text: 'use strict';
  
  var ExchangeRateService = {};
  
  /**
   * Module dependencies.
   */
  var Promise				= require('bluebird'),
  	mongoose 			= require('mongoose'),
  	ExchangeRateEntity 	= mongoose.model('ExchangeRate');
  
  module.exports = ExchangeRateService;
  
  ExchangeRateService.fnRead = function(sellerRole, sourceCurrency, destinationCurrency) {
  	return ExchangeRateEntity
  	.findOne()
  	.where('sellerRole').equals(sellerRole)
  	.where('sourceCurrency').equals(sourceCurrency)
  	.where('destinationCurrency').equals(destinationCurrency)
  	.where('fromDate').lt(Date.now())
  	.sort('-fromDate')
  	.select('-fromDate -createdDate -sellerRole -id')	
  	.exec();
  };