get-translation/libraries/search.js

Effective translation workflow

/**
 * Module dependencies
 */

var lunr = require('lunr')
  , file = require('./file')
  , log = require('./_log')
  , EventEmitter = require('events').EventEmitter
  , util = require('util')
  , fs = require('fs');

/**
 * Add terminal colors
 */

require('terminal-colors');

/**
 * We need to search in both `gt search` and in the interface. This object
 * provides indexing and query functions.
 *
 * @constructor Search
 */

var Search = function() {
  if (!(this instanceof Search)) return new Search();

  EventEmitter.call(this);

  this.translations = null;
  this.store = pcf.store;
  this.logLength = pcf.LOG_LENGTH;
  this.index = null;
  this.defaultLocale = pcf.defaultLocale;
  this._createIndex();
};

/**
 * Inherit EventEmitter
 */

util.inherits(Search, EventEmitter);

/**
 * Create search index
 *
 * @return {void}
 * @api private
 */

Search.prototype._createIndex = function() {
  this.index = lunr(function() {
    this.ref('id');
    this.field('key', { boost: 10});
    this.field('text', { boost: 10});
  });
};

/**
 * We need to read all translations and append translations to the index
 *
 * @return {void}
 * @emit `readend`
 * @api public
 */

Search.prototype.readTranslations = function() {
  // Store translations for searching later
  this.translations = file.readTranslations();

  if(typeof this.translations[this.defaultLocale] === 'undefined') {
    throw new TypeError('Default locale is undefined');
  }

  this.translations = this.translations[this.defaultLocale];

  for(var key in this.translations) {
    var translation = this.translations[key];
    this.index.add({
      id : translation.key,
      text : translation.text,
      // the key `BASE__EXIT_BUTTON` should be toknized as `base exit button`
      key : translation.key.replace(/_+/g,  ' ').toLowerCase()
    });
  }

  // Save docs
  this.docs = this.translations;

  this.emit('readend');
};

/**
 * Query translations
 *
 * @param {String} q
 * @return {void}
 * @api public
 */

Search.prototype.queryOutput = function(q) {
  var _this = this;

  var res = this.index.search(q).slice(0, this.logLength);

  if(res.length === 0) {
    log.log('No result found');
  }

  var n = 1;
  var cache = [];
  for(var i in res) {
    log.log((n === 10 ? '%' + n : ' %' + n).yellow + ' ' + this.docs[res[i].ref].key + ' | '  + this.docs[res[i].ref].text.green);
    cache.push(res[i]);
    n++;
  }

  // Store as cache
  fs.writeFile(
    pcf.searchFile,
    JSON.stringify(cache, null, 2),
    function() {
      _this.emit('queryend', res);
    }
  );
};

/**
 * Query translations
 *
 * @param {String} q
 * @return {void}
 * @api public
 */

Search.prototype.query = function(q) {
  var _this = this;

  return this.index.search(q).slice(0, this.logLength).map(function(result) {
    return {
      id: _this.translations[result.ref].id,
      key: result.ref,
      value: _this.translations[result.ref].text
    };
  });
};

/**
 * Exports instance
 */

module.exports = Search;

/**
 * Exports constructor
 */

module.exports.Search = Search;