var gaExtractor = require('ga-extractor');

var options = {
  clientEmail: "[email protected]",
  // need either keyPath or keyContent
  keyPath: "test/fixtures/xxx.p12",
  keyContent: "Bag Attributes...",
  // below are optional
  profileId: "xxxxxxxx", // define once here or define a different one in every queryObj
  impersonatedUser: "[email protected]"
  proxy: "http://proxy.example.com"
};

var gaExtractor = new GaExtractor(options);

// To build your query, see
// https://developers.google.com/analytics/devguides/reporting/core/v3/reference#q_summary
// and https://developers.google.com/analytics/devguides/reporting/core/v3/reference
var queryObj = {
  'start-date': '31daysAgo',
  'end-date': 'yesterday',
  'metrics': 'ga:users',
  'dimensions': 'ga:country'
  // no need to define 'max-results', always extracts all data
};

gaExtractor.extract(queryObj)
  .then(function (data) {
    // do something with data returned, e.g. transform & load into database
    data = [
      ["United States", "5471"],
      ["United Kingdom", "1084"],
      ["France", "801"]
      // ...
    ];
  })
  .catch(console.error);