tocken和ticket的数据模型；

 /* jshint -W079 */
 /* jshint -W020 */

 "use strict";
 var _ = require("lodash");

 module.exports = function(utils, db) {

   // Model WeChatAccessTokenSchema
   var WeChatAccessTokenSchema = new db.Schema({
     appid:  {type: String, required: true },
     access_token: String,
     expires_in: Number,
     at: {type: Number, default: parseInt(new Date().getTime() / 1000)},
     create_at: {type: Date, default: Date.now}
   }, db.schema_options);

   WeChatAccessTokenSchema.index({ appid: 1 });
   WeChatAccessTokenSchema.index({ access_token: 1 });

   global.WeChatAccessToken = db.mongoose.model('WeChatAccessToken', WeChatAccessTokenSchema);

   // Model WeChatTicketSchema
   var WeChatTicketSchema = new db.Schema({
     appid: {type: String, required: true},
     ticket: String,
     noncestr: String,
     expires_in: Number,
     at: {type: Number, default: parseInt(new Date().getTime() / 1000)},
     create_at: {type: Date, default: Date.now}
   }, db.schema_options);

   WeChatTicketSchema.index({ appid: 1 });
   WeChatTicketSchema.index({ ticket: 1 });

   global.WeChatTicket = db.mongoose.model('WeChatTicket', WeChatTicketSchema);
 };