esrislurp.js

/*
 * esrislurp
 * https://github.com/steveoh/esrislurp
 *
 * Copyright (c) 2014 steveoh
 * Licensed under the MIT license.
 */

'use strict';
var fs = require('fs'),
  path = require('path'),
  async = require('async'),
  http = require('http'),
  beautify_js = require('js-beautify').js_beautify,
  beautify_css = require('js-beautify').css,
  mkdirp = require('mkdirp'),
  os = require('os'),
  request = require('request'),
  unwind = require('./unwinder');

var endsWith = function(s, suffix) {
  var l = s.length - suffix.length;
  if (l >= 0 && s.indexOf(suffix, l) === l) {
    return true;
  }
  return false;
};

var ensureRight = function(s, suffix) {
  if (endsWith(s, suffix)) {
    return s;
  }
  return s + suffix;
};

function noop() {}

module.exports = function(basePath, version, beautify, onSuccess, onError, onProgress) {
  onSuccess = onSuccess || noop;
  onError = onError || noop;
  onProgress = onProgress || noop;

  var packageLocation = ensureRight(basePath, path.sep);
  mkdirp.sync(packageLocation);

  // reuse open connections by setting keepAlive true
  var agent = new http.Agent({keepAlive: true});
  var esriModules = require('./modules/esriModules-' + version);
  var esriVersionBaseUrl = 'http://js.arcgis.com/' + version;

  var versionParts = version.split('.');
  var major = parseInt(versionParts[0]);
  var minor = parseInt(versionParts[1]);
  if (major >= 3 && minor > 10) {
    esriVersionBaseUrl += 'amd/esri/';
  } else {
    esriVersionBaseUrl += 'amd/js/esri/';
  }

  var total = esriModules.length,
    count = 0;

  function signalProgressUpdate() {
    onProgress({
      count: count,
      total: total
    });
  }

  async.eachLimit(esriModules, 50, function(file, callback) {
    var subPath = ensureRight(path.dirname(file), '/'),
      fileFolder = path.join(packageLocation, subPath),
      fileName = path.basename(file),
      httpUrl = esriVersionBaseUrl + subPath + fileName;

    if (!fs.existsSync(fileFolder)) {
      mkdirp.sync(fileFolder);
    }

    request.defaults({agent: agent})({
        uri: httpUrl,
        encoding: 'binary'
      },
      function(error, response, body) {
        count += 1;

        if (error) {
            signalProgressUpdate();
            return callback(error);
        }

        // likely a 404, resume next by exiting on the callback
        if (!body) {
          signalProgressUpdate();
          return callback(null, body);
        }

        var newFile = path.join(packageLocation, file);

        var extension = path.extname(file);
        if (extension === '.js' || extension === '.css') {
          body = unwind(body);

          if (beautify) {
            try {
              if (extension === '.js') {
                body = beautify_js(body);
              } else if (extension = '.css') {
                body = beautify_css(body);
              }
            } catch (e) {
              console.warn(os.EOL + 'error beautifying: ' + file + ' ' + e);
              // swallow it's not the end of the world if it's not beautiful
            }
          }
        }

        fs.writeFile(newFile, body, 'binary', function(err){
          if (err) {
            console.warn(err);
          }
          signalProgressUpdate();
          return callback(err, body);
        });

      });
  }, function(err) {
    if (err) {
      onError(err);
    } else {
      onSuccess();
    }
  });
};