Add possibility to disable suggester by a cookie (#2237)

Author: ahornace

opengrok-indexer/src/main/java/org/opengrok/indexer/web/Scripts.java

@@ -126,7 +126,7 @@ public String toHtml() {
         SCRIPTS.put("jquery-tablesorter", new FileScript("js/jquery-tablesorter-2.26.6.min.js", 12));
         SCRIPTS.put("tablesorter-parsers", new FileScript("js/tablesorter-parsers-0.0.1.js", 13));
         SCRIPTS.put("searchable-option-list", new FileScript("js/searchable-option-list-2.0.5.min.js", 14));
-        SCRIPTS.put("utils", new FileScript("js/utils-0.0.23.js", 15));
+        SCRIPTS.put("utils", new FileScript("js/utils-0.0.24.js", 15));
         SCRIPTS.put("repos", new FileScript("js/repos-0.0.1.js", 20));
         SCRIPTS.put("diff", new FileScript("js/diff-0.0.3.js", 20));
         SCRIPTS.put("jquery-caret", new FileScript("js/jquery.caret-1.5.2.min.js", 25));

opengrok-web/src/main/webapp/js/utils-0.0.23.js renamed to opengrok-web/src/main/webapp/js/utils-0.0.24.js

@@ -1716,6 +1716,11 @@ function pageReadyMast() {
 }
 
 function domReadyMenu(minisearch) {
+    if (getCookie('OpenGrokSuggester.enabled') === 'false') {
+        console.log('Suggester disabled by a cookie');
+        return;
+    }
+
     $.ajax({
         // cannot use "/api/v1/configuration/suggester" because of security
         url: window.contextPath + "/api/v1/suggest/config",
@@ -2326,3 +2331,24 @@ function escapeHtml(string) { // taken from https://stackoverflow.com/questions/
         return htmlEscapeMap[s];
     });
 }
+
+/**
+ * Taken from https://www.w3schools.com/js/js_cookies.asp .
+ * @param cname cookie name to retrieve
+ * @returns {string} cookie value
+ */
+function getCookie(cname) {
+    var name = cname + "=";
+    var decodedCookie = decodeURIComponent(document.cookie);
+    var ca = decodedCookie.split(';');
+    for (var i = 0; i < ca.length; i++) {
+        var c = ca[i];
+        while (c.charAt(0) == ' ') {
+            c = c.substring(1);
+        }
+        if (c.indexOf(name) == 0) {
+            return c.substring(name.length, c.length);
+        }
+    }
+    return "";
+}