[string]interface{}{ "labels": map[string]interface{}{ "foo": "bar", }, "spec": map[string]interface{}{ "containers": []map[string]interface{}{ { "name": "nginx", "image": "nginx", }, }, }, }, }, } u.SetGroupVersionKind(schema.GroupVersionKind{ Group: "apps", Kind: "Deployment", Version: "v1", }) _ = c.Create(context.Background(), u) }
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Example (Delete) ¶
This example shows how to use the client with typed and unstrucurted objects to delete objects.
package main import ( "context" corev1 "k8s.io/api/core/v1" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured" "k8s.io/apimachinery/pkg/runtime/schema" "sigs.k8s.io/controller-runtime/pkg/client" ) var c client.Client func main() { // Using a typed object. pod := &corev1.Pod{ ObjectMeta: metav1.ObjectMeta{ Namespace: "namespace", Name: "name", }, } // c is a created client. _ = c.Delete(context.Background(), pod) // Using a unstructured object. u := &unstructured.Unstructured{} u.Object = map[string]interface{}{ "name": "name", "namespace": "namespace", } u.SetGroupVersionKind(schema.GroupVersionKind{ Group: "apps", Kind: "Deployment", Version: "v1", }) _ = c.Delete(context.Background(), u) }
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Example (Get) ¶
This example shows how to use the client with typed and unstructured objects to retrieve a objects.
package main import ( "context" corev1 "k8s.io/api/core/v1" "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured" "k8s.io/apimachinery/pkg/runtime/schema" "sigs.k8s.io/controller-runtime/pkg/client" ) var c client.Client func main() { // Using a typed object. pod := &corev1.Pod{} // c is a created client. _ = c.Get(context.Background(), client.ObjectKey{ Namespace: "namespace", Name: "name", }, pod) // Using a unstructured object. u := &unstructured.Unstructured{} u.SetGroupVersionKind(schema.GroupVersionKind{ Group: "apps", Kind: "Deployment", Version: "v1", }) _ = c.Get(context.Background(), client.ObjectKey{ Namespace: "namespace", Name: "name", }, u) }
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Example (List) ¶
This example shows how to use the client with typed and unstrucurted objects to list objects.
package main import ( "context" corev1 "k8s.io/api/core/v1" "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured" "k8s.io/apimachinery/pkg/runtime/schema" "sigs.k8s.io/controller-runtime/pkg/client" ) var c client.Client func main() { // Using a typed object. pod := &corev1.PodList{} // c is a created client. _ = c.List(context.Background(), pod) // Using a unstructured object. u := &unstructured.UnstructuredList{} u.SetGroupVersionKind(schema.GroupVersionKind{ Group: "apps", Kind: "DeploymentList", Version: "v1", }) _ = c.List(context.Background(), u) }
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Example (Update) ¶
This example shows how to use the client with typed and unstrucurted objects to update objects.
package main import ( "context" corev1 "k8s.io/api/core/v1" "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured" "k8s.io/apimachinery/pkg/runtime/schema" "sigs.k8s.io/controller-runtime/pkg/client" ) var c client.Client func main() { // Using a typed object. pod := &corev1.Pod{} // c is a created client. _ = c.Get(context.Background(), client.ObjectKey{ Namespace: "namespace", Name: "name", }, pod) pod.SetFinalizers(append(pod.GetFinalizers(), "new-finalizer")) _ = c.Update(context.Background(), pod) // Using a unstructured object. u := &unstructured.Unstructured{} u.SetGroupVersionKind(schema.GroupVersionKind{ Group: "apps", Kind: "Deployment", Version: "v1", }) _ = c.Get(context.Background(), client.ObjectKey{ Namespace: "namespace", Name: "name", }, u) u.SetFinalizers(append(u.GetFinalizers(), "new-finalizer")) _ = c.Update(context.Background(), u) }
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func New ¶
New returns a new Client using the provided config and Options. The returned client reads *and* writes directly from the server (it doesn't use object caches). It understands how to work with normal types (both custom resources and aggregated/built-in resources), as well as unstructured types.
In the case of normal types, the scheme will be used to look up the corresponding group, version, and kind for the given type. In the case of unstrctured types, the group, version, and kind will be extracted from the corresponding fields on the object.
Example ¶
package main import ( "context" "fmt" "os" corev1 "k8s.io/api/core/v1" "sigs.k8s.io/controller-runtime/pkg/client" "sigs.k8s.io/controller-runtime/pkg/client/config" ) func main() { cl, err := client.New(config.GetConfigOrDie(), client.Options{}) if err != nil { fmt.Println("failed to create client") os.Exit(1) } podList := &corev1.PodList{} err = cl.List(context.Background(), podList, client.InNamespace("default")) if err != nil { fmt.Printf("failed to list pods in namespace default: %v\n", err) os.Exit(1) } }
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type CreateOptionFunc ¶
type CreateOptionFunc func(*CreateOptions)
CreateOptionFunc is a function that mutates a CreateOptions struct. It implements the functional options pattern. See https://github.com/tmrts/go-patterns/blob/master/idiom/functional-options.md.
func CreateDryRunAll ¶ added in v0.2.0
func CreateDryRunAll() CreateOptionFunc
CreateDryRunAll is a functional option that sets the DryRun field of a CreateOptions struct to metav1.DryRunAll.
type CreateOptions ¶ added in v0.2.0
type CreateOptions struct { // When present, indicates that modifications should not be // persisted. An invalid or unrecognized dryRun directive will // result in an error response and no further processing of the // request. Valid values are: // - All: all dry run stages will be processed DryRun []string // Raw represents raw CreateOptions, as passed to the API server. Raw *metav1.CreateOptions }
CreateOptions contains options for create requests. It's generally a subset of metav1.CreateOptions.
func (*CreateOptions) ApplyOptions ¶ added in v0.2.0
func (o *CreateOptions) ApplyOptions(optFuncs []CreateOptionFunc) *CreateOptions
ApplyOptions executes the given CreateOptionFuncs and returns the mutated CreateOptions.
func (*CreateOptions) AsCreateOptions ¶ added in v0.2.0
func (o *CreateOptions) AsCreateOptions() *metav1.CreateOptions
AsCreateOptions returns these options as a metav1.CreateOptions. This may mutate the Raw field.
type DelegatingClient ¶
type DelegatingClient struct { Reader Writer StatusClient }
DelegatingClient forms a Client by composing separate reader, writer and statusclient interfaces. This way, you can have an Client that reads from a cache and writes to the API server.
type DelegatingReader ¶ added in v0.1.4
DelegatingReader forms a Reader that will cause Get and List requests for unstructured types to use the ClientReader while requests for any other type of object with use the CacheReader. This avoids accidentally caching the entire cluster in the common case of loading arbitrary unstructured objects (e.g. from OwnerReferences).
func (*DelegatingReader) Get ¶ added in v0.1.4
Get retrieves an obj for a given object key from the Kubernetes Cluster.
func (*DelegatingReader) List ¶ added in v0.1.4
func (d *DelegatingReader) List(ctx context.Context, list runtime.Object, opts ...ListOptionFunc) error
List retrieves list of objects for a given namespace and list options.
type DeleteOptionFunc ¶ added in v0.1.3
type DeleteOptionFunc func(*DeleteOptions)
DeleteOptionFunc is a function that mutates a DeleteOptions struct. It implements the functional options pattern. See https://github.com/tmrts/go-patterns/blob/master/idiom/functional-options.md.
func GracePeriodSeconds ¶ added in v0.1.3
func GracePeriodSeconds(gp int64) DeleteOptionFunc
GracePeriodSeconds is a functional option that sets the GracePeriodSeconds field of a DeleteOptions struct.
func Preconditions ¶ added in v0.1.3
func Preconditions(p *metav1.Preconditions) DeleteOptionFunc
Preconditions is a functional option that sets the Preconditions field of a DeleteOptions struct.
func PropagationPolicy ¶ added in v0.1.3
func PropagationPolicy(p metav1.DeletionPropagation) DeleteOptionFunc
PropagationPolicy is a functional option that sets the PropagationPolicy field of a DeleteOptions struct.
type DeleteOptions ¶ added in v0.1.3
type DeleteOptions struct { // GracePeriodSeconds is the duration in seconds before the object should be // deleted. Value must be non-negative integer. The value zero indicates // delete immediately. If this value is nil, the default grace period for the // specified type will be used. GracePeriodSeconds *int64 // Preconditions must be fulfilled before a deletion is carried out. If not // possible, a 409 Conflict status will be returned. Preconditions *metav1.Preconditions // PropagationPolicy determined whether and how garbage collection will be // performed. Either this field or OrphanDependents may be set, but not both. // The default policy is decided by the existing finalizer set in the // metadata.finalizers and the resource-specific default policy. // Acceptable values are: 'Orphan' - orphan the dependents; 'Background' - // allow the garbage collector to delete the dependents in the background; // 'Foreground' - a cascading policy that deletes all dependents in the // foreground. PropagationPolicy *metav1.DeletionPropagation // Raw represents raw DeleteOptions, as passed to the API server. Raw *metav1.DeleteOptions }
DeleteOptions contains options for delete requests. It's generally a subset of metav1.DeleteOptions.
func (*DeleteOptions) ApplyOptions ¶ added in v0.1.3
func (o *DeleteOptions) ApplyOptions(optFuncs []DeleteOptionFunc) *DeleteOptions
ApplyOptions executes the given DeleteOptionFuncs and returns the mutated DeleteOptions.
func (*DeleteOptions) AsDeleteOptions ¶ added in v0.1.3
func (o *DeleteOptions) AsDeleteOptions() *metav1.DeleteOptions
AsDeleteOptions returns these options as a metav1.DeleteOptions. This may mutate the Raw field.
type FieldIndexer ¶
type FieldIndexer interface { // IndexFields adds an index with the given field name on the given object type // by using the given function to extract the value for that field. If you want // compatibility with the Kubernetes API server, only return one key, and only use // fields that the API server supports. Otherwise, you can return multiple keys, // and "equality" in the field selector means that at least one key matches the value. // The FieldIndexer will automatically take care of indexing over namespace // and supporting efficient all-namespace queries. IndexField(obj runtime.Object, field string, extractValue IndexerFunc) error }
FieldIndexer knows how to index over a particular "field" such that it can later be used by a field selector.
Example (SecretName) ¶
This example shows how to set up and consume a field selector over a pod's volumes' secretName field.
package main import ( "context" corev1 "k8s.io/api/core/v1" "k8s.io/apimachinery/pkg/runtime" "sigs.k8s.io/controller-runtime/pkg/client" ) var ( c client.Client someIndexer client.FieldIndexer ) func main() { // someIndexer is a FieldIndexer over a Cache _ = someIndexer.IndexField(&corev1.Pod{}, "spec.volumes.secret.secretName", func(o runtime.Object) []string { var res []string for _, vol := range o.(*corev1.Pod).Spec.Volumes { if vol.Secret == nil { continue } // just return the raw field value -- the indexer will take care of dealing with namespaces for us res = append(res, vol.Secret.SecretName) } return res }) // elsewhere (e.g. in your reconciler) mySecretName := "someSecret" // derived from the reconcile.Request, for instance var podsWithSecrets corev1.PodList _ = c.List(context.Background(), &podsWithSecrets, client.MatchingField("spec.volumes.secret.secretName", mySecretName)) }
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type IndexerFunc ¶
IndexerFunc knows how to take an object and turn it into a series of non-namespaced keys. Namespaced objects are automatically given namespaced and non-spaced variants, so keys do not need to include namespace.
type ListOptionFunc ¶
type ListOptionFunc func(*ListOptions)
ListOptionFunc is a function that mutates a ListOptions struct. It implements the functional options pattern. See https://github.com/tmrts/go-patterns/blob/master/idiom/functional-options.md.
func InNamespace ¶
func InNamespace(ns string) ListOptionFunc
InNamespace is a functional option that sets the Namespace field of a ListOptions struct.
func MatchingField ¶
func MatchingField(name, val string) ListOptionFunc
MatchingField is a functional option that sets the FieldSelector field of a ListOptions struct.
func MatchingLabels ¶
func MatchingLabels(lbls map[string]string) ListOptionFunc
MatchingLabels is a functional option that sets the LabelSelector field of a ListOptions struct.
func UseListOptions ¶
func UseListOptions(newOpts *ListOptions) ListOptionFunc
UseListOptions is a functional option that replaces the fields of a ListOptions struct with those of a different ListOptions struct.
Example: cl.List(ctx, list, client.UseListOptions(lo.InNamespace(ns).MatchingLabels(labels)))
type ListOptions ¶
type ListOptions struct { // LabelSelector filters results by label. Use SetLabelSelector to // set from raw string form. LabelSelector labels.Selector // FieldSelector filters results by a particular field. In order // to use this with cache-based implementations, restrict usage to // a single field-value pair that's been added to the indexers. FieldSelector fields.Selector // Namespace represents the namespace to list for, or empty for // non-namespaced objects, or to list across all namespaces. Namespace string // Raw represents raw ListOptions, as passed to the API server. Note // that these may not be respected by all implementations of interface, // and the LabelSelector and FieldSelector fields are ignored. Raw *metav1.ListOptions }
ListOptions contains options for limiting or filtering results. It's generally a subset of metav1.ListOptions, with support for pre-parsed selectors (since generally, selectors will be executed against the cache).
func (*ListOptions) ApplyOptions ¶ added in v0.2.0
func (o *ListOptions) ApplyOptions(optFuncs []ListOptionFunc) *ListOptions
ApplyOptions executes the given ListOptionFuncs and returns the mutated ListOptions.
func (*ListOptions) AsListOptions ¶
func (o *ListOptions) AsListOptions() *metav1.ListOptions
AsListOptions returns these options as a flattened metav1.ListOptions. This may mutate the Raw field.
func (*ListOptions) InNamespace ¶
func (o *ListOptions) InNamespace(ns string) *ListOptions
InNamespace is a convenience function that sets the namespace, and then returns the options. It mutates the list options.
func (*ListOptions) MatchingField ¶
func (o *ListOptions) MatchingField(name, val string) *ListOptions
MatchingField is a convenience function that sets the field selector to match the given field, and then returns the options. It mutates the list options.
func (*ListOptions) MatchingLabels ¶
func (o *ListOptions) MatchingLabels(lbls map[string]string) *ListOptions
MatchingLabels is a convenience function that sets the label selector to match the given labels, and then returns the options. It mutates the list options.
func (*ListOptions) SetFieldSelector ¶
func (o *ListOptions) SetFieldSelector(selRaw string) error
SetFieldSelector sets this the label selector of these options from a string form of the selector.
func (*ListOptions) SetLabelSelector ¶
func (o *ListOptions) SetLabelSelector(selRaw string) error
SetLabelSelector sets this the label selector of these options from a string form of the selector.
type Options ¶
type Options struct { // Scheme, if provided, will be used to map go structs to GroupVersionKinds Scheme *runtime.Scheme // Mapper, if provided, will be used to map GroupVersionKinds to Resources Mapper meta.RESTMapper }
Options are creation options for a Client
type Patch ¶ added in v0.2.0
type Patch interface { // Type is the PatchType of the patch. Type() types.PatchType // Data is the raw data representing the patch. Data(obj runtime.Object) ([]byte, error) }
Patch is a patch that can be applied to a Kubernetes object.
func ConstantPatch ¶ added in v0.2.0
ConstantPatch constructs a new Patch with the given PatchType and data.
type PatchOptionFunc ¶
type PatchOptionFunc func(*PatchOptions)
PatchOptionFunc is a function that mutates a PatchOptions struct. It implements the functional options pattern. See https://github.com/tmrts/go-patterns/blob/master/idiom/functional-options.md.
func PatchDryRunAll ¶ added in v0.2.0
func PatchDryRunAll() PatchOptionFunc
PatchDryRunAll is a functional option that sets the DryRun field of a PatchOptions struct to metav1.DryRunAll.
func PatchWithForce ¶
func PatchWithForce() PatchOptionFunc
PatchWithForce is a functional option that sets the Force field of a PatchOptions struct to true.
type PatchOptions ¶ added in v0.2.0
type PatchOptions struct { // When present, indicates that modifications should not be // persisted. An invalid or unrecognized dryRun directive will // result in an error response and no further processing of the // request. Valid values are: // - All: all dry run stages will be processed DryRun []string // Force is going to "force" Apply requests. It means user will // re-acquire conflicting fields owned by other people. Force // flag must be unset for non-apply patch requests. // +optional Force *bool // Raw represents raw PatchOptions, as passed to the API server. Raw *metav1.PatchOptions }
PatchOptions contains options for patch requests.
func (*PatchOptions) ApplyOptions ¶ added in v0.2.0
func (o *PatchOptions) ApplyOptions(optFuncs []PatchOptionFunc) *PatchOptions
ApplyOptions executes the given PatchOptionFuncs, mutating these PatchOptions. It returns the mutated PatchOptions for convenience.
func (*PatchOptions) AsPatchOptions ¶ added in v0.2.0
func (o *PatchOptions) AsPatchOptions() *metav1.PatchOptions
AsPatchOptions returns these options as a metav1.PatchOptions. This may mutate the Raw field.
type Reader ¶
type Reader interface { // Get retrieves an obj for the given object key from the Kubernetes Cluster. // obj must be a struct pointer so that obj can be updated with the response // returned by the Server. Get(ctx context.Context, key ObjectKey, obj runtime.Object) error // List retrieves list of objects for a given namespace and list options. On a // successful call, Items field in the list will be populated with the // result returned from the server. List(ctx context.Context, list runtime.Object, opts ...ListOptionFunc) error }
Reader knows how to read and list Kubernetes objects.
type StatusClient ¶
type StatusClient interface {
Status() StatusWriter
}
StatusClient knows how to create a client which can update status subresource for kubernetes objects.
type StatusWriter ¶
type StatusWriter interface { // Update updates the fields corresponding to the status subresource for the // given obj. obj must be a struct pointer so that obj can be updated // with the content returned by the Server. Update(ctx context.Context, obj runtime.Object) error }
StatusWriter knows how to update status subresource of a Kubernetes object.
type UpdateOptionFunc ¶
type UpdateOptionFunc func(*UpdateOptions)
UpdateOptionFunc is a function that mutates a UpdateOptions struct. It implements the functional options pattern. See https://github.com/tmrts/go-patterns/blob/master/idiom/functional-options.md.
func UpdateDryRunAll ¶ added in v0.2.0
func UpdateDryRunAll() UpdateOptionFunc
UpdateDryRunAll is a functional option that sets the DryRun field of a UpdateOptions struct to metav1.DryRunAll.
type UpdateOptions ¶ added in v0.2.0
type UpdateOptions struct { // When present, indicates that modifications should not be // persisted. An invalid or unrecognized dryRun directive will // result in an error response and no further processing of the // request. Valid values are: // - All: all dry run stages will be processed DryRun []string // Raw represents raw UpdateOptions, as passed to the API server. Raw *metav1.UpdateOptions }
UpdateOptions contains options for create requests. It's generally a subset of metav1.UpdateOptions.
func (*UpdateOptions) ApplyOptions ¶ added in v0.2.0
func (o *UpdateOptions) ApplyOptions(optFuncs []UpdateOptionFunc) *UpdateOptions
ApplyOptions executes the given UpdateOptionFuncs and returns the mutated UpdateOptions.
func (*UpdateOptions) AsUpdateOptions ¶ added in v0.2.0
func (o *UpdateOptions) AsUpdateOptions() *metav1.UpdateOptions
AsUpdateOptions returns these options as a metav1.UpdateOptions. This may mutate the Raw field.
type Writer ¶
type Writer interface { // Create saves the object obj in the Kubernetes cluster. Create(ctx context.Context, obj runtime.Object, opts ...CreateOptionFunc) error // Delete deletes the given obj from Kubernetes cluster. Delete(ctx context.Context, obj runtime.Object, opts ...DeleteOptionFunc) error // Update updates the given obj in the Kubernetes cluster. obj must be a // struct pointer so that obj can be updated with the content returned by the Server. Update(ctx context.Context, obj runtime.Object, opts ...UpdateOptionFunc) error // Patch patches the given obj in the Kubernetes cluster. obj must be a // struct pointer so that obj can be updated with the content returned by the Server. Patch(ctx context.Context, obj runtime.Object, patch Patch, opts ...PatchOptionFunc) error }
Writer knows how to create, delete, and update Kubernetes objects.
Source Files ¶
Directories ¶
Path | Synopsis |
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Package apiutil contains utilities for working with raw Kubernetes API machinery, such as creating RESTMappers and raw REST clients, and extracting the GVK of an object.
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Package apiutil contains utilities for working with raw Kubernetes API machinery, such as creating RESTMappers and raw REST clients, and extracting the GVK of an object. |
Package config contains libraries for initializing REST configs for talking to the Kubernetes API
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Package config contains libraries for initializing REST configs for talking to the Kubernetes API |
Package fake provides a fake client for testing.
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Package fake provides a fake client for testing. |