function jsonMsgSuffix(jsonString) {
  if (jsonString === undefined) {
    return "";
  }
  try {
    const fingerprint = JSON.parse(jsonString);
    return `\`\`\`# Unlocked by\n${JSON.stringify(fingerprint, null, 4)}\`\`\``;
  } catch (e) {
    return `\`\`\`# Unlocked by\n# WARN: Unknown or corrupt raw fingerprint:\n ${jsonString}\`\`\``;
  }
}

exports.handler = async function(context, event, callback) {
  const response = new Twilio.Response();
  const discordPath = Runtime.getFunctions()['common/discord'].path;
  const discord = require(discordPath);

  let users = event.discordUser;
  let msgs = event.msg;
  let jsons = event.json;
  let promises;

  try {
    users = JSON.parse(users);
    msgs = JSON.parse(msgs);
    jsons = JSON.parse(jsons);

    promises = msgs.map((msg, i) => 
      discord.sendMessageToUser(
        context,
        users[i], 
        msg + jsonMsgSuffix(jsons[i])
      ).catch(e => console.error(e))
    );
  } catch (e) {
    console.error(e);
  }

  setTimeout(() => {
    console.log("Ungraceful finish: running out of time");
    callback(null, response);
  }, 5000);

  await Promise.all(promises);
  return callback(null, response);
};