Gets group information (name, id, description, url, logo url) from Facebook Graph API.

get-user-group-info.js

const http = require('got');
const coroutine = require('co');
const querystring = require('querystring');

const ACCESS_TOKEN = '<ACCESS_TOKEN>';

const groupNamesOrIds = [
  'JavaScript Dominicana',
  1398701893767285, // Ruby.do
  'hfsantodomingo',
  'mobilenetSDQ',
  'cddvorg',
  'uiuxdominicana',
  'csharp.do',
  'devdominicanos',
  'cocos2dx.do'
];

const getGroupsIdPromise = groupNamesOrIds.map(n => {
  if (isNumber(n)) {
    return Promise.resolve(n);
  }

  return getGroupIdByName(n);
});

function getGroupIdByName(name) {
  const url = getGraphApiUrlFor({
    endpoint: 'search', query: {q: name, type: 'group'}
  });

  return getAsJson(url)
  .catch(e => console.log(e))
  .then(response => {
    return response;
  })
  .then(response => response.body.data[0].id)
  .then(id => Number(id));
}

function getGraphApiUrlFor(options) {
  const path = options.path;
  const query = options.query;
  const endpoint = options.endpoint;
  const accessToken = options.accessToken || ACCESS_TOKEN;

  const baseGraphApiUrl = 'https://graph.facebook.com/v2.5';
  const queryString = querystring.stringify(query);

  const url = `${baseGraphApiUrl}` + (endpoint ? `/${endpoint}` : '') + (path ? `/${path}` : '') + `/?access_token=${accessToken}` + (query ? `&${queryString}` : '');

  return url;
}

/* main */
coroutine(function* () {
  const groupIds = yield getGroupsIdPromise;

  const groups = yield groupIds.map(getGroupInfoById);

  console.log(JSON.stringify(groups, null, 2));
})
.catch(e => {
  console.error(e.stack);
});
/* end main */

function getGroupInfoById(id) {
  const url = getGraphApiUrlFor({
    path: id,
    query: {
      fields: 'id,name,icon,description'
    }
  });

  return getAsJson(url)
  .then(response => response.body)
  .then(groupInfo => {
    groupInfo.facebookUrl = `https://www.facebook.com/groups/${id}`;

    return groupInfo;
  })
  .then(groupInfo => {
    return Promise.all([
      groupInfo,
      getGroupCreationDateById(id)
    ]);
  })
  .then(promises => {
    const groupInfo = promises[0];
    const creationDate = promises[1];

    return Object.assign({}, groupInfo, {creationDate});
  });
}

function getGroupCreationDateById(id) {
  return getGroupEventsById(id)
  .then(response => response.data)
  .then(events => events.map(e => new Date(e.start_time)))
  .then(eventDates => eventDates.map(e => e.getTime()))
  .then(
    eventTimes => eventTimes.sort((a, b) => {
      return a - b;
    })
  )
  .then(eventTimes => eventTimes[0]);
}

function getGroupEventsById(id) {
  const url = getGraphApiUrlFor({
    path: 'events',
    endpoint: id
  });

  return getAsJson(url).then(response => response.body);
}

function getAsJson(url) {
  const options = {
    json: true
  };

  return http.get(url, options);
}

/* Helpers */

function isNumber(n) {
  return typeof n === 'number';
}