gistfile1.js

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */


// TODO: it would be nice to check size of places DB before starting (precondition?)
// TODO: do we need to listen for shutdown events to avoid corrupting the DB?
//       or does PlacesUtils handle that for us?

const {classes: Cc, interfaces: Ci, utils: Cu} = Components;
Cu.import("resource://gre/modules/PlacesUtils.jsm");
Cu.import("resource://gre/modules/Promise.jsm");

var serpCountQuery = 'SELECT COUNT(*) AS count FROM moz_historyvisits ' +
                     'INNER JOIN moz_places ' +
                     'ON moz_historyvisits.place_id = moz_places.id ' +
                     'WHERE moz_places.url LIKE ":providerURL" ;';
var counts = {
  google: null,
  yahoo: null,
  amazon: null,
  total: null
};

var getCount = function(url, db) {
  try {
    var query = serpCountQuery.replace(':providerURL', url);
    return db.execute(query);
  } catch (ex) {
    return Promise.reject(ex);
  }
};
var getGoogleCount = getCount.bind(null, '%google.com/search?q%');
var getYahooCount = getCount.bind(null, '%/search.yahoo.com/yhs/search?p%');
var getBingCount = getCount.bind(null, '%bing.com/search?q%');
var getAmazonCount = getCount.bind(null, '%amazon.com/s?%');

var saveCount = function(providerName, results) {
  var count = results && results[0] && results[0].getResultByName('count');
  counts[providerName] = count;
  console.log('the ' + providerName + ' count is ' + count);
  return Promise.resolve(count);
};

var totalCount = function(db) {
  try {
    var query = 'SELECT COUNT(*) AS count FROM moz_historyvisits;';
    return db.execute(query);
  } catch (ex) {
    return Promise.reject(ex);
  }
};
var summarize = function() {
  // round to two decimal places
  function _round(n) {
    return parseFloat(n.toPrecision(3));
  }

  // convert absolute counts into percentages (eg 5.18%),
  // and round off the total number of visits to the nearest thousand
  //
  // XXX: not guarding against division by zero; might see some NaNs or Infinitys.
  var result = {
    total: Math.round(counts.total / 1000) * 1000,
    google: _round(counts.google / counts.total),
    yahoo: _round(counts.yahoo / counts.total),
    bing: _round(counts.bing / counts.total),
    amazon: _round(counts.amazon/ counts.total)
  };

  return Promise.resolve(result);
}

var send = function(data) {
  // JSONify the data, if necessary (does telemetry do this?)
  // ship down using telemetry libs
};

var onError = function(err) {
  // TODO: what's the right way to handle errors here?
  console.log(err);
}

PlacesUtils.promiseDBConnection()
  .then(getGoogleCount, onError)
  .then(saveCount.bind(null, 'google'), onError)
  .then(PlacesUtils.promiseDBConnection, onError)
    .then(getYahooCount, onError)
    .then(saveCount.bind(null, 'yahoo'), onError)
  .then(PlacesUtils.promiseDBConnection, onError)
    .then(getAmazonCount, onError)
    .then(saveCount.bind(null, 'amazon'), onError)
  .then(PlacesUtils.promiseDBConnection, onError)
    .then(getTotalCount, onError)
    .then(saveCount.bind(null, 'total'), onError)
  .then(summarize, onError)
  .then(send, onError);