Validate user permissions again

Fixes #64

manifest.json

@@ -46,6 +46,7 @@
             "src/content/dropdown.js",
             "src/content/postpone.js",
             "src/content/sorting.js",
+            "src/content/permissionCheck.js",
             "src/content/content.js"
         ]
     }],

src/background/background.js

@@ -4,6 +4,17 @@ import { reportError } from '../util/errorReporting.js';
 import { getMessages, triggerMessageUpdate } from '../util/messages.js';
 import { getCustomSortIndex, getPostponeAction, getPrefix, setCustomSortIndex, setPopupMessage } from '../util/storage.js';
 
+/**
+ * @type {{
+ *      user?: string;
+ *      value: boolean;
+ * }}
+ */
+let permissionCache = {
+    user: undefined,
+    value: false,
+};
+
 (async () => {
     await setPopupMessage(undefined);
 
@@ -26,6 +37,14 @@ import { getCustomSortIndex, getPostponeAction, getPrefix, setCustomSortIndex, s
             case 'set-custom-sort-index':
                 await setCustomSortIndex(message.index);
                 return;
+            case 'get-permission-cache':
+                return permissionCache;
+            case 'set-permission-cache':
+                permissionCache = {
+                    user: message.user,
+                    value: message.value
+                };
+                return;
             case 'show-error':
                 console.error(`Received error message: ${message.errorMessage}`);
                 await showErrorBadge(message.errorMessage);

src/content/content.js

@@ -11,8 +11,7 @@ function init() {
                 modifyWikifield(
                     element,
                     element.getAttribute('issue-key').split('-')[0].toLowerCase(),
-                    editorCount++,
-                    !isVolunteerUser()
+                    editorCount++
                 );
             } catch (error) {
                 await sendErrorMessage(error);
@@ -49,6 +48,12 @@ function init() {
 }
 
 (async () => {
+    try {
+        userIsVolunteer = await queryPermissions();
+    } catch (error) {
+        await sendErrorMessage(error);
+    }
+
     try {
         const messagesReply = await browser.runtime.sendMessage({ id: 'messages-request' });
         categories = messagesReply.categories;

src/content/dropdown.js

@@ -176,6 +176,7 @@ function getMessageButton(editorCount, disabled) {
  * @param {HTMLTextAreaElement} textArea The text area that this dropdown is for
  * @param {string} project The project the current ticket is in
  * @param {number} editorCount A unique identifier for this wikifield
+ * @param {disabled} disabled Whether the dropdown button is disabled
  * 
  * @returns {boolean} Whether the dropdown could be successfully added
  */
@@ -206,7 +207,9 @@ function addDropdownToWikifield(element, textArea, project, editorCount, disable
  * @param {string} project The project the current ticket is in
  * @param {number} editorCount A unique identifier for this wikifield
  */
-function modifyWikifield(element, project, editorCount, disabled) {
+function modifyWikifield(element, project, editorCount) {
+    const disabled = !userIsVolunteer;
+
     element.classList.add('mojira-helper-messages-field');
 
     var textArea = element.querySelector('textarea');

src/content/permissionCheck.js

@@ -0,0 +1,84 @@
+const permissionCheckError = 'An error occurred while trying to validate Mojira permissions.\n';
+
+/**
+ * Parses the JSON response and checks if the currently logged-in user is in a user group other than `users`.
+ * @param {string} response The API response, hopefully in JSON format
+ * 
+ * @returns {boolean} whether the user is in at least one non-`users` group
+ * @throws {string} if there's no valid JSON or the JSON does not follow the API scheme.
+ */
+function parsePermissionResponse(response) {
+    try {
+        const json = JSON.parse(response);
+
+        const groups = json.groups?.items;
+        if (!groups) throw 'The API response is malformed and does not include groups.';
+
+        return groups.filter(group => group.name !== 'users').length > 0;
+    } catch (error) {
+        if (error instanceof SyntaxError) {
+            throw `${permissionCheckError}The server returned invalid JSON: ${error.message}`;
+        } else {
+            throw `${permissionCheckError}${error}`;
+        }
+    }
+}
+
+/**
+ * Checks if the currently logged in user is a volunteer user (moderator / helper).
+ *
+ * @returns {Promise<boolean>} true is the logged in user is a helper+, false otherwise.
+ * @throws {string} if an error occurs
+ */
+function queryPermissions() {
+    return new Promise(async (resolve, reject) => {
+        const httpRequest = new XMLHttpRequest();
+        httpRequest.onreadystatechange = async () => {
+            if (httpRequest.readyState === XMLHttpRequest.DONE) {
+                if (httpRequest.status === 200) {
+                    try {
+                        const perm = parsePermissionResponse(httpRequest.responseText);
+                        resolve(perm);
+                    } catch (error) {
+                        reject(error);
+                    }
+                }
+                reject(
+                    `${permissionCheckError}The server returned status code ${httpRequest.status} ${httpRequest.statusText}.`
+                );
+            }
+        }
+
+        try {
+            httpRequest.open('GET', 'https://bugs.mojang.com/rest/api/2/myself?expand=groups');
+            httpRequest.send();
+        } catch (error) {
+            reject(`${permissionCheckError}${error}`);
+        }
+    });
+}
+
+/**
+ * Checks if the currently logged in user is a volunteer user (moderator / helper).
+ * Uses the value from the cache unless the user name has changed.
+ * 
+ * @returns {Promise<boolean>} true if the logged in user is a helper+, false otherwise.
+ * @throws {string} if an error occurr.
+ */
+async function validatePermissions() {
+    const userName = document.querySelector('meta[name=ajs-remote-user]')?.attributes?.getNamedItem('content')?.value;
+
+    if (!userName) {
+        await browser.runtime.sendMessage({ id: 'set-permission-cache', user: undefined, value: false });
+        return false;
+    }
+
+    const permissionCache = await browser.runtime.sendMessage({ id: 'get-permission-cache' });
+    if (permissionCache.user === userName) {
+        return permissionCache.value;
+    }
+
+    const userPermissions = queryPermissions();
+    await browser.runtime.sendMessage({ id: 'set-permission-cache', user: userName, value: userPermissions });
+    return userPermissions;
+}

src/content/styling.css

@@ -3,11 +3,6 @@
     border-radius: 0 !important;
 }
 
-.mojira-helper-messages-textarea-disabled {
-    border: 1px solid #cc2e2e !important;
-    border-radius: 0 !important;
-}
-
 .mojira-helper-messages-textarea-shortcut-only {
     border: 1px solid #cc722e !important;
 }

src/content/util.js

@@ -14,12 +14,3 @@ async function sendErrorMessage(error) {
         console.error('Error while reporting error message:', err);
     }
 }
-
-/**
- * Checks if the currently logged in user is a volunteer user (moderator / helper), only works on issue pages
- * @returns {Boolean} true if the logged in user is a helper+, false otherwise
- */
-function isVolunteerUser() {
-    let opsbar = document.querySelector('div#opsbar-opsbar-transitions');
-    return opsbar && opsbar.children.length > 0;
-}

src/content/vars.js

@@ -54,3 +54,6 @@ let postponeAction = 'none';
 
 /** @type {number} */
 let customSortIndex = 0;
+
+/** @type {boolean} */
+let userIsVolunteer = false;