add git.iim.gay/grufwub/go-store for storage backend, replacing blob.Storage

Signed-off-by: kim (grufwub) <grufwub@gmail.com>

vendor/git.iim.gay/grufwub/go-store/kv/state.go

@@ -0,0 +1,125 @@
+package kv
+
+import (
+	"io"
+
+	"git.iim.gay/grufwub/go-errors"
+)
+
+var ErrStateClosed = errors.Define("store/kv: state closed")
+
+// StateRO provides a read-only window to the store. While this
+// state is active during the Read() function window, the entire
+// store will be read-locked. The state is thread-safe for concurrent
+// use UNTIL the moment that your supplied function to Read() returns,
+// then the state has zero guarantees
+type StateRO struct {
+	store *KVStore
+}
+
+func (st *StateRO) Get(key string) ([]byte, error) {
+	// Check not closed
+	if st.store == nil {
+		return nil, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.get(key)
+}
+
+func (st *StateRO) GetStream(key string) (io.ReadCloser, error) {
+	// Check not closed
+	if st.store == nil {
+		return nil, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.getStream(key)
+}
+
+func (st *StateRO) Has(key string) (bool, error) {
+	// Check not closed
+	if st.store == nil {
+		return false, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.has(key)
+}
+
+func (st *StateRO) close() {
+	st.store = nil
+}
+
+// StateRW provides a read-write window to the store. While this
+// state is active during the Update() function window, the entire
+// store will be locked. The state is thread-safe for concurrent
+// use UNTIL the moment that your supplied function to Update() returns,
+// then the state has zero guarantees
+type StateRW struct {
+	store *KVStore
+}
+
+func (st *StateRW) Get(key string) ([]byte, error) {
+	// Check not closed
+	if st.store == nil {
+		return nil, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.get(key)
+}
+
+func (st *StateRW) GetStream(key string) (io.ReadCloser, error) {
+	// Check not closed
+	if st.store == nil {
+		return nil, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.getStream(key)
+}
+
+func (st *StateRW) Put(key string, value []byte) error {
+	// Check not closed
+	if st.store == nil {
+		return ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.put(key, value)
+}
+
+func (st *StateRW) PutStream(key string, r io.Reader) error {
+	// Check not closed
+	if st.store == nil {
+		return ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.putStream(key, r)
+}
+
+func (st *StateRW) Has(key string) (bool, error) {
+	// Check not closed
+	if st.store == nil {
+		return false, ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.has(key)
+}
+
+func (st *StateRW) Delete(key string) error {
+	// Check not closed
+	if st.store == nil {
+		return ErrStateClosed
+	}
+
+	// Pass request to store
+	return st.store.delete(key)
+}
+
+func (st *StateRW) close() {
+	st.store = nil
+}