client/auth: show errors early in controllers

In other words, verify the privileges client-side before issuing an
request to the server. This commit focuses on routing (e.g. clicking a
link while not logged in), rather than DOM element visibility that
should be already taken care of.

client/js/controllers/comments_controller.js

@@ -6,11 +6,19 @@ const PostList = require('../models/post_list.js');
 const topNavigation = require('../models/top_navigation.js');
 const PageController = require('../controllers/page_controller.js');
 const CommentsPageView = require('../views/comments_page_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 const fields = ['id', 'comments', 'commentCount', 'thumbnailUrl'];
 
 class CommentsController {
     constructor(ctx) {
+        if (!api.hasPrivilege('comments:list')) {
+            this._view = new EmptyView();
+            this._view.showError(
+                'You don\'t have privileges to view comments.');
+            return;
+        }
+
         topNavigation.activate('comments');
         topNavigation.setTitle('Listing comments');
 

client/js/controllers/post_controller.js

@@ -13,6 +13,12 @@ const EmptyView = require('../views/empty_view.js');
 
 class PostController {
     constructor(id, editMode, ctx) {
+        if (!api.hasPrivilege('posts:view')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view posts.');
+            return;
+        }
+
         topNavigation.activate('posts');
         topNavigation.setTitle('Post #' + id.toString());
 

client/js/controllers/post_list_controller.js

@@ -8,6 +8,7 @@ const topNavigation = require('../models/top_navigation.js');
 const PageController = require('../controllers/page_controller.js');
 const PostsHeaderView = require('../views/posts_header_view.js');
 const PostsPageView = require('../views/posts_page_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 const fields = [
     'id', 'thumbnailUrl', 'type',
@@ -15,6 +16,12 @@ const fields = [
 
 class PostListController {
     constructor(ctx) {
+        if (!api.hasPrivilege('posts:list')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view posts.');
+            return;
+        }
+
         topNavigation.activate('posts');
         topNavigation.setTitle('Listing posts');
 

client/js/controllers/post_upload_controller.js

@@ -1,13 +1,21 @@
 'use strict';
 
+const api = require('../api.js');
 const router = require('../router.js');
 const misc = require('../util/misc.js');
 const topNavigation = require('../models/top_navigation.js');
 const Post = require('../models/post.js');
 const PostUploadView = require('../views/post_upload_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 class PostUploadController {
     constructor() {
+        if (!api.hasPrivilege('posts:create')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to upload posts.');
+            return;
+        }
+
         topNavigation.activate('upload');
         topNavigation.setTitle('Upload');
         this._view = new PostUploadView();

client/js/controllers/snapshots_controller.js

@@ -6,9 +6,16 @@ const SnapshotList = require('../models/snapshot_list.js');
 const PageController = require('../controllers/page_controller.js');
 const topNavigation = require('../models/top_navigation.js');
 const SnapshotsPageView = require('../views/snapshots_page_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 class SnapshotsController {
     constructor(ctx) {
+        if (!api.hasPrivilege('snapshots:list')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view history.');
+            return;
+        }
+
         topNavigation.activate('');
         topNavigation.setTitle('History');
 

client/js/controllers/tag_categories_controller.js

@@ -9,6 +9,13 @@ const EmptyView = require('../views/empty_view.js');
 
 class TagCategoriesController {
     constructor() {
+        if (!api.hasPrivilege('tagCategories:list')) {
+            this._view = new EmptyView();
+            this._view.showError(
+                'You don\'t have privileges to view tag categories.');
+            return;
+        }
+
         topNavigation.activate('tags');
         topNavigation.setTitle('Listing tags');
         TagCategoryList.get().then(response => {

client/js/controllers/tag_controller.js

@@ -11,6 +11,12 @@ const EmptyView = require('../views/empty_view.js');
 
 class TagController {
     constructor(ctx, section) {
+        if (!api.hasPrivilege('tags:view')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view tags.');
+            return;
+        }
+
         Tag.get(ctx.parameters.name).then(tag => {
             topNavigation.activate('tags');
             topNavigation.setTitle('Tag #' + tag.names[0]);

client/js/controllers/tag_list_controller.js

@@ -7,12 +7,19 @@ const topNavigation = require('../models/top_navigation.js');
 const PageController = require('../controllers/page_controller.js');
 const TagsHeaderView = require('../views/tags_header_view.js');
 const TagsPageView = require('../views/tags_page_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 const fields = [
     'names', 'suggestions', 'implications', 'lastEditTime', 'usages'];
 
 class TagListController {
     constructor(ctx) {
+        if (!api.hasPrivilege('tags:list')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view tags.');
+            return;
+        }
+
         topNavigation.activate('tags');
         topNavigation.setTitle('Listing tags');
 

client/js/controllers/user_controller.js

@@ -12,12 +12,20 @@ const EmptyView = require('../views/empty_view.js');
 
 class UserController {
     constructor(ctx, section) {
-        topNavigation.setTitle('User ' + ctx.parameters.name);
+        const userName = ctx.parameters.name;
-        User.get(ctx.parameters.name).then(user => {
+        if (!api.hasPrivilege('users:view') &&
+                !api.isLoggedIn({name: userName})) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view users.');
+            return;
+        }
+
+        topNavigation.setTitle('User ' + userName);
+        User.get(userName).then(user => {
             const isLoggedIn = api.isLoggedIn(user);
             const infix = isLoggedIn ? 'self' : 'any';
 
-            this._name = ctx.parameters.name;
+            this._name = userName;
             user.addEventListener('change', e => this._evtSaved(e));
 
             const myRankIndex = api.user ?

client/js/controllers/user_list_controller.js

@@ -7,9 +7,16 @@ const topNavigation = require('../models/top_navigation.js');
 const PageController = require('../controllers/page_controller.js');
 const UsersHeaderView = require('../views/users_header_view.js');
 const UsersPageView = require('../views/users_page_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 class UserListController {
     constructor(ctx) {
+        if (!api.hasPrivilege('users:list')) {
+            this._view = new EmptyView();
+            this._view.showError('You don\'t have privileges to view users.');
+            return;
+        }
+
         topNavigation.activate('users');
         topNavigation.setTitle('Listing users');
 

client/js/controllers/user_registration_controller.js

@@ -5,9 +5,16 @@ const api = require('../api.js');
 const User = require('../models/user.js');
 const topNavigation = require('../models/top_navigation.js');
 const RegistrationView = require('../views/registration_view.js');
+const EmptyView = require('../views/empty_view.js');
 
 class UserRegistrationController {
     constructor() {
+        if (!api.hasPrivilege('users:create')) {
+            this._view = new EmptyView();
+            this._view.showError('Registration is closed.');
+            return;
+        }
+
         topNavigation.activate('register');
         topNavigation.setTitle('Registration');
         this._view = new RegistrationView();