add delete state in chaincode runtime

Author: noel2004

chaincode/lib/runtime/shim_state_map.go

@@ -45,6 +45,11 @@ func (w *shimStateMap) SetRaw(key string, raw []byte) error {
 	}
 	return w.stub.PutState(w.path+key, raw)
 }
+
+func (w *shimStateMap) Delete(key string) error {
+	return w.stub.DelState(w.path + key)
+}
+
 func (w *shimStateMap) Get(key string, m StorageObject) error {
 
 	raw, err := w.GetRaw(key)

chaincode/lib/runtime/state.go

@@ -43,6 +43,7 @@ type StateMap interface {
 	SetRaw(string, []byte) error
 	Get(string, StorageObject) error
 	Set(string, StorageObject) error
+	Delete(string) error
 }
 
 //default

chaincode/lib/runtime/state_legacy.go

@@ -79,6 +79,10 @@ func (w *shimStateMapROLegacy) Set(string, p.Message) error {
 	return nil
 }
 
+func (w *shimStateMapLegacy) Delete(key string) error {
+	return w.stub.DelState(w.path + key)
+}
+
 //default
 func NewShimMapLegacy(root string, stub shim.ChaincodeStubInterface, readOnly bool) StateMap_Legacy {
 	if readOnly {