json-schema-dynamo

If you are able to, please consider using the DocumentClient in the AWS.DynamoDB SDK as it makes this package mostly unnecessary.

An easier way to transform objects into DynamoDB items

var transformers = require('json-schema-dynamo')

var schema = {
  type: 'object',
  properties: {
    id: {
      type: 'string'
    },
    createDate: {
      type: 'date'
    },
    name: {
      type: 'string'
    },
    active: {
      type: 'boolean'
    },
    likes: {
      type: 'number'
    },
    types: {
      type: 'array',
      items: {
        type: 'string'
      }
    },
    userIds: {
      type: 'array',
      items: {
        type: 'number'
      }
    }
  }
}

var model = {
  id: 'asdf',
  createDate: new Date(),
  name: 'asdffdas',
  likes: 1,
  active: true,
  types: ['qwerty', 'ytrewq'],
  userIds: [1, 2, 3, 4, 5, 6, 7]
}

var item = transformers.fromModelToDynamoItem(schema, model)
console.log(item)
/*
  {
    id: {
      S: 'asdf'
    },
    createDate: {
      N: '1928383'
    },
    name: {
      S: 'asdffdas'
    },
    likes: {
      N: '1'
    },
    active: {
      B: 'true'
    },
    types: {
      SS: ['qwerty', 'ytrewq']
    },
    userIds: {
      SN: ['1', '2', '3', '4', '5', '6', '7']
    }
  }
*/

var newModel = transformers.fromDynamoItemToModel(schema, item)
console.log(newModel)
/*
  {
    id: 'asdf',
    createDate: <Date>,
    name: 'asdffdas',
    active: true,
    likes: 1
    types: ['qwerty', 'ytrewq'],
    userIds: [1, 2, 3, 4, 5, 6, 7]
  }
*/

Currently it supports: string, number, integer, boolean, array of strings, array of numbers, and lists

There is also custom support for dates. You can define an attribute as a date type which will be transformed into an N in Dynamo and then back into a date when retrieved.

Both transforms will also validate your model against your schema as well