// SetList sets the given list object's Items member have the elements given in
// objects.
// Returns an error if list is not a List type (does not have an Items member),
// or if any of the objects are not of the right type.
func SetList(list runtime.Object, objects []runtime.Object) error {
itemsPtr, err := GetItemsPtr(list)
if err != nil {
return err
}
items, err := conversion.EnforcePtr(itemsPtr)
if err != nil {
return err
}
if items.Type() == objectSliceType {
items.Set(reflect.ValueOf(objects))
return nil
}
slice := reflect.MakeSlice(items.Type(), len(objects), len(objects))
for i := range objects {
dest := slice.Index(i)
src, err := conversion.EnforcePtr(objects[i])
if err != nil {
return err
}
if src.Type().AssignableTo(dest.Type()) {
dest.Set(src)
} else if src.Type().ConvertibleTo(dest.Type()) {
dest.Set(src.Convert(dest.Type()))
} else {
return fmt.Errorf("item[%d]: can't assign or convert %v into %v", i, src.Type(), dest.Type())
}
}
items.Set(slice)
return nil
}
// ExtractList returns obj's Items element as an array of runtime.Objects.
// Returns an error if obj is not a List type (does not have an Items member).
func ExtractList(obj runtime.Object) ([]runtime.Object, error) {
itemsPtr, err := GetItemsPtr(obj)
if err != nil {
return nil, err
}
items, err := conversion.EnforcePtr(itemsPtr)
if err != nil {
return nil, err
}
list := make([]runtime.Object, items.Len())
for i := range list {
raw := items.Index(i)
switch item := raw.Interface().(type) {
case runtime.RawExtension:
switch {
case item.Object != nil:
list[i] = item.Object
case item.Raw != nil:
// TODO: Set ContentEncoding and ContentType correctly.
list[i] = &runtime.Unknown{Raw: item.Raw}
default:
list[i] = nil
}
case runtime.Object:
list[i] = item
default:
var found bool
if list[i], found = raw.Addr().Interface().(runtime.Object); !found {
return nil, fmt.Errorf("%v: item[%v]: Expected object, got %#v(%s)", obj, i, raw.Interface(), raw.Kind())
}
}
}
return list, nil
}
// SetZeroValue would set the object of objPtr to zero value of its type.
func SetZeroValue(objPtr Object) error {
v, err := conversion.EnforcePtr(objPtr)
if err != nil {
return err
}
v.Set(reflect.Zero(v.Type()))
return nil
}
// ListMetaFor returns a pointer to a provided object's ListMeta,
// or an error if the object does not have that pointer.
// TODO: allow runtime.Unknown to extract this object
func ListMetaFor(obj runtime.Object) (*unversioned.ListMeta, error) {
v, err := conversion.EnforcePtr(obj)
if err != nil {
return nil, err
}
var meta *unversioned.ListMeta
err = runtime.FieldPtr(v, "ListMeta", &meta)
return meta, err
}
// GuaranteedUpdate implements storage.Interface.GuaranteedUpdate.
func (s *store) GuaranteedUpdate(ctx context.Context, key string, out runtime.Object, ignoreNotFound bool, precondtions *storage.Preconditions, tryUpdate storage.UpdateFunc) error {
v, err := conversion.EnforcePtr(out)
if err != nil {
panic("unable to convert output object to pointer")
}
key = keyWithPrefix(s.pathPrefix, key)
getResp, err := s.client.KV.Get(ctx, key)
if err != nil {
return err
}
for {
origState, err := s.getState(getResp, key, v, ignoreNotFound)
if err != nil {
return err
}
if err := checkPreconditions(key, precondtions, origState.obj); err != nil {
return err
}
ret, ttl, err := s.updateState(origState, tryUpdate)
if err != nil {
return err
}
data, err := runtime.Encode(s.codec, ret)
if err != nil {
return err
}
if bytes.Equal(data, origState.data) {
return decode(s.codec, s.versioner, origState.data, out, origState.rev)
}
opts, err := s.ttlOpts(ctx, int64(ttl))
if err != nil {
return err
}
txnResp, err := s.client.KV.Txn(ctx).If(
clientv3.Compare(clientv3.ModRevision(key), "=", origState.rev),
).Then(
clientv3.OpPut(key, string(data), opts...),
).Else(
clientv3.OpGet(key),
).Commit()
if err != nil {
return err
}
if !txnResp.Succeeded {
getResp = (*clientv3.GetResponse)(txnResp.Responses[0].GetResponseRange())
glog.V(4).Infof("GuaranteedUpdate of %s failed because of a conflict, going to retry", key)
continue
}
putResp := txnResp.Responses[0].GetResponsePut()
return decode(s.codec, s.versioner, data, out, putResp.Header.Revision)
}
}
// Implements storage.Interface.
func (c *Cacher) List(ctx context.Context, key string, resourceVersion string, filter FilterFunc, listObj runtime.Object) error {
if resourceVersion == "" {
// If resourceVersion is not specified, serve it from underlying
// storage (for backward compatibility).
return c.storage.List(ctx, key, resourceVersion, filter, listObj)
}
// If resourceVersion is specified, serve it from cache.
// It's guaranteed that the returned value is at least that
// fresh as the given resourceVersion.
listRV, err := ParseListResourceVersion(resourceVersion)
if err != nil {
return err
}
// To avoid situation when List is processed before the underlying
// watchCache is propagated for the first time, we acquire and immediately
// release the 'usable' lock.
// We don't need to hold it all the time, because watchCache is thread-safe
// and it would complicate already very difficult locking pattern.
c.usable.RLock()
c.usable.RUnlock()
// List elements from cache, with at least 'listRV'.
listPtr, err := meta.GetItemsPtr(listObj)
if err != nil {
return err
}
listVal, err := conversion.EnforcePtr(listPtr)
if err != nil || listVal.Kind() != reflect.Slice {
return fmt.Errorf("need a pointer to slice, got %v", listVal.Kind())
}
filterFunc := filterFunction(key, c.keyFunc, filter)
objs, readResourceVersion, err := c.watchCache.WaitUntilFreshAndList(listRV)
if err != nil {
return fmt.Errorf("failed to wait for fresh list: %v", err)
}
for _, obj := range objs {
object, ok := obj.(runtime.Object)
if !ok {
return fmt.Errorf("non runtime.Object returned from storage: %v", obj)
}
if filterFunc(object) {
listVal.Set(reflect.Append(listVal, reflect.ValueOf(object).Elem()))
}
}
if c.versioner != nil {
if err := c.versioner.UpdateList(listObj, readResourceVersion); err != nil {
return err
}
}
return nil
}
// Delete implements storage.Interface.Delete.
func (s *store) Delete(ctx context.Context, key string, out runtime.Object, precondtions *storage.Preconditions) error {
v, err := conversion.EnforcePtr(out)
if err != nil {
panic("unable to convert output object to pointer")
}
key = keyWithPrefix(s.pathPrefix, key)
if precondtions == nil {
return s.unconditionalDelete(ctx, key, out)
}
return s.conditionalDelete(ctx, key, out, v, precondtions)
}
// decode decodes value of bytes into object. It will also set the object resource version to rev.
// On success, objPtr would be set to the object.
func decode(codec runtime.Codec, versioner storage.Versioner, value []byte, objPtr runtime.Object, rev int64) error {
if _, err := conversion.EnforcePtr(objPtr); err != nil {
panic("unable to convert output object to pointer")
}
_, _, err := codec.Decode(value, nil, objPtr)
if err != nil {
return err
}
// being unable to set the version does not prevent the object from being extracted
versioner.UpdateObject(objPtr, uint64(rev))
return nil
}
func (s *Scheme) IsUnversioned(obj Object) (bool, bool) {
v, err := conversion.EnforcePtr(obj)
if err != nil {
return false, false
}
t := v.Type()
if _, ok := s.typeToGVK[t]; !ok {
return false, false
}
_, ok := s.unversionedTypes[t]
return ok, true
}
// ObjectKinds returns all possible group,version,kind of the go object, true if the
// object is considered unversioned, or an error if it's not a pointer or is unregistered.
func (s *Scheme) ObjectKinds(obj Object) ([]unversioned.GroupVersionKind, bool, error) {
v, err := conversion.EnforcePtr(obj)
if err != nil {
return nil, false, err
}
t := v.Type()
gvks, ok := s.typeToGVK[t]
if !ok {
return nil, false, ¬RegisteredErr{t: t}
}
_, unversionedType := s.unversionedTypes[t]
return gvks, unversionedType, nil
}
func listToItems(listObj runtime.Object) ([]runtime.Object, error) {
v, err := conversion.EnforcePtr(listObj)
if err != nil {
return nil, fmt.Errorf("unexpected error: %v", err)
}
items := v.FieldByName("Items")
if !items.IsValid() {
return nil, fmt.Errorf("unexpected Items field in %v", listObj)
}
if items.Type().Kind() != reflect.Slice {
return nil, fmt.Errorf("unexpected Items field type: %v", items.Type().Kind())
}
result := make([]runtime.Object, items.Len())
for i := 0; i < items.Len(); i++ {
result[i] = items.Index(i).Addr().Interface().(runtime.Object)
}
return result, nil
}
// decodeList decodes a list of values into a list of objects, with resource version set to corresponding rev.
// On success, ListPtr would be set to the list of objects.
func decodeList(elems []*elemForDecode, filter storage.FilterFunc, ListPtr interface{}, codec runtime.Codec, versioner storage.Versioner) error {
v, err := conversion.EnforcePtr(ListPtr)
if err != nil || v.Kind() != reflect.Slice {
panic("need ptr to slice")
}
for _, elem := range elems {
obj, _, err := codec.Decode(elem.data, nil, reflect.New(v.Type().Elem()).Interface().(runtime.Object))
if err != nil {
return err
}
// being unable to set the version does not prevent the object from being extracted
versioner.UpdateObject(obj, elem.rev)
if filter(obj) {
v.Set(reflect.Append(v, reflect.ValueOf(obj).Elem()))
}
}
return nil
}
// Field puts the value of fieldName, which must be a member of v, into dest,
// which must be a variable to which this field's value can be assigned.
func Field(v reflect.Value, fieldName string, dest interface{}) error {
field := v.FieldByName(fieldName)
if !field.IsValid() {
return fmt.Errorf("couldn't find %v field in %#v", fieldName, v.Interface())
}
destValue, err := conversion.EnforcePtr(dest)
if err != nil {
return err
}
if field.Type().AssignableTo(destValue.Type()) {
destValue.Set(field)
return nil
}
if field.Type().ConvertibleTo(destValue.Type()) {
destValue.Set(field.Convert(destValue.Type()))
return nil
}
return fmt.Errorf("couldn't assign/convert %v to %v", field.Type(), destValue.Type())
}
// GetItemsPtr returns a pointer to the list object's Items member.
// If 'list' doesn't have an Items member, it's not really a list type
// and an error will be returned.
// This function will either return a pointer to a slice, or an error, but not both.
func GetItemsPtr(list runtime.Object) (interface{}, error) {
v, err := conversion.EnforcePtr(list)
if err != nil {
return nil, err
}
items := v.FieldByName("Items")
if !items.IsValid() {
return nil, fmt.Errorf("no Items field in %#v", list)
}
switch items.Kind() {
case reflect.Interface, reflect.Ptr:
target := reflect.TypeOf(items.Interface()).Elem()
if target.Kind() != reflect.Slice {
return nil, fmt.Errorf("items: Expected slice, got %s", target.Kind())
}
return items.Interface(), nil
case reflect.Slice:
return items.Addr().Interface(), nil
default:
return nil, fmt.Errorf("items: Expected slice, got %s", items.Kind())
}
}