Embed Twitter video

Note: the process described here no longer works due to new restrictions in Twitter’s API.

Last night, I spent some time exploring Twitter’s documentation for embedding tweets. I needed to embed a tweet with an attached video, play the video programmatically, and detect when the video finishes. Twitter has no such API to observe playback state… but HTML5 video does! Here is my workaround, which hopefully saves you some time:

Load Twitter’s embed widget using the tweet’s ID
On a server (AWS Lambda in my case) use the Twitter API to lookup the tweet’s metadata
Grab the .mp4 video URLs from the JSON response
Replace the tweet widget’s media content with a <video> tag referencing the .mp4 URL

My full source code is reproduced below:

const https = require("https");
const { TWITTER_CONSUMER_API_KEY, TWITTER_CONSUMER_API_SECRET_KEY } = process.env;

const mediaUrl = id => {
  return "https://api.twitter.com/1.1/statuses/show.json?include_entities=true&id=" + id;
};

const request = (url, options) => {
  return new Promise((resolve) => {
    https
      .request(url, options, response => {
        let body = "";
        response.on("data", x => body += x);
        response.on("end", () => resolve({ statusCode: response.statusCode, body: body }));
      })
      .end(options.body);
  });
};

exports.handler = (event, _, callback) => {
  const credentials =
    encodeURIComponent(TWITTER_CONSUMER_API_KEY)
    + ":"
    + encodeURIComponent(TWITTER_CONSUMER_API_SECRET_KEY);
  request("https://api.twitter.com/oauth2/token", {
    method: "POST",
    body: "grant_type=client_credentials",
    headers: {
      "Content-Type": "application/x-www-form-urlencoded;charset=UTF-8",
      "Authorization": "Basic " + Buffer.from(credentials).toString("base64"),
    },
  }).then(response => {
    console.info(response);
    return request(mediaUrl(event.queryStringParameters.tweet), {
      method: "GET",
      headers: {
        Authorization: "Bearer " + JSON.parse(response.body).access_token,
      }
    });
  }).then(response => {
    console.info(response);
    const [ { url } ] = JSON.parse(response.body).extended_entities.media
      .map(x => x.video_info.variants)
      .reduce((acc, x) => acc.concat(x), [])
      .filter(x => x.content_type === "video/mp4")
      .sort((a, b) => b.bitrate - a.bitrate);
    callback(null, {
      statusCode: 200,
      body: url,
      headers: {
        "Access-Control-Allow-Origin": "*",
        "Access-Control-Allow-Headers": "content-type",
      },
    });
  }).catch(err => {
    console.error(err, event);
    callback(null, { statusCode: 500, body: "" });
  });
};