Fixed default feedback enabled when flag is disabled (#15660)

fixes https://github.com/TryGhost/Team/issues/2114
fixes https://github.com/TryGhost/Team/issues/2115

When a new newsletter is created, the frontend will send feedback_enabled to true. We'll catch this in the backend and don't allow setting feedback_enabled to true when audience_feedback flag is disabled. This is also handled for editing newsletters.

To fix this in existing sites, I added a migration that disables feedback for all sites (since this is an alpha feature). Once we'll release the feature later, it will be disabled for existing newsletters, just like expected.

ghost/core/core/server/data/migrations/versions/5.21/2022-10-24-07-23-disable-feedback-enabled.js

@@ -0,0 +1,20 @@
+const logging = require('@tryghost/logging');
+const {createTransactionalMigration} = require('../../utils');
+
+module.exports = createTransactionalMigration(
+    async function up(connection) {
+        const affectedRows = await connection('newsletters')
+            .update({
+                feedback_enabled: false
+            })
+            .where('feedback_enabled', true);
+
+        if (affectedRows > 0) {
+            // Only log if this site was affected by the issue.
+            logging.info(`Disabled feedback for ${affectedRows} newsletter(s)`);
+        }
+    },
+    async function down() {
+        // no-op: we don't need to change it back
+    }
+);

ghost/core/core/server/services/newsletters/index.js

@@ -4,6 +4,7 @@ const mail = require('../mail');
 const models = require('../../models');
 const urlUtils = require('../../../shared/url-utils');
 const limitService = require('../limits');
+const labs = require('../../../shared/labs');
 
 const MAGIC_LINK_TOKEN_VALIDITY = 24 * 60 * 60 * 1000;
 
@@ -13,5 +14,6 @@ module.exports = new NewslettersService({
     mail,
     singleUseTokenProvider: new SingleUseTokenProvider(models.SingleUseToken, MAGIC_LINK_TOKEN_VALIDITY),
     urlUtils,
-    limitService
+    limitService,
+    labs
 });

ghost/core/core/server/services/newsletters/service.js

@@ -21,13 +21,16 @@ class NewslettersService {
      * @param {Object} options.singleUseTokenProvider
      * @param {Object} options.urlUtils
      * @param {ILimitService} options.limitService
+     * @param {Object} options.labs
      */
-    constructor({NewsletterModel, MemberModel, mail, singleUseTokenProvider, urlUtils, limitService}) {
+    constructor({NewsletterModel, MemberModel, mail, singleUseTokenProvider, urlUtils, limitService, labs}) {
         this.NewsletterModel = NewsletterModel;
         this.MemberModel = MemberModel;
         this.urlUtils = urlUtils;
         /** @private */
         this.limitService = limitService;
+        /** @private */
+        this.labs = labs;
 
         /* email verification setup */
 
@@ -251,6 +254,13 @@ class NewslettersService {
             }
         }
 
+        if (cleanedAttrs.feedback_enabled) {
+            if (!this.labs.isSet('audienceFeedback')) {
+                // Not allowed to set to true
+                cleanedAttrs.feedback_enabled = false;
+            }
+        }
+
         return {cleanedAttrs, emailsToVerify};
     }