Merged our two maintenance middleware into one

- Reduced our maintenance middleware code down to the bare minimum!
  - We have an old maintenance middleware in place to handle when a site is forcibly put into maintenance mode, or the urlService hasn't finished booting
    - This maintenance middleware was mounted on every sub app, instead of globally for reasons I no longer remember
  - Recently, we introduced a new, static version of maintenence middleware to show during the boot process so we can get the server started earlier & not drop requests
    - This version has its own HTML template and doesn't depend on any of Ghost's error rendering code
  - To simplify and help with decoupling, this commit merges the two middleware, so that the new independent & static middleware renders its template for any one of the 3 possible maintenance modes
    - It only needs to exist in the top level app 🙌

TODO: move the maintenance middleware to its own file/package so it's not part of the app.js as that is weird

core/app.js

@@ -1,14 +1,25 @@
 const sentry = require('./shared/sentry');
 const express = require('./shared/express');
+const config = require('./shared/config');
+const urlService = require('./server/services/url');
 
 const fs = require('fs');
 const path = require('path');
 
+const isMaintenanceModeEnabled = (req) => {
+    if (req.app.get('maintenance') || config.get('maintenance').enabled || !urlService.hasFinished()) {
+        return true;
+    }
+
+    return false;
+};
+
 // We never want middleware functions to be anonymous
 const maintenanceMiddleware = (req, res, next) => {
-    if (!req.app.get('maintenance')) {
+    if (!isMaintenanceModeEnabled(req)) {
         return next();
     }
+
     res.set({
         'Cache-Control': 'no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0'
     });

core/boot.js

@@ -96,8 +96,8 @@ async function initCore({ghostServer, config, bootLogger, frontend}) {
     debug('Begin: Url Service');
     const urlService = require('./server/services/url');
     // Note: there is no await here, we do not wait for the url service to finish
-    // We can return, but the site will remain in (the shared, not global) maintenance mode until this finishes
-    // This is managed on request: https://github.com/TryGhost/Ghost/blob/main/core/server/web/shared/middleware/maintenance.js#L13
+    // We can return, but the site will remain in maintenance mode until this finishes
+    // This is managed on request: https://github.com/TryGhost/Ghost/blob/main/core/app.js#L10
     urlService.init({
         onFinished: () => {
             bootLogger.log('URL Service Ready');

core/frontend/web/site.js

@@ -153,9 +153,6 @@ module.exports = function setupSiteApp(options = {}) {
     sitemapHandler(siteApp);
     debug('Internal apps done');
 
-    // send 503 error page in case of maintenance
-    siteApp.use(shared.middleware.maintenance);
-
     // Add in all trailing slashes & remove uppercase
     // must happen AFTER asset loading and BEFORE routing
     siteApp.use(shared.middleware.prettyUrls);

core/server/web/admin/app.js

@@ -26,9 +26,6 @@ module.exports = function setupAdminApp() {
         });
     }
 
-    // Render error page in case of maintenance
-    adminApp.use(shared.middleware.maintenance);
-
     // Force SSL if required
     // must happen AFTER asset loading and BEFORE routing
     adminApp.use(shared.middleware.urlRedirects.adminSSLAndHostRedirect);

core/server/web/api/canary/admin/app.js

@@ -19,9 +19,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // Check version matches for API requests, depends on res.locals.safeVersion being set
     // Therefore must come after themeHandler.ghostLocals, for now
     apiApp.use(apiMw.versionMatch);

core/server/web/api/canary/content/app.js

@@ -17,9 +17,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // API shouldn't be cached
     apiApp.use(shared.middleware.cacheControl('private'));
 

core/server/web/api/v2/admin/app.js

@@ -19,9 +19,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // Check version matches for API requests, depends on res.locals.safeVersion being set
     // Therefore must come after themeHandler.ghostLocals, for now
     apiApp.use(apiMw.versionMatch);

core/server/web/api/v2/content/app.js

@@ -17,9 +17,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // API shouldn't be cached
     apiApp.use(shared.middleware.cacheControl('private'));
 

core/server/web/api/v3/admin/app.js

@@ -19,9 +19,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // Check version matches for API requests, depends on res.locals.safeVersion being set
     // Therefore must come after themeHandler.ghostLocals, for now
     apiApp.use(apiMw.versionMatch);

core/server/web/api/v3/content/app.js

@@ -17,9 +17,6 @@ module.exports = function setupApiApp() {
     // Query parsing
     apiApp.use(boolParser());
 
-    // send 503 json response in case of maintenance
-    apiApp.use(shared.middleware.maintenance);
-
     // API shouldn't be cached
     apiApp.use(shared.middleware.cacheControl('private'));
 

core/server/web/members/app.js

@@ -13,9 +13,6 @@ module.exports = function setupMembersApp() {
     debug('Members App setup start');
     const membersApp = express('members');
 
-    // send 503 json response in case of maintenance
-    membersApp.use(shared.middleware.maintenance);
-
     // Members API shouldn't be cached
     membersApp.use(shared.middleware.cacheControl('private'));
 

core/server/web/oauth/app.js

@@ -2,7 +2,6 @@ const debug = require('@tryghost/debug')('web:oauth:app');
 const {URL} = require('url');
 const express = require('../../../shared/express');
 const urlUtils = require('../../../shared/url-utils');
-const shared = require('../shared');
 const settingsCache = require('../../../shared/settings-cache');
 const models = require('../../models');
 const auth = require('../../services/auth');
@@ -24,9 +23,6 @@ module.exports = function setupOAuthApp() {
     }
     oauthApp.use(labsMiddleware);
 
-    // send 503 json response in case of maintenance
-    oauthApp.use(shared.middleware.maintenance);
-
     /**
      * Configure the passport.authenticate middleware
      * We need to configure it on each request because clientId and secret

core/server/web/shared/middleware/index.js

@@ -15,10 +15,6 @@ module.exports = {
         return require('./error-handler');
     },
 
-    get maintenance() {
-        return require('./maintenance');
-    },
-
     get prettyUrls() {
         return require('./pretty-urls');
     },

core/server/web/shared/middleware/maintenance.js

@@ -1,25 +0,0 @@
-const errors = require('@tryghost/errors');
-const config = require('../../../../shared/config');
-const tpl = require('@tryghost/tpl');
-const urlService = require('../../../services/url');
-
-const messages = {
-    maintenance: 'Site is currently undergoing maintenance, please wait a moment then retry.',
-    maintenanceUrlService: 'Site is starting up, please wait a moment then retry.'
-};
-
-module.exports = function maintenance(req, res, next) {
-    if (config.get('maintenance').enabled) {
-        return next(new errors.MaintenanceError({
-            message: tpl(messages.maintenance)
-        }));
-    }
-
-    if (!urlService.hasFinished()) {
-        return next(new errors.MaintenanceError({
-            message: tpl(messages.maintenanceUrlService)
-        }));
-    }
-
-    next();
-};