Add transaction to delete assets recursively

assets/delete.go

@@ -2,6 +2,7 @@ package assets
 
 import (
 	"encoding/json"
+	"strings"
 
 	"github.com/goledgerdev/cc-tools/errors"
 	"github.com/hyperledger/fabric/core/chaincode/shim"
@@ -59,3 +60,88 @@ func (a *Asset) Delete(stub shim.ChaincodeStubInterface) ([]byte, error) {
 
 	return assetJSON, nil
 }
+
+// DeleteRecursive erases asset and recursively erases those which reference it
+func (a *Asset) DeleteRecursive(stub shim.ChaincodeStubInterface) ([]byte, error) {
+	var err error
+
+	// Check if org has write permission
+	err = a.CheckWriters(stub)
+	if err != nil {
+		return nil, errors.WrapError(err, "failed write permission check")
+	}
+
+	err = deleteRecursive(stub, a.Key())
+	if err != nil {
+		return nil, errors.WrapError(err, "error deleting asset Recursively")
+	}
+
+	response := map[string]interface{}{
+		"deletedKeys": deletedKeys,
+	}
+	responseJSON, err := json.Marshal(response)
+	if err != nil {
+		return nil, errors.WrapError(err, "failed to marshal response")
+	}
+
+	return responseJSON, nil
+}
+
+var deletedKeys []string
+
+func deleteRecursive(stub shim.ChaincodeStubInterface, key string) error {
+	deletedKeys = append(deletedKeys, key)
+	queryIt, err := stub.GetStateByPartialCompositeKey(key, []string{})
+	if err != nil {
+		return errors.WrapErrorWithStatus(err, "failed to check reference index", 500)
+	}
+	defer queryIt.Close()
+
+	for queryIt.HasNext() {
+		next, _ := queryIt.Next()
+		referrerKeyString := strings.ReplaceAll(next.Key, key, "")
+		referrerKeyString = strings.ReplaceAll(referrerKeyString, "\x00", "")
+		var isDeleted bool
+
+		for _, deletedKey := range deletedKeys {
+			if deletedKey == referrerKeyString {
+				isDeleted = true
+				break
+			}
+		}
+		if !isDeleted {
+			err = deleteRecursive(stub, referrerKeyString)
+			if err != nil {
+				return errors.WrapError(err, "error deleting referrer asset:")
+			}
+		}
+	}
+
+	keyMap := make(map[string]interface{})
+	keyMap["@key"] = key
+	assetKey, err := NewKey(keyMap)
+
+	asset, err := assetKey.Get(stub)
+	if err != nil {
+		return errors.WrapError(err, "failed to read asset from blockchain")
+	}
+	// Clean up reference markers for this asset
+	err = asset.delRefs(stub)
+	if err != nil {
+		return errors.WrapError(err, "failed cleaning reference index")
+	}
+
+	if !asset.IsPrivate() {
+		err = stub.DelState(asset.Key())
+		if err != nil {
+			return errors.WrapError(err, "failed to delete state from ledger")
+		}
+	} else {
+		err = stub.DelPrivateData(asset.TypeTag(), asset.Key())
+		if err != nil {
+			return errors.WrapError(err, "failed to delete state from private collection")
+		}
+	}
+
+	return nil
+}

assets/references.go

@@ -121,6 +121,9 @@ func (a Asset) delRefs(stub shim.ChaincodeStubInterface) errors.ICCError {
 	for _, referencedKey := range refKeys {
 		// Construct reference key
 		indexKey, err := stub.CreateCompositeKey(referencedKey.Key(), []string{assetKey})
+		if err != nil {
+			return errors.WrapErrorWithStatus(err, "could not create composite key", 400)
+		}
 		// Check if asset exists in blockchain
 		err = stub.DelState(indexKey)
 		if err != nil {

transactions/deleteAsset.go

@@ -42,3 +42,40 @@ var DeleteAsset = Transaction{
 		return response, nil
 	},
 }
+
+// DeleteRecursive deletes an asset and it's recursive referrers from the blockchain
+var DeleteRecursive = Transaction{
+	Tag:         "deleteAssetRecursive",
+	Label:       "Delete Asset",
+	Method:      "DELETE",
+	Description: "",
+
+	MetaTx: true,
+	Args: []Argument{
+		{
+			Tag:         "key",
+			Description: "Key of the asset to be deleted.",
+			DataType:    "@key",
+			Required:    true,
+		},
+	},
+	Routine: func(stub shim.ChaincodeStubInterface, req map[string]interface{}) ([]byte, errors.ICCError) {
+		// This is safe to do because validation is done before calling routine
+		key := req["key"].(assets.Key)
+
+		var err error
+
+		// Fetch asset from blockchain
+		asset, err := key.Get(stub)
+		if err != nil {
+			return nil, errors.WrapError(err, "failed to read asset from blockchain")
+		}
+
+		response, err := asset.DeleteRecursive(stub)
+		if err != nil {
+			return nil, errors.WrapError(err, "failed to delete asset recursively")
+		}
+
+		return response, nil
+	},
+}

transactions/txList.go

@@ -12,6 +12,7 @@ var basicTxs = []Transaction{
 	Search,
 	UpdateAsset,
 	DeleteAsset,
+	DeleteRecursive,
 }
 
 // TxList returns a copy of the txList variable