JSON API Serializer and DeSerializer

index.js

// JSON API deserializer as express middleware
app.use((req, res, next) => {
  if (req.headers['Content-Type'] === 'application/json' || _.isEmpty(req.body)) {
    return next();
  }
  var model = new JSONAPIDeSerializer({}, req.body);
  // Only pick not (null or undenfined) attributes
  model = _.pick(model, (attr) => {
    return attr !== null && attr !== undefined;
  });
  req.model = model;
  next();
});

orders.js

var Express = require('express');
var Order = require('ec-domain').Order;
var debug = require('debug')('ec-api:orders');
var _ = require('lodash');
var Q = require('q');
var relationships = require('./relationships');
var Serializer = require('../serializers');
var OrdersSerializer = require('../serializers/orders_serializer');

var app = new Express();

app.use('/:id/relationships', relationships);

/**
 * Routes
 */
app.route('/:id?')
  .all((req, res, next) => {
    next();
  })

/**
 * POST
 */
.post((req, res, next) => {
  var newOrder = req.model;
  _.merge(newOrder, Serializer.normalize(req.body.data.relationships));

  return Order.create(newOrder).then((order) => {
    debug('order created', order.id);
    const jsonapi = new OrdersSerializer(order.toObject()).serialize();
    return res.status(201).send(jsonapi);
  }, next);
});

module.exports = app;

serializer.js

var _ = require('lodash');

// relationships comes in { plan: { id: '1-shirt' } }
// but because we are using Mongoose, id doesn't allow us to use plain JS objects
// so we need to extract ids
function normalize(relationships) {
  var normalizedData = {};
  relationships = relationships || {};
  Object.keys(relationships).forEach((k) => {
    let key = _.camelCase(k);
    let relationData;
    if (_.isArray(relationships[k])) {
      if (_.isEmpty(relationships[k])) {
        relationData = [];
      } else {
        relationData = relationships[k].data;
      }
    } else {
      relationData = relationships[k] ? relationships[k].data : null;
    }
    if (!relationData) {
      return;
    }
    if (_.isArray(relationData)) {
      normalizedData[key] = relationData.map((relationObject) => relationObject.id);
    } else if (relationData.id) {
      normalizedData[key] = relationData.id;
    } else {
      normalizedData[key] = null;
    }
  });
  return normalizedData;
}

module.exports.normalize = normalize;