Golang Key.AppID方法代码示例

// Split splits the key into its constituent parts. Note that if the key is
// not Valid, this method may not provide a round-trip for k.
func Split(k ds.Key) (appID, namespace string, toks []ds.KeyTok) {
	if k == nil {
		return
	}

	if sk, ok := k.(*Generic); ok {
		if sk == nil {
			return
		}
		return sk.appID, sk.namespace, sk.toks
	}

	n := 0
	for i := k; i != nil; i = i.Parent() {
		n++
	}
	toks = make([]ds.KeyTok, n)
	for i := k; i != nil; i = i.Parent() {
		n--
		toks[n].IntID = i.IntID()
		toks[n].StringID = i.StringID()
		toks[n].Kind = i.Kind()
	}
	appID = k.AppID()
	namespace = k.Namespace()
	return
}

func (d *dataStoreData) fixKeyLocked(ents *memCollection, key *ds.Key) (*ds.Key, error) {
	if key.Incomplete() {
		id, err := d.allocateIDsLocked(ents, key, 1)
		if err != nil {
			return key, err
		}
		key = ds.NewKey(key.AppID(), key.Namespace(), key.Kind(), "", id, key.Parent())
	}
	return key, nil
}

// Equal returns true iff the two keys represent identical key values.
func Equal(a, b ds.Key) (ret bool) {
	ret = (a.Kind() == b.Kind() &&
		a.StringID() == b.StringID() &&
		a.IntID() == b.IntID() &&
		a.AppID() == b.AppID() &&
		a.Namespace() == b.Namespace())
	if !ret {
		return
	}
	ap, bp := a.Parent(), b.Parent()
	return (ap == nil && bp == nil) || Equal(ap, bp)
}

func (d *dataStoreData) entsKeyLocked(key ds.Key) (*memCollection, ds.Key) {
	coll := "ents:" + key.Namespace()
	ents := d.head.GetCollection(coll)
	if ents == nil {
		ents = d.head.SetCollection(coll, nil)
	}

	if dskey.Incomplete(key) {
		idKey := []byte(nil)
		if key.Parent() == nil {
			idKey = rootIDsKey(key.Kind())
		} else {
			idKey = groupIDsKey(key)
		}
		id := incrementLocked(ents, idKey)
		key = dskey.New(key.AppID(), key.Namespace(), key.Kind(), "", id, key.Parent())
	}

	return ents, key
}

// Encode encodes the provided key as a base64-encoded protobuf.
//
// This encoding is compatible with the SDK-provided encoding and is agnostic
// to the underlying implementation of the Key.
//
// It's encoded with the urlsafe base64 table.
func Encode(k ds.Key) string {
	n := 0
	for i := k; i != nil; i = i.Parent() {
		n++
	}
	e := make([]*pb.Path_Element, n)
	for i := k; i != nil; i = i.Parent() {
		n--
		kind := i.Kind()
		e[n] = &pb.Path_Element{
			Type: &kind,
		}
		// At most one of {Name,Id} should be set.
		// Neither will be set for incomplete keys.
		if i.StringID() != "" {
			sid := i.StringID()
			e[n].Name = &sid
		} else if i.IntID() != 0 {
			iid := i.IntID()
			e[n].Id = &iid
		}
	}
	var namespace *string
	if k.Namespace() != "" {
		namespace = proto.String(k.Namespace())
	}
	r, err := proto.Marshal(&pb.Reference{
		App:       proto.String(k.AppID()),
		NameSpace: namespace,
		Path: &pb.Path{
			Element: e,
		},
	})
	if err != nil {
		panic(err)
	}

	// trim padding
	return strings.TrimRight(base64.URLEncoding.EncodeToString(r), "=")
}

// Valid determines if a key is valid, according to a couple rules:
//   - k is not nil
//   - every token of k:
//     - (if !allowSpecial) token's kind doesn't start with '__'
//     - token's kind and appid are non-blank
//     - token is not incomplete
//   - all tokens have the same namespace and appid
func Valid(k ds.Key, allowSpecial bool, aid, ns string) bool {
	if k == nil {
		return false
	}
	if aid != k.AppID() || ns != k.Namespace() {
		return false
	}
	for ; k != nil; k = k.Parent() {
		if !allowSpecial && len(k.Kind()) >= 2 && k.Kind()[:2] == "__" {
			return false
		}
		if k.Kind() == "" || k.AppID() == "" {
			return false
		}
		if k.StringID() != "" && k.IntID() != 0 {
			return false
		}
		if k.Parent() != nil {
			if k.Parent().Incomplete() {
				return false
			}
			if k.Parent().AppID() != k.AppID() || k.Parent().Namespace() != k.Namespace() {
				return false
			}
		}
	}
	return true
}

// PartialValid returns true iff this key is suitable for use in a Put
// operation. This is the same as Valid(k, false, ...), but also allowing k to
// be Incomplete().
func PartialValid(k ds.Key, aid, ns string) bool {
	if k.Incomplete() {
		k = New(k.AppID(), k.Namespace(), k.Kind(), "", 1, k.Parent())
	}
	return Valid(k, false, aid, ns)
}