FEATURE: detect when client thinks user is logged on but is not

This cleans up an error condition where UI thinks a user is logged on
but the user is not. If this happens user will be prompted to refresh.

app/assets/javascripts/application.js

@@ -11,6 +11,7 @@
 // Stuff we need to load first
 //= require ./discourse/lib/utilities
 //= require ./discourse/lib/page-visible
+//= require ./discourse/lib/logout
 //= require ./discourse/lib/ajax
 //= require ./discourse/lib/text
 //= require ./discourse/lib/hash

app/assets/javascripts/discourse/initializers/logout.js.es6

@@ -1,5 +1,7 @@
 import logout from 'discourse/lib/logout';
 
+let _showingLogout = false;
+
 //  Subscribe to "logout" change events via the Message Bus
 export default {
   name: "logout",
@@ -7,14 +9,22 @@ export default {
 
   initialize: function (container) {
     const messageBus = container.lookup('message-bus:main');
-    const siteSettings = container.lookup('site-settings:main');
-    const keyValueStore = container.lookup('key-value-store:main');
 
     if (!messageBus) { return; }
-    const callback = () => logout(siteSettings, keyValueStore);
 
     messageBus.subscribe("/logout", function () {
-      bootbox.dialog(I18n.t("logout"), {label: I18n.t("refresh"), callback}, {onEscape: callback, backdrop: 'static'});
+      if (!_showingLogout) {
+
+        _showingLogout = true;
+
+        bootbox.dialog(I18n.t("logout"), {
+          label: I18n.t("refresh"),
+          callback: logout
+        }, {
+          onEscape: logout,
+          backdrop: 'static'
+        });
+      }
     });
   }
 };

app/assets/javascripts/discourse/lib/ajax.js.es6

@@ -1,7 +1,9 @@
 import pageVisible from 'discourse/lib/page-visible';
+import logout from 'discourse/lib/logout';
 
 let _trackView = false;
 let _transientHeader = null;
+let _showingLogout = false;
 
 export function setTransientHeader(key, value) {
   _transientHeader = {key, value};
@@ -39,6 +41,10 @@ export function ajax() {
 
     args.headers = args.headers || {};
 
+    if (Discourse.__container__.lookup('current-user:main')) {
+      args.headers['Discourse-Logged-In'] = "true";
+    }
+
     if (_transientHeader) {
       args.headers[_transientHeader.key] = _transientHeader.value;
       _transientHeader = null;
@@ -54,7 +60,22 @@ export function ajax() {
       args.headers['Discourse-Visible'] = "true";
     }
 
+    let handleLogoff = function(xhr) {
+      if (xhr.getResponseHeader('Discourse-Logged-Out') && !_showingLogout) {
+        _showingLogout = true;
+        bootbox.dialog(
+          I18n.t("logout"), {label: I18n.t("refresh"), callback: logout},
+          {
+            onEscape: () => logout(),
+            backdrop: 'static'
+          }
+        );
+      }
+    };
+
     args.success = (data, textStatus, xhr) => {
+      handleLogoff(xhr);
+
       if (xhr.getResponseHeader('Discourse-Readonly')) {
         Ember.run(() => Discourse.Site.currentProp('isReadOnly', true));
       }
@@ -67,6 +88,8 @@ export function ajax() {
     };
 
     args.error = (xhr, textStatus, errorThrown) => {
+      handleLogoff(xhr);
+
       // note: for bad CSRF we don't loop an extra request right away.
       //  this allows us to eliminate the possibility of having a loop.
       if (xhr.status === 403 && xhr.responseText === "[\"BAD CSRF\"]") {

app/assets/javascripts/discourse/lib/logout.js.es6

@@ -1,4 +1,10 @@
 export default function logout(siteSettings, keyValueStore) {
+  if (!siteSettings || !keyValueStore) {
+    const container = Discourse.__container__;
+    siteSettings = siteSettings || container.lookup('site-settings:main');
+    keyValueStore = keyValueStore || container.lookup('key-value-store:main');
+  }
+
   keyValueStore.abandonLocal();
 
   const redirect = siteSettings.logout_redirect;

config/initializers/004-message_bus.rb

@@ -22,13 +22,18 @@ def setup_message_bus_env(env)
       user.groups.pluck('groups.id')
     end
 
+    extra_headers = {
+      "Access-Control-Allow-Origin" => Discourse.base_url_no_prefix,
+      "Access-Control-Allow-Methods" => "GET, POST",
+      "Access-Control-Allow-Headers" => "X-SILENCE-LOGGER, X-Shared-Session-Key, Dont-Chunk, Discourse-Visible"
+    }
+
+    if env[Auth::DefaultCurrentUserProvider::BAD_TOKEN]
+      extra_headers['Discourse-Logged-Out'] = '1'
+    end
+
     hash = {
-      extra_headers:
+      extra_headers: extra_headers,
-        {
-          "Access-Control-Allow-Origin" => Discourse.base_url_no_prefix,
-          "Access-Control-Allow-Methods" => "GET, POST",
-          "Access-Control-Allow-Headers" => "X-SILENCE-LOGGER, X-Shared-Session-Key, Dont-Chunk, Discourse-Visible"
-        },
       user_id: user_id,
       group_ids: group_ids,
       is_admin: is_admin,

lib/auth/default_current_user_provider.rb

@@ -14,6 +14,7 @@ class Auth::DefaultCurrentUserProvider
   TOKEN_COOKIE ||= "_t"
   PATH_INFO ||= "PATH_INFO"
   COOKIE_ATTEMPTS_PER_MIN ||= 10
+  BAD_TOKEN ||= "_DISCOURSE_BAD_TOKEN"
 
   # do all current user initialization here
   def initialize(env)
@@ -58,7 +59,8 @@ class Auth::DefaultCurrentUserProvider
         current_user = @user_token.try(:user)
       end
 
-      unless current_user
+      if !current_user
+        @env[BAD_TOKEN] = true
         begin
           limiter.performed!
         rescue RateLimiter::LimitExceeded
@@ -69,6 +71,8 @@ class Auth::DefaultCurrentUserProvider
           )
         end
       end
+    elsif @env['HTTP_DISCOURSE_LOGGED_IN']
+      @env[BAD_TOKEN] = true
     end
 
     if current_user && should_update_last_seen?

lib/hijack.rb

@@ -78,6 +78,10 @@ module Hijack
           headers['Content-Length'] = body.bytesize
           headers['Connection'] = "close"
 
+          if env[Auth::DefaultCurrentUserProvider::BAD_TOKEN]
+            headers['Discourse-Logged-Out'] = '1'
+          end
+
           status_string = Rack::Utils::HTTP_STATUS_CODES[response.status.to_i] || "Unknown"
           io.write "#{response.status} #{status_string}\r\n"
 

lib/middleware/request_tracker.rb

@@ -169,6 +169,11 @@ class Middleware::RequestTracker
     if info && (headers = result[1])
       headers["X-Runtime"] = "%0.6f" % info[:total_duration]
     end
+
+    if env[Auth::DefaultCurrentUserProvider::BAD_TOKEN] && (headers = result[1])
+      headers['Discourse-Logged-Out'] = '1'
+    end
+
     result
   ensure
     if (limiters = env['DISCOURSE_RATE_LIMITERS']) && env['DISCOURSE_IS_ASSET_PATH']

spec/requests/session_controller_spec.rb

@@ -182,4 +182,17 @@ RSpec.describe SessionController do
       end
     end
   end
+
+  context 'logoff support' do
+    it 'can log off users cleanly' do
+      user = Fabricate(:user)
+      sign_in(user)
+
+      UserAuthToken.destroy_all
+
+      # we need a route that will call current user
+      post '/draft.json', params: {}
+      expect(response.headers['Discourse-Logged-Out']).to eq("1")
+    end
+  end
 end