Added primitive thumbnailer.

src/cli.js

@@ -1,7 +1,8 @@
 // import config from 'config';
 import yargs from 'yargs';
+import { hideBin } from 'yargs/helpers';
 
-const { argv } = yargs
+const { argv } = yargs(hideBin(process.argv))
 	.command('npm start')
 	.option('log-level', {
 		alias: 'level',

src/posts.js

@@ -5,8 +5,13 @@ import { HttpError } from './errors';
 
 import { fetchShelf, fetchShelves } from './shelves';
 import { fetchUsers } from './users';
+import { generateThumbnail } from './thumbnails';
 import slugify from './utils/slugify';
 
+import initLogger from './logger';
+
+const logger = initLogger();
+
 const emptyVote = {
 	tally: 0,
 	total: 0,
@@ -25,6 +30,7 @@ function curateDatabasePost(post, {
 		link: post.link,
 		shelfId: post.shelf_id,
 		createdAt: post.created_at,
+		hasThumbnail: post.thumbnail,
 		shelf: shelf || shelves?.[post.shelf_id],
 		user: users.find((user) => user.id === post.user_id),
 		vote: vote || votes?.[post.id] || emptyVote,
@@ -166,6 +172,8 @@ async function votePost(postId, value, user) {
 			.merge();
 	}
 
+	logger.silly(`User ${user.username} voted ${value} on post ${postId}`);
+
 	const votes = await fetchPostVotes([postId], user);
 
 	return votes[postId] || emptyVote;
@@ -198,6 +206,10 @@ async function createPost(post, shelfId, user) {
 		votePost(postEntry.id, 1, user),
 	]);
 
+	logger.verbose(`User ${user.username} created post ${postEntry.id} on s/${shelf.slug}`);
+
+	generateThumbnail(postEntry.id);
+
 	return curateDatabasePost(postEntry, { shelf, users, vote });
 }
 

src/thumbnails.js

@@ -0,0 +1,80 @@
+import bhttp from 'bhttp';
+import unprint from 'unprint';
+import fs from 'fs';
+import sharp from 'sharp';
+
+import knex from './knex';
+import initLogger from './logger';
+
+const logger = initLogger();
+
+async function createThumbnail(data, post) {
+	await fs.promises.mkdir('media/thumbnails', { recursive: true });
+
+	await sharp(data)
+		.resize(300, 300)
+		.jpeg({
+			quality: 80,
+		})
+		.toFile(`media/thumbnails/${post.id}.jpeg`);
+
+	await knex('posts')
+		.where('id', post.id)
+		.update('thumbnail', true);
+
+	logger.debug(`Saved thumbnail for ${post.id}`);
+}
+
+async function generateThumbnail(postId) {
+	const post = await knex('posts').where('id', postId).first();
+
+	if (!post) {
+		logger.warn(`Cannot generate thumbnail for non-existent post ${postId}`);
+		return;
+	}
+
+	if (!post.link) {
+		logger.debug(`Skipped thumbnail generation for text-only post ${postId}`);
+		return;
+	}
+
+	const res = await bhttp.get(post.link);
+
+	if (res.statusCode !== 200) {
+		logger.warn(`Failed thumbnail generation for ${post.link} from ${postId} (${res.statusCode})`);
+		return;
+	}
+
+	if (res.headers['content-type'].includes('image/')) {
+		await createThumbnail(res.body, post);
+		return;
+	}
+
+	const { query } = unprint.init(res.body.toString());
+	const ogHeader = query.attribute('meta[property="og:image"]', 'content');
+
+	if (ogHeader) {
+		const imgRes = await bhttp.get(ogHeader);
+
+		if (imgRes.statusCode === 200 && imgRes.headers['content-type'].includes('image/')) {
+			await createThumbnail(imgRes.body, post);
+		}
+	}
+}
+
+async function generateMissingThumbnails(force = false) {
+	const postsWithoutThumbnail = await knex('posts')
+		.select('id')
+		.modify((builder) => {
+			if (!force) {
+				builder.where('thumbnail', false);
+			}
+		});
+
+	await Promise.all(postsWithoutThumbnail.map(async (post) => generateThumbnail(post.id)));
+}
+
+export {
+	generateThumbnail,
+	generateMissingThumbnails,
+};

src/tools/generate-thumbs.js

@@ -0,0 +1,9 @@
+import { generateMissingThumbnails } from '../thumbnails';
+import args from '../cli';
+
+async function init() {
+	await generateMissingThumbnails(!!args.force);
+	process.exit();
+}
+
+init();