// List implements storage.Interface.List.
func (s *store) List(ctx context.Context, key, resourceVersion string, filter storage.FilterFunc, listObj runtime.Object) error {
listPtr, err := meta.GetItemsPtr(listObj)
if err != nil {
return err
}
key = keyWithPrefix(s.pathPrefix, key)
// We need to make sure the key ended with "/" so that we only get children "directories".
// e.g. if we have key "/a", "/a/b", "/ab", getting keys with prefix "/a" will return all three,
// while with prefix "/a/" will return only "/a/b" which is the correct answer.
if !strings.HasSuffix(key, "/") {
key += "/"
}
getResp, err := s.client.KV.Get(ctx, key, clientv3.WithPrefix())
if err != nil {
return err
}
elems := make([]*elemForDecode, len(getResp.Kvs))
for i, kv := range getResp.Kvs {
elems[i] = &elemForDecode{
data: kv.Value,
rev: uint64(kv.ModRevision),
}
}
if err := decodeList(elems, filter, listPtr, s.codec, s.versioner); err != nil {
return err
}
// update version with cluster level revision
return s.versioner.UpdateList(listObj, uint64(getResp.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
}
// GetToList implements storage.Interface.GetToList.
func (s *store) GetToList(ctx context.Context, key string, filter storage.FilterFunc, listObj runtime.Object) error {
listPtr, err := meta.GetItemsPtr(listObj)
if err != nil {
return err
}
key = keyWithPrefix(s.pathPrefix, key)
getResp, err := s.client.KV.Get(ctx, key)
if err != nil {
return err
}
if len(getResp.Kvs) == 0 {
return nil
}
elems := []*elemForDecode{{
data: getResp.Kvs[0].Value,
rev: uint64(getResp.Kvs[0].ModRevision),
}}
if err := decodeList(elems, filter, listPtr, s.codec, s.versioner); err != nil {
return err
}
// update version with cluster level revision
return s.versioner.UpdateList(listObj, uint64(getResp.Header.Revision))
}
