Purchase Schema

PurchaseSchema.js

var vogels = require('vogels'),
Joi = require('joi');
vogels.AWS.config.loadFromPath('./config.json');

var Purchase= vogels.define('Purchase', {
  hashKey : 'uid',
  rangeKey: 'tok',
  
  // enable timestamps support 
  timestamps : true,
 
  schema : {

    uid : Joi.string().required(), 
  	tok:Joi.string().required(),
    rno: Joi.string(), 
    exp: Joi.date(), 
    pin: Joi.string(), 
    redURL:Joi.string(), 
    title: Joi.string().required(), 
    imgURL:Joi.string().required(),

    sku:Joi.string().required(),

    price:Joi.number().required(), //list price in USD?
    oid:Joi.string().required(), //order_id
    cost:Joi.number().required(), // cost to buy it in USD
    info: Joi.object(), //all other data.
  },

});


vogels.createTables({
  'Purchase': {readCapacity: 5, writeCapacity: 5}, // note: doesn't support updating throughput 
}, function (err) {
  if(err) {
    console.log('xxx - Error creating Purchase table', err);
  } else {
    console.log('...Purchase table is online');
  }
});



Purchase.getPurchasesByUID=function(uid, cb)
{
  Purchase
  .query(uid)
  .expressionAttributeNames({ '#t' : 'tok', '#r' : 'rno', '#e' : 'exp'})
  .projectionExpression('#t, #r, #e')
  .exec(cb);
}
 
module.exports=Purchase;

Interesting, why not use:

Purchase
.query(uid)
.attributes(['uid','tok', 'rno', 'exp', 'pin', 'redURL', 'title', 'imgURL', 'sku', 'price', 'oid'])
.exec(cb);

I wanted to show you how to use expressionAttributeNames. With this now you can use attribute names such as 'token'. The reserved words list, which DynamoDB introduced relatively recently, has around 1000 words and matches many common attribute names.