Initial wire up of Posts -> Outbox flow

ref https://linear.app/tryghost/issue/MOM-29

This is very rough, and all still behind a flag. The idea is that any public
post which is published gets added to the Outbox of the site Actor. We also
dispatch an event, which will be used to deliver the Activity to any relevant
inboxes, but that is outside the scope of this commit.

ghost/core/core/boot.js

@@ -408,6 +408,12 @@ async function initNestDependencies() {
     }, {
         provide: 'SettingsCache',
         useValue: require('./shared/settings-cache')
+    }, {
+        provide: 'knex',
+        useValue: require('./server/data/db').knex
+    }, {
+        provide: 'UrlUtils',
+        useValue: require('./shared/url-utils')
     });
     for (const provider of providers) {
         GhostNestApp.addProvider(provider);

ghost/ghost/src/core/activitypub/activity.service.ts

@@ -0,0 +1,36 @@
+import ObjectID from 'bson-objectid';
+import {ActorRepository} from './actor.repository';
+import {Article} from './article.object';
+import {PostRepository} from './post.repository';
+import {Inject} from '@nestjs/common';
+
+export class ActivityService {
+    constructor(
+        @Inject('ActorRepository') private readonly actorRepository: ActorRepository,
+        @Inject('PostRepository') private readonly postRepository: PostRepository
+    ) {}
+
+    async createArticleForPost(postId: ObjectID) {
+        const actor = await this.actorRepository.getOne('index');
+
+        if (!actor) {
+            throw new Error('Actor not found');
+        }
+
+        const post = await this.postRepository.getOne(postId);
+
+        if (!post) {
+            throw new Error('Post not found');
+        }
+
+        if (post.visibility !== 'public') {
+            return;
+        }
+
+        const article = Article.fromPost(post);
+
+        actor.createArticle(article);
+
+        await this.actorRepository.save(actor);
+    }
+}

ghost/ghost/src/core/activitypub/article.object.ts

@@ -1,5 +1,6 @@
 import ObjectID from 'bson-objectid';
 import {ActivityPub} from './types';
+import {Post} from './post.repository';
 
 type ArticleData = {
     id: ObjectID
@@ -8,15 +9,6 @@ type ArticleData = {
     url: URL
 };
 
-type Post = {
-    id: ObjectID;
-    title: string;
-    slug: string;
-    html: string;
-    lexical: string;
-    status: 'draft' | 'published' | 'scheduled' | 'sent';
-};
-
 export class Article {
     constructor(private readonly attr: ArticleData) {}
 

ghost/ghost/src/core/activitypub/jsonld.service.ts

@@ -1,10 +1,13 @@
 import {Inject} from '@nestjs/common';
 import {ActorRepository} from './actor.repository';
 import ObjectID from 'bson-objectid';
+import {PostRepository} from './post.repository';
+import {Article} from './article.object';
 
 export class JSONLDService {
     constructor(
         @Inject('ActorRepository') private repository: ActorRepository,
+        @Inject('PostRepository') private postRepository: PostRepository,
         @Inject('ActivityPubBaseURL') private url: URL
     ) {}
 
@@ -28,4 +31,15 @@ export class JSONLDService {
             orderedItems: actor.outbox.map(activity => activity.getJSONLD(this.url))
         };
     }
+
+    async getArticle(id: ObjectID) {
+        const post = await this.postRepository.getOne(id);
+        if (!post) {
+            throw new Error('Not found');
+        }
+        if (post.visibility !== 'public') {
+            throw new Error('Cannot view');
+        }
+        return Article.fromPost(post).getJSONLD(this.url);
+    }
 }

ghost/ghost/src/core/activitypub/post.repository.ts

@@ -0,0 +1,13 @@
+import ObjectID from 'bson-objectid';
+
+export type Post = {
+    id: ObjectID;
+    title: string;
+    slug: string;
+    html: string;
+    visibility: string;
+};
+
+export interface PostRepository {
+    getOne(id: ObjectID): Promise<Post | null>
+}

ghost/ghost/src/db/in-memory/actor.repository.in-memory.ts

@@ -3,7 +3,6 @@ import {ActorRepository} from '../../core/activitypub/actor.repository';
 import ObjectID from 'bson-objectid';
 import {Inject} from '@nestjs/common';
 import {SettingsCache} from '../../common/types/settings-cache.type';
-import {Activity} from '../../core/activitypub/activity.object';
 
 interface DomainEvents {
     dispatch(event: unknown): void

ghost/ghost/src/db/knex/post.repository.knex.ts

@@ -0,0 +1,32 @@
+import {Inject} from '@nestjs/common';
+import ObjectID from 'bson-objectid';
+import {PostRepository} from '../../core/activitypub/post.repository';
+
+type UrlUtils = {
+    transformReadyToAbsolute(html: string): string
+}
+
+export class KnexPostRepository implements PostRepository {
+    constructor(
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        @Inject('knex') private readonly knex: any,
+        @Inject('UrlUtils') private readonly urlUtils: UrlUtils
+    ) {}
+    async getOne(identifier: ObjectID) {
+        return this.getOneById(identifier);
+    }
+
+    async getOneById(id: ObjectID) {
+        const row = await this.knex('posts').where('id', id.toHexString()).first();
+        if (!row) {
+            return null;
+        }
+        return {
+            id,
+            title: row.title,
+            html: this.urlUtils.transformReadyToAbsolute(row.html),
+            slug: row.slug,
+            visibility: row.visibility
+        };
+    }
+};

ghost/ghost/src/http/frontend/controllers/activitypub.controller.ts

@@ -30,4 +30,15 @@ export class ActivityPubController {
         }
         return this.service.getOutbox(ObjectID.createFromHexString(owner));
     }
+
+    @Header('Cache-Control', 'no-store')
+    @Header('Content-Type', 'application/activity+json')
+    @Roles(['Anon'])
+    @Get('article/:id')
+    async getArticle(@Param('id') id: unknown) {
+        if (typeof id !== 'string') {
+            throw new Error('Bad Request');
+        }
+        return this.service.getArticle(ObjectID.createFromHexString(id));
+    }
 }

ghost/ghost/src/nestjs/modules/activitypub.module.ts

@@ -4,6 +4,8 @@ import {ActivityPubController} from '../../http/frontend/controllers/activitypub
 import {WebFingerService} from '../../core/activitypub/webfinger.service';
 import {JSONLDService} from '../../core/activitypub/jsonld.service';
 import {WebFingerController} from '../../http/frontend/controllers/webfinger.controller';
+import {ActivityService} from '../../core/activitypub/activity.service';
+import {KnexPostRepository} from '../../db/knex/post.repository.knex';
 
 @Module({
     controllers: [ActivityPubController, WebFingerController],
@@ -13,6 +15,14 @@ import {WebFingerController} from '../../http/frontend/controllers/webfinger.con
             provide: 'ActorRepository',
             useClass: ActorRepositoryInMemory
         },
+        {
+            provide: 'ActivityService',
+            useClass: ActivityService
+        },
+        {
+            provide: 'PostRepository',
+            useClass: KnexPostRepository
+        },
         WebFingerService,
         JSONLDService
     ]

ghost/posts-service/lib/PostsService.js

@@ -12,6 +12,8 @@ const {
     PostsBulkUnfeaturedEvent,
     PostsBulkAddTagsEvent
 } = require('@tryghost/post-events');
+const GhostNestApp = require('@tryghost/ghost');
+const {default: ObjectID} = require('bson-objectid');
 
 const messages = {
     invalidVisibilityFilter: 'Invalid visibility filter.',
@@ -207,6 +209,13 @@ class PostsService {
             }
         }
 
+        if (this.isSet('ActivityPub')) {
+            if (model.previous('status') !== model.get('status') && model.get('status') === 'published') {
+                const activityService = await GhostNestApp.resolve('ActivityService');
+                await activityService.createArticleForPost(ObjectID.createFromHexString(model.id));
+            }
+        }
+
         if (typeof options?.eventHandler === 'function') {
             await options.eventHandler(this.getChanges(model), dto);
         }