Added helpers.php

src/helpers.php

@@ -0,0 +1,15 @@
+<?php
+
+// is_json helper
+if (! function_exists('is_json')) {
+	function is_json($string) {
+		try {
+			json_decode($string);
+
+		} catch (\Exception $e) {
+			return FALSE;
+		}
+
+		return (json_last_error() == JSON_ERROR_NONE);
+	}
+}