DynamoDB model helper (with promise wrapper)

abstract.js

const DynamoDB = require('aws-sdk/clients/dynamodb')
const documentClient = new DynamoDB.DocumentClient({
  apiVersion: '2012-08-10',
  // logger: console
})

module.exports = class Model {

  /**
   * Model constructor
   * 
   * @param {String} tableName 
   */
  constructor(tableName) {
    this.tableName = tableName
  }

  /**
   * DynamoDB query wrapper
   * 
   * @param {*} params
   */
  async query(params) {
    params.TableName = this.tableName
    return documentClient.query(params).promise()
  }

  /**
   * DynamoDB get wrapper
   * 
   * @param {*} keys
   */
  async get(keys, params) {
    params = params || {}
    params.TableName = this.tableName
    params.Key = keys
    return documentClient.get(params).promise()
  }

  /**
   * DynamoDB scan wrapper
   * 
   * @param {*} keys
   */
  async scan(params) {
    params = params || {}
    params.TableName = this.tableName
    return documentClient.scan(params).promise()
  }

  /**
   * DynamoDB put wrapper
   * 
   * @param {*} item
   */
  async put(item) {
    return documentClient.put({
      TableName: this.tableName,
      Item: item,
    }).promise()
  }

  /**
   * DynamoDB batchWrite wrapper
   * 
   * @param {Array} items
   */
  async putBatch(items) {
    const requestItems = {}
    requestItems[this.tableName] = items.map((item) => ({
      PutRequest: {
        Item: item
      }
    }))

    return documentClient.batchWrite({
      RequestItems: requestItems
    }).promise()
  }

  /**
   * DynamoDB batchWrite wrapper
   * 
   * @param {Array} items
   */
  async deleteBatch(keys) {
    const requestItems = {}
    requestItems[this.tableName] = keys.map((key) => ({
      DeleteRequest: {
        Key: key
      }
    }))

    return documentClient.batchWrite({
      RequestItems: requestItems
    }).promise()
  }

  /**
   * DynamoDB update wrapper
   * 
   * @param {*} params
   */
  async update(params) {
    params.TableName = this.tableName
    return documentClient.update(params).promise()
  }

}

todo.js

const AbstractModel = require('./abstract')

class Model extends AbstractModel {

  /**
   * Custom method
   */
  async isDone(id) {
    const doc = await this.get({id})
    return doc.done === true
  }

}

module.exports = new Model(process.env.TABLE_TODO)