Process tweets and sent to Discord

development.env.sample

@@ -3,3 +3,5 @@ SENTRY_ORG=
 SENTRY_PROJECT=
 SENTRY_DSN=
 TWITTER_BEARER_AUTH=
+TWITTER_USER_ID=
+DISCORD_WEBHOOK=

production.env.sample

@@ -3,3 +3,5 @@ SENTRY_ORG=
 SENTRY_PROJECT=
 SENTRY_DSN=
 TWITTER_BEARER_AUTH=
+TWITTER_USER_ID=
+DISCORD_WEBHOOK=

src/index.js

@@ -10,21 +10,102 @@ const textResponse = content => new Response(content, {
     },
 });
 
-// Util to send a JSON response
-const jsonResponse = obj => new Response(JSON.stringify(obj), {
-    headers: {
-        'Content-Type': 'application/json',
-    },
+// Util to suppress for Discord
+const suppressLinks = text => text.replace(/(https?:\/\/\S+)/g, '<$1>')
+
+// Util to escape Discord markdown in text
+const escapeMarkdown = text => suppressLinks(text)
+    .replace(/\\([*_`~\\])/g, '$1') // unescape already escaped chars
+    .replace(/([*_`~\\])/g, '\\$1'); // escape all MD chars
+
+// Util to add quote markdown to text
+const quoteText = text => `> ${text.split('\n').join('\n> ')}`;
+
+// Fetch latest Tweet data from Twitter
+const fetchLatestTweets = since => {
+    // Define the query params for the data we need
+    const req = new URL(`https://api.twitter.com/2/users/${process.env.TWITTER_USER_ID}/tweets`);
+    req.searchParams.set('max_results', '100');
+    req.searchParams.set('tweet.fields', ['referenced_tweets', 'text', 'created_at', 'id', 'author_id'].join(','));
+    req.searchParams.set('user.fields', ['username', 'profile_image_url'].join(','));
+    req.searchParams.set('expansions', ['author_id', 'referenced_tweets.id', 'referenced_tweets.id.author_id'].join(','));
+    if (since) req.searchParams.set('since_id', since);
+
+    // Make the request with the OAuth 2 token
+    return fetch(req.toString(), { headers: { Authorization: `Bearer ${process.env.TWITTER_BEARER_AUTH}` } })
+        .then(req => req.json());
+};
+
+// Post tweet information to Discord
+const postDiscordTweet = (type, content, links, username, avatar) => fetch(process.env.DISCORD_WEBHOOK, {
+    method: 'POST',
+    headers: { 'Content-type': 'application/json' },
+    body: JSON.stringify({
+        content: `**${type}**\n\n${quoteText(escapeMarkdown(content))}\n\n${suppressLinks(links)}`,
+        username,
+        avatar_url: avatar,
+    }),
 });
 
-const fetchRecentTweets = lastId => fetch(
-    `https://api.twitter.com/2/users/:id/tweets?limit=100${lastId ? `&since=${lastId}` : ''}`,
-    { headers: { Authorization: `Bearer ${process.env.TWITTER_BEARER_AUTH}` } },
-).then(req => req.json());
+// Process a raw Tweet from Discord and send it to Discord
+const processTweet = (tweet, includes) => {
+    // Resolve the author of the tweet
+    const author = includes.users.find(inclUser => inclUser.id === tweet.author_id);
+
+    // Resolve any referenced tweet
+    const refTweet = tweet.referenced_tweets && tweet.referenced_tweets.length
+        ? includes.tweets.find(inclTweet => inclTweet.id === tweet.referenced_tweets[0].id)
+        : null;
+    const refType = refTweet ? tweet.referenced_tweets[0].type : null;
+    const refAuthor = refTweet ? includes.users.find(inclUser => inclUser.id === refTweet.author_id) : null;
+
+    // Determine the Discord title
+    const title = refType === 'retweeted'
+        ? '🔁 Retweeted'
+        : refType === 'quoted'
+            ? '📝 Quoted'
+            : refType === 'replied_to'
+                ? '⤴️ Replied'
+                : '💬 Tweeted';
 
+    // Determine what content to use
+    const content = refType === 'retweeted' ? refTweet.text : tweet.text;
+
+    // Determine what links to reference
+    const links = refType === 'retweeted'
+        ? `https://twitter.com/${refAuthor.username}/status/${refTweet.id}`
+        : refType === 'quoted'
+            ? `https://twitter.com/${author.username}/status/${tweet.id}\nQuoting https://twitter.com/${refAuthor.username}/status/${refTweet.id}`
+            : refType === 'replied_to'
+                ? `https://twitter.com/${author.username}/status/${tweet.id}\nReplying to https://twitter.com/${refAuthor.username}/status/${refTweet.id}`
+                : `https://twitter.com/${author.username}/status/${tweet.id}`;
+
+    // Post to Discord
+    return postDiscordTweet(title, content, links, author.username, author.profile_image_url);
+};
+
+// Mirror latest tweets from Twitter to Discord
 const mirrorLatestTweets = async () => {
-    const data = await fetchRecentTweets();
-    console.log(data);
+    // Get the last tweet we processed
+    const last = await TWEETS_TO_DISCORD_LAST_TWEET.get('latest_id');
+
+    // Get new tweets since last processed (oldest first)
+    const data = await fetchLatestTweets(last);
+    const tweets = data.data ? data.data.sort((a, b) => new Date(a.created_at) - new Date(b.created_at)) : [];
+
+    // If we haven't run before, store the most recent tweet and abort
+    if (!last && tweets.length) {
+        await TWEETS_TO_DISCORD_LAST_TWEET.put('latest_id', tweets[tweets.length - 1].id);
+        return;
+    }
+
+    // Process each tweet
+    for (const tweet of tweets) {
+        console.log(await processTweet(tweet, data.includes).then(res => res.text()));
+
+        // Store this as the most recent tweet we've processed
+        await TWEETS_TO_DISCORD_LAST_TWEET.put('latest_id', tweet.id);
+    }
 };
 
 // Process all requests to the worker
@@ -37,8 +118,13 @@ const handleRequest = async ({ request, wait, sentry }) => {
     // Execute triggers route
     if (url.pathname === '/execute') {
         // Trigger each workflow in the background after
-        wait(mirrorLatestTweets().catch(err => sentry.captureException(err)));
-        return jsonResponse({});
+        wait(mirrorLatestTweets().catch(err => {
+            // Log & re-throw any errors
+            console.error(err);
+            sentry.captureException(err);
+            throw err;
+        }));
+        return textResponse('Executed');
     }
 
     // Not found

wrangler.toml

@@ -4,13 +4,13 @@ account_id = "fb1f542488f2441acf88ca15f3a8390d"
 workers_dev = true
 webpack_config = "webpack.config.js"
 kv_namespaces = [
-    { binding = "TWEETS_TO_DISCORD_LAST_TWEET", id = "4fc9f04e2f29425c878cf74200359002", preview_id = "4fc9f04e2f29425c878cf74200359002" }
+    { binding = "TWEETS_TO_DISCORD_LAST_TWEET", id = "f22f1aee1f3642bcaa81eaf306528577", preview_id = "f22f1aee1f3642bcaa81eaf306528577" }
 ]
 
 [triggers]
-crons = ["* * * * *"]
+crons = ["*/2 * * * *"]
 
 [env.production]
 kv_namespaces = [
-    { binding = "TWEETS_TO_DISCORD_LAST_TWEET", id = "e8a41596dbff45ab84f7833da8834bbb" }
+    { binding = "TWEETS_TO_DISCORD_LAST_TWEET", id = "87d5c2be0d2342f680bec6a0b20a372d" }
 ]