feat: added DECRBY command

echovault/api_generic.go

@@ -461,3 +461,28 @@ func (server *EchoVault) Decr(key string) (int, error) {
 	// Parse the integer response
 	return internal.ParseIntegerResponse(b)
 }
+
+// DecrBy decrements the integer value of the specified key by the given increment.
+// If the key does not exist, it is created with an initial value of 0 before decrementing.
+// If the value stored at the key is not an integer, an error is returned.
+//
+// Parameters:
+// - `key` (string): The key whose value is to be decremented.
+// - `increment` (int): The amount by which to decrement the key's value. This can be a positive or negative integer.
+//
+// Returns:
+// - (int): The new value of the key after the decrement operation.
+
+func (server *EchoVault) DecrBy(key string, value string) (int, error) {
+	// Construct the command
+	cmd := []string{"DECRBY", key, value}
+
+	// Execute the command
+	b, err := server.handleCommand(server.context, internal.EncodeCommand(cmd), nil, false, true)
+	if err != nil {
+		return 0, err
+	}
+
+	// Parse the integer response
+	return internal.ParseIntegerResponse(b)
+}