ghmatch.js

const request = require('request-promise-native');
const Set = require('immutable').Set;
const parseLinkHeader = require('parse-link-header');

const fetchRepos = uri =>
  request({
    uri,
    json: true,
    resolveWithFullResponse: true,
    headers: { 'User-Agent': 'ghmatch' },
  })
    .then(({ headers, body: repos }) => ({
      repos,
      links: parseLinkHeader(headers['link']),
    }))
    .then(
      ({ links, repos }) =>
        links.next
          ? fetchRepos(links.next.url).then(nextRepos =>
            repos.concat(nextRepos)
          )
          : repos
    );

const fetchStarredRepos = username =>
  fetchRepos(`https://api.github.com/users/${username}/starred`);

const reposToSetOfFullNames = repos =>
  Set(repos.map(repo => repo['full_name']));

const getMatchingRepos = (user1, user2) =>
  Promise.all([fetchStarredRepos(user1), fetchStarredRepos(user2)])
    .then(results => results.map(reposToSetOfFullNames))
    .then(([repos1, repos2]) => repos1.intersect(repos2));

getMatchingRepos('bfncs', 'derveloper').then(console.log).catch(console.error);