DynamockDB

Ultralight AWS DynamoDB mock for Node.js

Motivation

• Make it easy to mock DynamoDB for unit test.
• Remove the need for testing frameworks.
• Zero additional dependencies.
• Simulate DynamoDB's data storage model in local memory.

Supported DynamoDB Features

• Multiple tables
• Partition key (string)
• Sort key (string)
• Promise returns

Mocked Methods

DynamockDB mocks the following methods that are available on the AWS.DynamoDB class in aws-sdk for Node.

• getItem({ TableName, Key })
• putItem({ TableName, Item })
• query({ TableName, KeyConditionExpression, ExpressionAttributeValues })
• deleteItem({ TableName, Key })

Note:

• Key contains the partition (and optionally sort) key marshalled.
• KeyConditionExpression only supports a single, equality check against the partition key. See example below.

Example Usage

const DynamockDB = require('dynamock-db')

const db = new DynamockDB({
  table1: { pKey: 'id' },
  table2: { pKey: 'zipcode', sKey: 'streetName' }
})


await db.putItem({
  TableName: 'table2',
  Item: {
    zipcode: { S: '30309' },
    streetName: { S: '10th Street NW' },
    other: { S: 'data' }
  }
}).promise()


const { Item } = await db.getItem({
  TableName: 'table2',
  Key: {
    zipcode: { S: '30309' },
    streetName: { S: '10th Street NW' }
  }
}).promise()


const { Items } = await db.query({
  TableName: 'table2',
  KeyConditionExpression: 'zipcode = :zipcode',
  ExpressionAttributeValues: {
    ':zipcode': { 'S': '30309' }
  }
}).promise()


await db.deleteItem({
  TableName: 'table2',
  Key: {
    zipcode: { S: '30309' },
    streetName: { S: '10th Street NW' }
  }
}).promise()