Fix Javascript issue on non sqlite databases

When a non sqlite database is used, loading the admin interface fails
because the backup button is not generated.
This PR is solves it by checking if the elements are valid.

Also made some other changes and fixed some eslint errors.
Showing `_post` errors is better now.

Update jquery to latest version.

Fixes #3166

src/static/scripts/admin_users.js

@@ -1,6 +1,8 @@
 "use strict";
+/* eslint-env es2017, browser, jquery */
+/* global _post:readable, BASE_URL:readable, reload:readable, jdenticon:readable */
 
-function deleteUser() {
+function deleteUser(event) {
     event.preventDefault();
     event.stopPropagation();
     const id = event.target.parentNode.dataset.vwUserUuid;
@@ -22,7 +24,7 @@ function deleteUser() {
     }
 }
 
-function remove2fa() {
+function remove2fa(event) {
     event.preventDefault();
     event.stopPropagation();
     const id = event.target.parentNode.dataset.vwUserUuid;
@@ -36,7 +38,7 @@ function remove2fa() {
     );
 }
 
-function deauthUser() {
+function deauthUser(event) {
     event.preventDefault();
     event.stopPropagation();
     const id = event.target.parentNode.dataset.vwUserUuid;
@@ -50,7 +52,7 @@ function deauthUser() {
     );
 }
 
-function disableUser() {
+function disableUser(event) {
     event.preventDefault();
     event.stopPropagation();
     const id = event.target.parentNode.dataset.vwUserUuid;
@@ -68,7 +70,7 @@ function disableUser() {
     }
 }
 
-function enableUser() {
+function enableUser(event) {
     event.preventDefault();
     event.stopPropagation();
     const id = event.target.parentNode.dataset.vwUserUuid;
@@ -86,7 +88,7 @@ function enableUser() {
     }
 }
 
-function updateRevisions() {
+function updateRevisions(event) {
     event.preventDefault();
     event.stopPropagation();
     _post(`${BASE_URL}/admin/users/update_revision`,
@@ -95,7 +97,7 @@ function updateRevisions() {
     );
 }
 
-function inviteUser() {
+function inviteUser(event) {
     event.preventDefault();
     event.stopPropagation();
     const email = document.getElementById("inviteEmail");
@@ -182,7 +184,7 @@ userOrgTypeDialog.addEventListener("hide.bs.modal", function() {
     document.getElementById("userOrgTypeOrgUuid").value = "";
 }, false);
 
-function updateUserOrgType() {
+function updateUserOrgType(event) {
     event.preventDefault();
     event.stopPropagation();
 
@@ -195,26 +197,7 @@ function updateUserOrgType() {
     );
 }
 
-// onLoad events
-document.addEventListener("DOMContentLoaded", (/*event*/) => {
-    jQuery("#users-table").DataTable({
-        "stateSave": true,
-        "responsive": true,
-        "lengthMenu": [
-            [-1, 5, 10, 25, 50],
-            ["All", 5, 10, 25, 50]
-        ],
-        "pageLength": -1, // Default show all
-        "columnDefs": [{
-            "targets": [1, 2],
-            "type": "date-iso"
-        }, {
-            "targets": 6,
-            "searchable": false,
-            "orderable": false
-        }]
-    });
-
+function initUserTable() {
     // Color all the org buttons per type
     document.querySelectorAll("button[data-vw-org-type]").forEach(function(e) {
         const orgType = ORG_TYPES[e.dataset.vwOrgType];
@@ -222,7 +205,6 @@ document.addEventListener("DOMContentLoaded", (/*event*/) => {
         e.title = orgType.name;
     });
 
-    // Add click events for user actions
     document.querySelectorAll("button[vw-remove2fa]").forEach(btn => {
         btn.addEventListener("click", remove2fa);
     });
@@ -239,8 +221,51 @@ document.addEventListener("DOMContentLoaded", (/*event*/) => {
         btn.addEventListener("click", enableUser);
     });
 
-    document.getElementById("updateRevisions").addEventListener("click", updateRevisions);
-    document.getElementById("reload").addEventListener("click", reload);
-    document.getElementById("userOrgTypeForm").addEventListener("submit", updateUserOrgType);
-    document.getElementById("inviteUserForm").addEventListener("submit", inviteUser);
+    if (jdenticon) {
+        jdenticon();
+    }
+}
+
+// onLoad events
+document.addEventListener("DOMContentLoaded", (/*event*/) => {
+    jQuery("#users-table").DataTable({
+        "drawCallback": function() {
+            initUserTable();
+        },
+        "stateSave": true,
+        "responsive": true,
+        "lengthMenu": [
+            [-1, 2, 5, 10, 25, 50],
+            ["All", 2, 5, 10, 25, 50]
+        ],
+        "pageLength": 2, // Default show all
+        "columnDefs": [{
+            "targets": [1, 2],
+            "type": "date-iso"
+        }, {
+            "targets": 6,
+            "searchable": false,
+            "orderable": false
+        }]
+    });
+
+    // Add click events for user actions
+    initUserTable();
+
+    const btnUpdateRevisions = document.getElementById("updateRevisions");
+    if (btnUpdateRevisions) {
+        btnUpdateRevisions.addEventListener("click", updateRevisions);
+    }
+    const btnReload = document.getElementById("reload");
+    if (btnReload) {
+        btnReload.addEventListener("click", reload);
+    }
+    const btnUserOrgTypeForm = document.getElementById("userOrgTypeForm");
+    if (btnUserOrgTypeForm) {
+        btnUserOrgTypeForm.addEventListener("submit", updateUserOrgType);
+    }
+    const btnInviteUserForm = document.getElementById("inviteUserForm");
+    if (btnInviteUserForm) {
+        btnInviteUserForm.addEventListener("submit", inviteUser);
+    }
 });