Added well known recommendations service (#17895)

fixes https://github.com/TryGhost/Product/issues/3797 fixes https://github.com/TryGhost/Product/issues/3776 fixes https://github.com/TryGhost/Product/issues/3798 - Added support for storing json webmentions - Improved handling deleted webmentions (set deleted to true instead of verified to false)
2024-12-23 10:53:34 +03:00 · 2023-08-31 16:57:18 +02:00 · 2023-08-31 16:57:18 +02:00 · 96fefaea69
commit 96fefaea69
parent e97b71dc52
21 changed files with 338 additions and 77 deletions
--- a/ghost/core/core/frontend/web/middleware/serve-public-file.js
+++ b/ghost/core/core/frontend/web/middleware/serve-public-file.js
@ -26,7 +26,7 @@ function matchCacheKey(req, cache) {
    return true;
 }

-function createPublicFileMiddleware(location, file, mime, maxAge) {
+function createPublicFileMiddleware(location, file, mime, maxAge, options = {}) {
    let cache;
    // These files are provided by Ghost, and therefore live inside of the core folder
    const staticFilePath = config.get('paths').publicFilePath;
@ -45,7 +45,7 @@ function createPublicFileMiddleware(location, file, mime, maxAge) {
        }

        // send image files directly and let express handle content-length, etag, etc
-        if (mime.match(/^image/)) {
+        if (mime.match(/^image/) || options.disableServerCache) {
            return res.sendFile(filePath, (err) => {
                if (err && err.status === 404) {
                    // ensure we're triggering basic asset 404 and not a templated 404
@ -101,8 +101,8 @@ function createPublicFileMiddleware(location, file, mime, maxAge) {

 // ### servePublicFile Middleware
 // Handles requests to robots.txt and favicon.ico (and caches them)
-function servePublicFile(location, file, type, maxAge) {
-    const publicFileMiddleware = createPublicFileMiddleware(location, file, type, maxAge);
+function servePublicFile(location, file, type, maxAge, options = {}) {
+    const publicFileMiddleware = createPublicFileMiddleware(location, file, type, maxAge, options);

    return function servePublicFileMiddleware(req, res, next) {
        if (req.path === '/' + file) {
--- a/ghost/core/core/frontend/web/site.js
+++ b/ghost/core/core/frontend/web/site.js
@ -98,6 +98,9 @@ module.exports = function setupSiteApp(routerConfig) {
        (req, res, next) => membersService.api.middleware.wellKnown(req, res, next)
    );

+    // Recommendations well-known
+    siteApp.use(mw.servePublicFile('built', '.well-known/recommendations.json', 'application/json', config.get('caching:publicAssets:maxAge'), {disableServerCache: true}));
+
    // setup middleware for internal apps
    // @TODO: refactor this to be a proper app middleware hook for internal apps
    config.get('apps:internal').forEach((appName) => {
--- a/ghost/core/core/server/services/mentions/WebmentionMetadata.js
+++ b/ghost/core/core/server/services/mentions/WebmentionMetadata.js
@ -14,7 +14,8 @@ module.exports = class WebmentionMetadata {
            author: data.metadata.author,
            image: data.metadata.thumbnail ? new URL(data.metadata.thumbnail) : null,
            favicon: data.metadata.icon ? new URL(data.metadata.icon) : null,
-            body: data.body
+            body: data.body,
+            contentType: data.contentType
        };
        return result;
    }
--- a/ghost/core/core/server/services/mentions/service.js
+++ b/ghost/core/core/server/services/mentions/service.js
@ -28,6 +28,8 @@ module.exports = {
    /** @type {import('@tryghost/webmentions/lib/MentionsAPI')} */
    api: null,
    controller: new MentionController(),
+    /** @type {import('@tryghost/webmentions/lib/MentionSendingService')} */
+    sendingService: null,
    didInit: false,
    async init() {
        if (this.didInit) {
@ -107,5 +109,7 @@ module.exports = {
            }
        });
        sendingService.listen(events);
+
+        this.sendingService = sendingService;
    }
 };
--- a/ghost/core/core/server/services/recommendations/RecommendationServiceWrapper.js
+++ b/ghost/core/core/server/services/recommendations/RecommendationServiceWrapper.js
@ -19,15 +19,34 @@ class RecommendationServiceWrapper {
            return;
        }

-        const {InMemoryRecommendationRepository, RecommendationService, RecommendationController} = require('@tryghost/recommendations');
+        const config = require('../../../shared/config');
+        const urlUtils = require('../../../shared/url-utils');
+        const {InMemoryRecommendationRepository, RecommendationService, RecommendationController, WellknownService} = require('@tryghost/recommendations');
+
+        const mentions = require('../mentions');
+
+        if (!mentions.sendingService) {
+            // eslint-disable-next-line ghost/ghost-custom/no-native-error
+            throw new Error('MentionSendingService not intialized, but this is a dependency of RecommendationServiceWrapper. Check boot order.');
+        }
+
+        const wellknownService = new WellknownService({
+            dir: config.getContentPath('public'),
+            urlUtils
+        });

        this.repository = new InMemoryRecommendationRepository();
        this.service = new RecommendationService({
-            repository: this.repository
+            repository: this.repository,
+            wellknownService,
+            mentionSendingService: mentions.sendingService
        });
        this.controller = new RecommendationController({
            service: this.service
        });
+
+        // eslint-disable-next-line no-console
+        this.service.init().catch(console.error);
    }
 }

--- a/ghost/core/test/e2e-api/admin/snapshots/recommendations.test.js.snap
+++ b/ghost/core/test/e2e-api/admin/snapshots/recommendations.test.js.snap
@ -13,7 +13,7 @@ Object {
      "reason": "Because dogs are cute",
      "title": "Dog Pictures",
      "updated_at": null,
-      "url": "https://dogpictures.com",
+      "url": "https://dogpictures.com/",
    },
  ],
 }
@ -23,7 +23,7 @@ exports[`Recommendations Admin API Can add a full recommendation 2: [headers] 1`
 Object {
  "access-control-allow-origin": "http://127.0.0.1:2369",
  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
-  "content-length": "353",
+  "content-length": "354",
  "content-type": "application/json; charset=utf-8",
  "content-version": StringMatching /v\\\\d\\+\\\\\\.\\\\d\\+/,
  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
@ -47,7 +47,7 @@ Object {
      "reason": null,
      "title": "Dog Pictures",
      "updated_at": null,
-      "url": "https://dogpictures.com",
+      "url": "https://dogpictures.com/",
    },
  ],
 }
@ -57,7 +57,7 @@ exports[`Recommendations Admin API Can add a minimal recommendation 2: [headers]
 Object {
  "access-control-allow-origin": "http://127.0.0.1:2369",
  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
-  "content-length": "262",
+  "content-length": "263",
  "content-type": "application/json; charset=utf-8",
  "content-version": StringMatching /v\\\\d\\+\\\\\\.\\\\d\\+/,
  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
@ -113,7 +113,7 @@ Object {
      "reason": "Because dogs are cute",
      "title": "Dog Pictures",
      "updated_at": null,
-      "url": "https://dogpictures.com",
+      "url": "https://dogpictures.com/",
    },
  ],
 }
@ -123,7 +123,7 @@ exports[`Recommendations Admin API Can browse 2: [headers] 1`] = `
 Object {
  "access-control-allow-origin": "http://127.0.0.1:2369",
  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
-  "content-length": "353",
+  "content-length": "354",
  "content-type": "application/json; charset=utf-8",
  "content-version": StringMatching /v\\\\d\\+\\\\\\.\\\\d\\+/,
  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
@ -159,7 +159,7 @@ Object {
      "reason": "Because cats are cute",
      "title": "Cat Pictures",
      "updated_at": null,
-      "url": "https://catpictures.com",
+      "url": "https://catpictures.com/",
    },
  ],
 }
@ -169,7 +169,7 @@ exports[`Recommendations Admin API Can edit recommendation 2: [headers] 1`] = `
 Object {
  "access-control-allow-origin": "http://127.0.0.1:2369",
  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
-  "content-length": "354",
+  "content-length": "355",
  "content-type": "application/json; charset=utf-8",
  "content-version": StringMatching /v\\\\d\\+\\\\\\.\\\\d\\+/,
  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
--- a/ghost/core/test/e2e-api/admin/recommendations.test.js
+++ b/ghost/core/test/e2e-api/admin/recommendations.test.js
@ -46,7 +46,7 @@ describe('Recommendations Admin API', function () {

        // Check everything is set correctly
        assert.equal(body.recommendations[0].title, 'Dog Pictures');
-        assert.equal(body.recommendations[0].url, 'https://dogpictures.com');
+        assert.equal(body.recommendations[0].url, 'https://dogpictures.com/');
        assert.equal(body.recommendations[0].reason, null);
        assert.equal(body.recommendations[0].excerpt, null);
        assert.equal(body.recommendations[0].featured_image, null);
@ -84,7 +84,7 @@ describe('Recommendations Admin API', function () {

        // Check everything is set correctly
        assert.equal(body.recommendations[0].title, 'Dog Pictures');
-        assert.equal(body.recommendations[0].url, 'https://dogpictures.com');
+        assert.equal(body.recommendations[0].url, 'https://dogpictures.com/');
        assert.equal(body.recommendations[0].reason, 'Because dogs are cute');
        assert.equal(body.recommendations[0].excerpt, 'Dogs are cute');
        assert.equal(body.recommendations[0].featured_image, 'https://dogpictures.com/dog.jpg');
@ -123,7 +123,7 @@ describe('Recommendations Admin API', function () {
        // Check everything is set correctly
        assert.equal(body.recommendations[0].id, id);
        assert.equal(body.recommendations[0].title, 'Cat Pictures');
-        assert.equal(body.recommendations[0].url, 'https://catpictures.com');
+        assert.equal(body.recommendations[0].url, 'https://catpictures.com/');
        assert.equal(body.recommendations[0].reason, 'Because cats are cute');
        assert.equal(body.recommendations[0].excerpt, 'Cats are cute');
        assert.equal(body.recommendations[0].featured_image, 'https://catpictures.com/cat.jpg');
--- a/ghost/oembed-service/lib/OEmbedService.js
+++ b/ghost/oembed-service/lib/OEmbedService.js
@ -132,7 +132,7 @@ class OEmbedService {
    /**
     * @param {string} url
     *
-     * @returns {Promise<{url: string, body: string}>}
+     * @returns {Promise<{url: string, body: string, contentType: string|undefined}>}
     */
    async fetchPageHtml(url) {
        // Fetch url and get response as binary buffer to
@ -154,7 +154,8 @@ class OEmbedService {
            if (encoding === null) {
                return {
                    body: body.toString(),
-                    url: responseUrl
+                    url: responseUrl,
+                    contentType: headers['content-type']
                };
            }

@ -163,14 +164,16 @@ class OEmbedService {

            return {
                body: decodedBody,
-                url: responseUrl
+                url: responseUrl,
+                contentType: headers['content-type']
            };
        } catch (err) {
            logging.error(err);
            //return non decoded body anyway
            return {
                body: body.toString(),
-                url: responseUrl
+                url: responseUrl,
+                contentType: headers['content-type']
            };
        }
    }
@ -355,7 +358,7 @@ class OEmbedService {
            }

            // Not in the list, we need to fetch the content
-            const {url: pageUrl, body} = await this.fetchPageHtml(url);
+            const {url: pageUrl, body, contentType} = await this.fetchPageHtml(url);

            // fetch only bookmark when explicitly requested
            if (type === 'bookmark') {
@ -364,8 +367,26 @@ class OEmbedService {

            // mentions need to return bookmark data (metadata) and body (html) for link verification
            if (type === 'mention') {
+                if (contentType.includes('application/json')) {
+                    // No need to fetch metadata: we have none
+                    const bookmark = {
+                        version: '1.0',
+                        type: 'bookmark',
+                        url,
+                        metadata: {
+                            title: null,
+                            description: null,
+                            publisher: null,
+                            author: null,
+                            thumbnail: null,
+                            icon: null
+                        },
+                        contentType
+                    };
+                    return {...bookmark, body};
+                }
                const bookmark = await this.fetchBookmarkData(url, body);
-                return {...bookmark, body};
+                return {...bookmark, body, contentType};
            }

            // attempt to fetch oembed
--- a/ghost/recommendations/package.json
+++ b/ghost/recommendations/package.json
@ -22,12 +22,13 @@
    "build"
  ],
  "devDependencies": {
+    "@tryghost/errors": "1.2.24",
+    "@types/node": "^20.5.7",
    "c8": "8.0.1",
    "mocha": "10.2.0",
    "sinon": "15.2.0",
    "ts-node": "10.9.1",
-    "typescript": "5.2.2",
-    "@tryghost/errors": "1.2.24"
+    "typescript": "5.2.2"
  },
  "dependencies": {}
 }
--- a/ghost/recommendations/src/InMemoryRecommendationRepository.ts
+++ b/ghost/recommendations/src/InMemoryRecommendationRepository.ts
@ -9,7 +9,7 @@ export class InMemoryRecommendationRepository implements RecommendationRepositor
            excerpt: "The Pragmatic Programmer is one of those rare tech books you’ll read, re-read, and read again over the years. Whether you’re new to the field or an experienced practitioner, you’ll come away with fresh insights each and every time.",
            featuredImage: "https://www.thepragmaticprogrammer.com/image.png",
            favicon: "https://www.shesabeast.co/content/images/size/w256h256/2022/08/transparent-icon-black-copy-gray-bar.png",
-            url: "https://www.thepragmaticprogrammer.com/",
+            url: new URL("https://www.thepragmaticprogrammer.com/"),
            oneClickSubscribe: false
        }),
        new Recommendation({
@ -18,7 +18,7 @@ export class InMemoryRecommendationRepository implements RecommendationRepositor
            excerpt: "The Pragmatic Programmer is one of those rare tech books you’ll read, re-read, and read again over the years. Whether you’re new to the field or an experienced practitioner, you’ll come away with fresh insights each and every time.",
            featuredImage: "https://www.thepragmaticprogrammer.com/image.png",
            favicon: "https://substackcdn.com/image/fetch/f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fbucketeer-e05bbc84-baa3-437e-9518-adb32be77984.s3.amazonaws.com%2Fpublic%2Fimages%2Fc7cde267-8f9e-47fa-9aef-5be03bad95ed%2Fapple-touch-icon-1024x1024.png",
-            url: "https://www.thepragmaticprogrammer.com/",
+            url: new URL("https://www.thepragmaticprogrammer.com/"),
            oneClickSubscribe: false
        }),
        new Recommendation({
@ -27,7 +27,7 @@ export class InMemoryRecommendationRepository implements RecommendationRepositor
            excerpt: "The Pragmatic Programmer is one of those rare tech books you’ll read, re-read, and read again over the years. Whether you’re new to the field or an experienced practitioner, you’ll come away with fresh insights each and every time.",
            featuredImage: "https://www.thepragmaticprogrammer.com/image.png",
            favicon: "https://clickhole.com/wp-content/uploads/2020/05/cropped-clickhole-icon-180x180.png",
-            url: "https://www.thepragmaticprogrammer.com/",
+            url: new URL("https://www.thepragmaticprogrammer.com/"),
            oneClickSubscribe: false
        }),
        new Recommendation({
@ -36,7 +36,7 @@ export class InMemoryRecommendationRepository implements RecommendationRepositor
            excerpt: "The Pragmatic Programmer is one of those rare tech books you’ll read, re-read, and read again over the years. Whether you’re new to the field or an experienced practitioner, you’ll come away with fresh insights each and every time.",
            featuredImage: "https://www.thepragmaticprogrammer.com/image.png",
            favicon: "https://www.theverge.com/icons/apple_touch_icon.png",
-            url: "https://www.thepragmaticprogrammer.com/",
+            url: new URL("https://www.thepragmaticprogrammer.com/"),
            oneClickSubscribe: false
        }),
        new Recommendation({
@ -45,7 +45,7 @@ export class InMemoryRecommendationRepository implements RecommendationRepositor
            excerpt: "The Pragmatic Programmer is one of those rare tech books you’ll read, re-read, and read again over the years. Whether you’re new to the field or an experienced practitioner, you’ll come away with fresh insights each and every time.",
            featuredImage: "https://www.thepragmaticprogrammer.com/image.png",
            favicon: "https://substackcdn.com/image/fetch/w_96,h_96,c_fill,f_webp,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Ff3f2b2ad-681f-45e1-9496-db80f45e853d_403x403.png",
-            url: "https://www.thepragmaticprogrammer.com/",
+            url: new URL("https://www.thepragmaticprogrammer.com/"),
            oneClickSubscribe: true
        })
    ];
--- a/ghost/recommendations/src/Recommendation.ts
+++ b/ghost/recommendations/src/Recommendation.ts
@ -7,12 +7,12 @@ export class Recommendation {
    excerpt: string|null // Fetched from the site meta data
    featuredImage: string|null // Fetched from the site meta data
    favicon: string|null // Fetched from the site meta data
-    url: string
+    url: URL
    oneClickSubscribe: boolean
    createdAt: Date
    updatedAt: Date|null

-    constructor(data: {id?: string, title: string, reason: string|null, excerpt: string|null, featuredImage: string|null, favicon: string|null, url: string, oneClickSubscribe: boolean, createdAt?: Date, updatedAt?: Date|null}) {
+    constructor(data: {id?: string, title: string, reason: string|null, excerpt: string|null, featuredImage: string|null, favicon: string|null, url: URL, oneClickSubscribe: boolean, createdAt?: Date, updatedAt?: Date|null}) {
        this.id = data.id ?? ObjectId().toString();
        this.title = data.title;
        this.reason = data.reason;
--- a/ghost/recommendations/src/RecommendationController.ts
+++ b/ghost/recommendations/src/RecommendationController.ts
@ -38,6 +38,18 @@ function validateBoolean(object: any, key: string, {required = true} = {}): bool
    }
 }

+function validateURL(object: any, key: string, {required = true} = {}): URL|undefined {
+    const string = validateString(object, key, {required});
+    if (string !== undefined) {
+        try {
+            return new URL(string);
+        } catch (e) {
+            throw new errors.BadRequestError({message: `${key} must be a valid URL`});
+        }
+    }
+}
+
+
 export class RecommendationController {
    service: RecommendationService;

@ -67,7 +79,7 @@ export class RecommendationController {

        const cleanedRecommendation: Omit<Recommendation, 'id'|'createdAt'|'updatedAt'> = {
            title: validateString(recommendation, "title") ?? '',
-            url: validateString(recommendation, "url") ?? '',
+            url: validateURL(recommendation, "url")!,

            // Optional fields
            oneClickSubscribe: validateBoolean(recommendation, "one_click_subscribe", {required: false}) ?? false,
@ -89,7 +101,7 @@ export class RecommendationController {
        const recommendation = frame.data.recommendations[0];
        const cleanedRecommendation: Partial<Recommendation> = {
            title: validateString(recommendation, "title", {required: false}),
-            url: validateString(recommendation, "url", {required: false}),
+            url: validateURL(recommendation, "url", {required: false}),
            oneClickSubscribe: validateBoolean(recommendation, "one_click_subscribe", {required: false}),
            reason: validateString(recommendation, "reason", {required: false}),
            excerpt: validateString(recommendation, "excerpt", {required: false}),
@ -112,7 +124,7 @@ export class RecommendationController {
                    excerpt: r.excerpt,
                    featured_image: r.featuredImage,
                    favicon: r.favicon,
-                    url: r.url,
+                    url: r.url.toString(),
                    one_click_subscribe: r.oneClickSubscribe,
                    created_at: r.createdAt,
                    updated_at: r.updatedAt
--- a/ghost/recommendations/src/RecommendationService.ts
+++ b/ghost/recommendations/src/RecommendationService.ts
@ -1,26 +1,66 @@
 import {Recommendation} from "./Recommendation";
 import {RecommendationRepository} from "./RecommendationRepository";
+import {WellknownService} from "./WellknownService";
+
+type MentionSendingService = {
+    sendAll(options: {url: URL, links: URL[]}): Promise<void>
+}

 export class RecommendationService {
    repository: RecommendationRepository;
+    wellknownService: WellknownService;
+    mentionSendingService: MentionSendingService;

-    constructor(deps: {repository: RecommendationRepository}) {
+    constructor(deps: {repository: RecommendationRepository, wellknownService: WellknownService, mentionSendingService: MentionSendingService}) {
        this.repository = deps.repository;
+        this.wellknownService = deps.wellknownService;
+        this.mentionSendingService = deps.mentionSendingService;
+    }
+
+    async init() {
+        await this.updateWellknown();
+    }
+
+    async updateWellknown() {
+        const recommendations = await this.listRecommendations();
+        await this.wellknownService.set(recommendations);
+    }
+
+    sendMentionToRecommendation(recommendation: Recommendation) {
+         this.mentionSendingService.sendAll({
+            url: this.wellknownService.getURL(),
+            links: [
+                recommendation.url
+            ]
+        }).catch(console.error);
    }

    async addRecommendation(recommendation: Recommendation) {
-        return this.repository.add(recommendation);
+        const r = this.repository.add(recommendation);
+        await this.updateWellknown();
+
+        // Only send an update for the mentioned URL
+        this.sendMentionToRecommendation(recommendation);
+        return r;
    }

    async editRecommendation(id: string, recommendationEdit: Partial<Recommendation>) {
        // Check if it exists
        const existing = await this.repository.getById(id);
-        return this.repository.edit(existing.id, recommendationEdit);
+        const e = await this.repository.edit(existing.id, recommendationEdit);
+
+        await this.updateWellknown();
+        this.sendMentionToRecommendation(e);
+        return e;
    }

    async deleteRecommendation(id: string) {
        const existing = await this.repository.getById(id);
        await this.repository.remove(existing.id);
+        await this.updateWellknown();
+
+        // Send a mention (because it was deleted, according to the webmentions spec)
+        this.sendMentionToRecommendation(existing);
    }

    async listRecommendations() {
--- a/ghost/recommendations/src/WellknownService.ts
+++ b/ghost/recommendations/src/WellknownService.ts
@ -0,0 +1,48 @@
+import {Recommendation} from "./Recommendation"
+import fs from "fs/promises";
+import _path from 'path';
+
+type UrlUtils = {
+    relativeToAbsolute(url: string): string
+}
+type Options = {
+    /**
+     * Where to publish the wellknown file
+     */
+    dir: string,
+    urlUtils: UrlUtils
+}
+
+export class WellknownService {
+    dir: string
+    urlUtils: UrlUtils
+
+    constructor({dir, urlUtils}: Options) {
+        this.dir = dir;
+        this.urlUtils = urlUtils;
+    }
+
+    #formatRecommendation(recommendation: Recommendation) {
+        return {
+            url: recommendation.url,
+            reason: recommendation.reason,
+            updated_at: (recommendation.updatedAt ?? recommendation.createdAt).toISOString(),
+            created_at: (recommendation.createdAt).toISOString(),
+        }
+    }
+
+    getPath() {
+        return _path.join(this.dir, '/.well-known/recommendations.json');
+    }
+
+    getURL(): URL {
+        return new URL(this.urlUtils.relativeToAbsolute('/.well-known/recommendations.json'));
+    }
+
+    async set(recommendations: Recommendation[]) {
+        const content = JSON.stringify(recommendations.map(r => this.#formatRecommendation(r)));
+        const path = this.getPath();
+        await fs.mkdir(_path.dirname(path), {recursive: true});
+        await fs.writeFile(path, content);
+    }
+}
--- a/ghost/recommendations/src/index.ts
+++ b/ghost/recommendations/src/index.ts
@ -3,3 +3,4 @@ export * from './RecommendationService';
 export * from './RecommendationRepository';
 export * from './InMemoryRecommendationRepository';
 export * from './Recommendation';
+export * from './WellknownService';
--- a/ghost/webmentions/lib/Mention.js
+++ b/ghost/webmentions/lib/Mention.js
@ -21,11 +21,44 @@ module.exports = class Mention {

    /**
     * @param {string} html
+     * @param {string} contentType
     */
-    verify(html) {
-        const $ = cheerio.load(html);
-        const hasTargetUrl = $('a[href*="' + this.target.href + '"], img[src*="' + this.target.href + '"], video[src*="' + this.target.href + '"]').length > 0;
-        this.#verified = hasTargetUrl;
+    verify(html, contentType) {
+        const wasVerified = this.#verified;
+
+        if (contentType.includes('text/html')) {
+            try {
+                const $ = cheerio.load(html);
+                const hasTargetUrl = $('a[href*="' + this.target.href + '"], img[src*="' + this.target.href + '"], video[src*="' + this.target.href + '"]').length > 0;
+                this.#verified = hasTargetUrl;
+
+                if (wasVerified && !this.#verified) {
+                    // Delete the mention
+                    this.#deleted = true;
+                    this.#verified = true;
+                }
+            } catch (e) {
+                this.#verified = false;
+            }
+        }
+
+        if (contentType.includes('application/json')) {
+            try {
+                // Check valid JSON
+                JSON.parse(html);
+
+                // Check full text string is present in the json
+                this.#verified = !!html.includes(JSON.stringify(this.target.href));
+
+                if (wasVerified && !this.#verified) {
+                    // Delete the mention
+                    this.#deleted = true;
+                    this.#verified = true;
+                }
+            } catch (e) {
+                this.#verified = false;
+            }
+        }
    }

    /** @type {URL} */
@ -274,12 +307,19 @@ module.exports = class Mention {
        return mention;
    }

+    /**
+     * @returns {boolean}
+     */
+    isDeleted() {
+        return this.#deleted;
+    }
+
    /**
     * @param {Mention} mention
     * @returns {boolean}
     */
    static isDeleted(mention) {
-        return mention.#deleted;
+        return mention.isDeleted();
    }
 };

--- a/ghost/webmentions/lib/MentionSendingService.js
+++ b/ghost/webmentions/lib/MentionSendingService.js
@ -67,7 +67,7 @@ module.exports = class MentionSendingService {
            let previousHtml = post.previous('status') === 'published' ? post.previous('html') : null;
            if (html || previousHtml) {
                await this.#jobService.addJob('sendWebmentions', async () => {
-                    await this.sendAll({
+                    await this.sendForHTMLResource({
                        url: new URL(this.#getPostUrl(post)),
                        html: html,
                        previousHtml: previousHtml
@ -80,6 +80,10 @@ module.exports = class MentionSendingService {
        }
    }

+    /**
+     * @param {{source: URL, target: URL, endpoint: URL}} options
+     * @returns
+     */
    async send({source, target, endpoint}) {
        logging.info('[Webmention] Sending webmention from ' + source.href + ' to ' + target.href + ' via ' + endpoint.href);

@ -113,7 +117,7 @@ module.exports = class MentionSendingService {
     * @param {string} resource.html
     * @param {string|null} [resource.previousHtml]
     */
-    async sendAll(resource) {
+    async sendForHTMLResource(resource) {
        const links = resource.html ? this.getLinks(resource.html) : [];
        if (resource.previousHtml) {
            // We also need to send webmentions for removed links
@ -129,12 +133,25 @@ module.exports = class MentionSendingService {
            logging.info('[Webmention] Sending all webmentions for ' + resource.url.href);
        }

+        await this.sendAll({
+            url: resource.url,
+            links
+        });
+    }
+
+    /**
+     * Send a webmention call for the links in a resource.
+     * @param {object} resource
+     * @param {URL} resource.url
+     * @param {URL[]} resource.links
+     */
+    async sendAll({url, links}) {
        for (const target of links) {
            const endpoint = await this.#discoveryService.getEndpoint(target);
            if (endpoint) {
                // Send webmention call
                try {
-                    await this.send({source: resource.url, target, endpoint});
+                    await this.send({source: url, target, endpoint});
                } catch (e) {
                    logging.error('[Webmention] Failed sending via ' + endpoint.href + ': ' + e.message);
                }
--- a/ghost/webmentions/lib/MentionsAPI.js
+++ b/ghost/webmentions/lib/MentionsAPI.js
@ -68,13 +68,14 @@ const Mention = require('./Mention');

 /**
 * @typedef {object} WebmentionMetadata
- * @prop {string} siteTitle
- * @prop {string} title
- * @prop {string} excerpt
- * @prop {string} author
- * @prop {URL} image
- * @prop {URL} favicon
+ * @prop {string|null} siteTitle
+ * @prop {string|null} title
+ * @prop {string|null} excerpt
+ * @prop {string|null} author
+ * @prop {URL|null} image
+ * @prop {URL|null} favicon
 * @prop {string} body
+ * @prop {string|undefined} contentType
 */

 /**
@ -228,7 +229,7 @@ module.exports = class MentionsAPI {

        if (metadata?.body) {
            try {
-                mention.verify(metadata.body);
+                mention.verify(metadata.body, metadata.contentType);
            } catch (e) {
                logging.error(e);
            }
--- a/ghost/webmentions/test/Mention.test.js
+++ b/ghost/webmentions/test/Mention.test.js
@ -1,6 +1,8 @@
 const assert = require('assert/strict');
 const ObjectID = require('bson-objectid');
 const Mention = require('../lib/Mention');
+const cheerio = require('cheerio');
+const sinon = require('sinon');

 const validInput = {
    source: 'https://source.com',
@ -35,15 +37,40 @@ describe('Mention', function () {
    });

    describe('verify', function () {
+        afterEach(function () {
+            sinon.restore();
+        });
+
+        it('can handle invalid HTML', async function () {
+            const mention = await Mention.create(validInput);
+            assert(!mention.verified);
+
+            sinon.stub(cheerio, 'load').throws(new Error('Invalid HTML'));
+
+            mention.verify('irrelevant', 'text/html');
+            assert(!mention.verified);
+            assert(!mention.isDeleted());
+        });
+
        it('Does basic check for the target URL and updates verified property', async function () {
            const mention = await Mention.create(validInput);
            assert(!mention.verified);

-            mention.verify('<a href="https://target.com/">');
+            mention.verify('<a href="https://target.com/">', 'text/html');
            assert(mention.verified);
+            assert(!mention.isDeleted());

-            mention.verify('<a href="https://not-da-target.com">');
+            mention.verify('something else', 'text/html');
+            assert(mention.verified);
+            assert(mention.isDeleted());
+        });
+        it('detects differences', async function () {
+            const mention = await Mention.create(validInput);
            assert(!mention.verified);
+
+            mention.verify('<a href="https://not-target.com/">', 'text/html');
+            assert(!mention.verified);
+            assert(!mention.isDeleted());
        });
        it('Does check for Image targets', async function () {
            const mention = await Mention.create({
@ -52,11 +79,13 @@ describe('Mention', function () {
            });
            assert(!mention.verified);

-            mention.verify('<img src="https://target.com/image.jpg">');
+            mention.verify('<img src="https://target.com/image.jpg">', 'text/html');
            assert(mention.verified);
+            assert(!mention.isDeleted());

-            mention.verify('<img src="https://not-da-target.com/image.jpg">');
-            assert(!mention.verified);
+            mention.verify('something else', 'text/html');
+            assert(mention.verified);
+            assert(mention.isDeleted());
        });
        it('Does check for Video targets', async function () {
            const mention = await Mention.create({
@ -65,11 +94,35 @@ describe('Mention', function () {
            });
            assert(!mention.verified);

-            mention.verify('<video src="https://target.com/video.mp4">');
+            mention.verify('<video src="https://target.com/video.mp4">', 'text/html');
            assert(mention.verified);
+            assert(!mention.isDeleted());

-            mention.verify('<video src="https://not-da-target.com/video.mp4">');
+            mention.verify('something else', 'text/html');
+            assert(mention.verified);
+            assert(mention.isDeleted());
+        });
+
+        it('can verify links in JSON', async function () {
+            const mention = await Mention.create(validInput);
            assert(!mention.verified);
+
+            mention.verify('{"url": "https://target.com/"}', 'application/json');
+            assert(mention.verified);
+            assert(!mention.isDeleted());
+
+            mention.verify('{}', 'application/json');
+            assert(mention.verified);
+            assert(mention.isDeleted());
+        });
+
+        it('can handle invalid JSON', async function () {
+            const mention = await Mention.create(validInput);
+            assert(!mention.verified);
+
+            mention.verify('{"url": "ht', 'application/json');
+            assert(!mention.verified);
+            assert(!mention.isDeleted());
        });
    });

--- a/ghost/webmentions/test/MentionSendingService.test.js
+++ b/ghost/webmentions/test/MentionSendingService.test.js
@ -55,7 +55,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => false
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost({});
            sinon.assert.notCalled(stub);
        });
@ -64,7 +64,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => true
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            let options = {importing: true};
            await service.sendForPost({}, options);
            sinon.assert.notCalled(stub);
@ -74,7 +74,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => true
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            let options = {context: {internal: true}};
            await service.sendForPost({}, options);
            sinon.assert.notCalled(stub);
@ -84,7 +84,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => true
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'draft',
                html: 'changed',
@ -100,7 +100,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => true
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'published',
                html: 'same',
@ -116,7 +116,7 @@ describe('MentionSendingService', function () {
            const service = new MentionSendingService({
                isEnabled: () => true
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'send',
                html: 'changed',
@ -134,7 +134,7 @@ describe('MentionSendingService', function () {
                getPostUrl: () => 'https://site.com/post/',
                jobService: jobService
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'published',
                html: 'same',
@ -156,7 +156,7 @@ describe('MentionSendingService', function () {
                getPostUrl: () => 'https://site.com/post/',
                jobService: jobService
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'published',
                html: 'updated',
@ -177,7 +177,7 @@ describe('MentionSendingService', function () {
                isEnabled: () => true,
                getPostUrl: () => 'https://site.com/post/'
            });
-            sinon.stub(service, 'sendAll').rejects(new Error('Internal error test'));
+            sinon.stub(service, 'sendForHTMLResource').rejects(new Error('Internal error test'));
            await service.sendForPost(createModel({
                status: 'published',
                html: 'same',
@ -195,7 +195,7 @@ describe('MentionSendingService', function () {
                getPostUrl: () => 'https://site.com/post/',
                jobService: jobService
            });
-            const stub = sinon.stub(service, 'sendAll');
+            const stub = sinon.stub(service, 'sendForHTMLResource');
            await service.sendForPost(createModel({
                status: 'published',
                html: '',
@ -208,7 +208,7 @@ describe('MentionSendingService', function () {
        });
    });

-    describe('sendAll', function () {
+    describe('sendForHTMLResource', function () {
        it('Sends to all links', async function () {
            this.retries(1);
            let counter = 0;
@ -227,7 +227,7 @@ describe('MentionSendingService', function () {
                    getEndpoint: async () => new URL('https://example.org/webmentions-test')
                }
            });
-            await service.sendAll({url: new URL('https://site.com'),
+            await service.sendForHTMLResource({url: new URL('https://site.com'),
                html: `
                    <html>
                        <body>
@ -263,7 +263,7 @@ describe('MentionSendingService', function () {
                    getEndpoint: async () => new URL('https://example.org/webmentions-test')
                }
            });
-            await service.sendAll({url: new URL('https://site.com'),
+            await service.sendForHTMLResource({url: new URL('https://site.com'),
                html: `
                    <html>
                        <body>
@ -298,7 +298,7 @@ describe('MentionSendingService', function () {
                },
                jobService: jobService
            });
-            await service.sendAll({url: new URL('https://site.com'),
+            await service.sendForHTMLResource({url: new URL('https://site.com'),
                html: `<a href="https://example.com">Example</a>`,
                previousHtml: `<a href="https://typo.com">Example</a>`});
            assert.equal(scope.isDone(), true);
@ -311,7 +311,7 @@ describe('MentionSendingService', function () {
                isEnabled: () => true
            });
            const linksStub = sinon.stub(service, 'getLinks');
-            await service.sendAll({html: ``,previousHtml: ``});
+            await service.sendForHTMLResource({html: ``,previousHtml: ``});
            sinon.assert.notCalled(linksStub);
        });
    });
--- a/yarn.lock
+++ b/yarn.lock
@ -8588,7 +8588,7 @@
  dependencies:
    "@types/node" "*"

-"@types/node@*", "@types/node@>=10.0.0", "@types/node@>=12.12.47", "@types/node@>=13.7.0", "@types/node@>=8.1.0":
+"@types/node@*", "@types/node@>=10.0.0", "@types/node@>=12.12.47", "@types/node@>=13.7.0", "@types/node@>=8.1.0", "@types/node@^20.5.7":
  version "20.5.7"
  resolved "https://registry.yarnpkg.com/@types/node/-/node-20.5.7.tgz#4b8ecac87fbefbc92f431d09c30e176fc0a7c377"
  integrity sha512-dP7f3LdZIysZnmvP3ANJYTSwg+wLLl8p7RqniVlV7j+oXSXAbt9h0WIBFmJy5inWZoX9wZN6eXx+YXd9Rh3RBA==