rubberguppe/routes/api.js

'use strict';
const express = require('express'),
      router = express.Router(),
      request = require('request'),
      crypto = require('crypto');

router.post('/sendMessage', function (req, res) {
  let db = req.app.get('db');
  console.log('DB',db);
  let domain = req.app.get('domain');
  let acct = req.body.acct;
  let apikey = req.body.apikey;
  let message = req.body.message;
  // check to see if your API key matches
  db.get('select apikey from accounts where name = $name', {$name: `${acct}@${domain}`}, (err, result) => {
    if (result.apikey === apikey) {
      sendCreateMessage(message, acct, domain, req, res);
    }
    else {
      res.status(403).json({msg: 'wrong api key'});
    }
  });
});

function signAndSend(message, name, domain, req, res, targetDomain, inbox) {
  // get the private key
  let db = req.app.get('db');
  let inboxFragment = inbox.replace('https://'+targetDomain,'');
  db.get('select privkey from accounts where name = $name', {$name: `${name}@${domain}`}, (err, result) => {
    if (result === undefined) {
      console.log(`No record found for ${name}.`);
    }
    else {
      let privkey = result.privkey;
      const signer = crypto.createSign('sha256');
      let d = new Date();
      let stringToSign = `(request-target): post ${inboxFragment}\nhost: ${targetDomain}\ndate: ${d.toUTCString()}`;
      signer.update(stringToSign);
      signer.end();
      const signature = signer.sign(privkey);
      const signature_b64 = signature.toString('base64');
      let header = `keyId="https://${domain}/u/${name}",headers="(request-target) host date",signature="${signature_b64}"`;
      request({
        url: inbox,
        headers: {
          'Host': targetDomain,
          'Date': d.toUTCString(),
          'Signature': header
        },
        method: 'POST',
        json: true,
        body: message
      }, function (error, response){
        console.log(`Sent message to an inbox at ${targetDomain}!`);
        if (error) {
          console.log('Error:', error, response);
        }
        else {
          console.log('Response Status Code:', response.statusCode);
        }
      });
    }
  });
}

function createMessage(text, name, domain, req, res) {
  const guidCreate = crypto.randomBytes(16).toString('hex');
  const guidNote = crypto.randomBytes(16).toString('hex');
  let db = req.app.get('db');
  let d = new Date();

  let noteMessage = {
    'id': `https://${domain}/m/${guidNote}`,
    'type': 'Note',
    'published': d.toISOString(),
    'attributedTo': `https://${domain}/u/${name}`,
    'content': text,
    'to': 'https://www.w3.org/ns/activitystreams#Public'
  };

  let createMessage = {
    '@context': 'https://www.w3.org/ns/activitystreams',

    'id': `https://${domain}/m/${guidCreate}`,
    'type': 'Create',
    'actor': `https://${domain}/u/${name}`,

    'object': noteMessage
  };

  db.run('insert or replace into messages(guid, message) values($guid, $message)', {
    $guid: guidCreate,
    $message: JSON.stringify(createMessage),
  }, (err, accounts) => {
  });
  db.run('insert or replace into messages(guid, message) values($guid, $message)', {
    $guid: guidNote,
    $message: JSON.stringify(noteMessage),
  }, (err, accounts) => {
  });

  return createMessage;
}

function sendCreateMessage(text, name, domain, req, res) {
  let message = createMessage(text, name, domain, req, res);
  let db = req.app.get('db');

  db.get('select followers from accounts where name = $name', {$name: `${name}@${domain}`}, (err, result) => {
    let followers = JSON.parse(result.followers);
    console.log(followers);
    console.log('type',typeof followers);
    if (followers === null) {
      console.log('aaaa');
      res.status(400).json({msg: `No followers for account ${name}@${domain}`});
    }
    else {
      for (let follower of followers) {
        let inbox = follower+'/inbox';
        let myURL = new URL(follower);
        let targetDomain = myURL.hostname;
        signAndSend(message, name, domain, req, res, targetDomain, inbox);
      }
      res.status(200).json({msg: 'ok'});
    }
  });
}

module.exports = router;