Api - Dynamodb example

Api rest using dynamodb as DB. The idea is to show with a real example some best practices, dynamodb implementation, the use of localstack, docker-compose to run all locally and some extra things like unit tests with jest and swagger.

## Technologies/tools used

• node js
• express
• localstack (for dynamodb)
• docker
• docker-compose
• jest for unit testing
• swagger

Flow

The flow of every packet received is:

• index: main class where the project is started
• app: set up port, healthcheck, routes, and aws endpoint for local testing
• router: where all the routes are defined, is used in app.js
• controllers: to validate basic things needed
• models: concrete classes/models with some business logic (in this case very little)
• daos: where is the DB logic, on how to get the data and from where
• repositories: the final providers/connections, in this case the real call implementation to dynamodb

Prerequisites

• Docker [https://www.docker.com/get-started]
• docker-compose

localstack and setup

This service immitates AWS services, in this case we will use it to have a DynamoDB service locally to develop. To start it and inmediatly call setup to create tables and put some records to test run:

docker-compose up -d localstack setup

start api locally

This service is the Node API for local development. To start the app and develop right away, just run:

docker-compose up local

The API will restart automatically every time a change is made. To make requests go to http://localhost:3000

unit tests

This service runs unit tests. It also produces coverage reports. To run the unit tests:

docker-compose up test

Swagger

• This project implements a swagger ui. To view it just go to: http://localhost:3000/docs

Can be tested thru swagger

Test Methods by CURL

Insert

curl -X POST
http://localhost:3000/v1/messages/
-H 'Content-Type: application/json'
-H 'Postman-Token: d08335d8-f150-4f45-9471-0b484effc257'
-H 'cache-control: no-cache'
-d '{ "sender": "user1", "receiver": "user2", "mid": "mid4", "msg": "test insert", "ts": 1562969043 }'

get sent

curl -X GET
'http://localhost:3000/v1/messages/sent?sender=user1'
-H 'Postman-Token: 49250d20-5287-4061-9c5c-3f47d7251b3b'
-H 'cache-control: no-cache'

get received

curl -X GET
'http://localhost:3000/v1/messages/received?receiver=user1'
-H 'Postman-Token: e28723d5-ad0d-4aa5-8f2c-9f642ee7c66a'
-H 'cache-control: no-cache'

update message

curl -X PATCH
http://localhost:3000/v1/messages/
-H 'Content-Type: application/json'
-H 'Postman-Token: 1c9d587f-3e69-452a-ae71-830f396b9319'
-H 'cache-control: no-cache'
-d '{ "sender": "user1", "mid": "mid4", "msg": "test insert" }'