const Twitter = require('twit') const morph = require('morphmorph') const RATE_LIMIT_CODE = 420 const MAX_ALT_TEXT_LENGTH = 420 let client try { client = new Twitter({ consumer_key: process.env.TWITTER_CONSUMER_KEY, consumer_secret: process.env.TWITTER_CONSUMER_SECRET, access_token: process.env.TWITTER_ACCESS_TOKEN_KEY, access_token_secret: process.env.TWITTER_ACCESS_TOKEN_SECRET }) } catch (e) { // eslint-disable-next-line console.warn(e.message); } const extractMediaId = morph.get('data.media_id_string') const extractImageUrl = morph.get('data.entities.media.0.display_url') const extractErrorCode = morph.get('0.code') const uploadImage = data => client.post('media/upload', { media_data: data }) const uploadMetadata = (altText, twitterRes = {}) => { if (!altText) return twitterRes const formattedAltText = altText.length > MAX_ALT_TEXT_LENGTH ? `${altText.slice(0, MAX_ALT_TEXT_LENGTH - 3)}...` : altText return client .post('media/metadata/create', { media_id: extractMediaId(twitterRes), alt_text: { text: formattedAltText } }) .then(() => twitterRes) } const uploadTweet = (twitterRes = {}) => client.post('statuses/update', { status: `Carbon Copy #${extractMediaId(twitterRes).slice(0, 8)}`, media_ids: extractMediaId(twitterRes) }) const respondSuccess = (res, url) => res.json({ url }) const respondFail = (res, err) => { const errorCode = extractErrorCode(err) // check for rate limit if (errorCode === RATE_LIMIT_CODE) { return res.status(420).send() } // eslint-disable-next-line console.error(`Error: ${err.message || JSON.stringify(err, null, 2)}`) return res.status(500).send() } module.exports = (req, res) => { if (!req.body.imageData) { return res.status(400).send() } return uploadImage(req.body.imageData) .then(uploadMetadata.bind(null, req.body.altText)) .then(uploadTweet) .then(extractImageUrl) .then(respondSuccess.bind(null, res)) .catch(respondFail.bind(null, res)) }