RHTODO

A ReST API for TODOs.

Design

This explores the Command-Query Responsibility Segregation (CQRS) and Event Sourcing paradigm in a serverless environment on AWS.

This architecture is naturally reactive and virtually unconstrained in scalability and querability. The domain model is independent of any particular storage, making it very testable and strict in maintaing the domain rules. Data with business relevance is never thrown away.

The solution is based on:

• API Gateway
• Lambda
• DynamoDB and DynamoDbStreams
• Elasticsearch

Possibly Coming soon

• AWS IoT (serverless websocket notification)
• Cognito (authentication)
• CI/CD pipeline

Disclaimer

While a good showcase of CQRS/ES/DDD, this is still weekend-level code and a just a fun exploration of technologies. Many corners were cut.

Development requirements

• Node v8.10
• npm 6.4.1
• aws cli 1.11.133

Running tests

Export AWS credentials and AWS_REGION variables. Then run

$ npm run test
$ npm run test-integration
$ npm run test-system

Deployment

To deploy an individual environment:

$ scripts/dev.sh deploy

Accessing Elasticsearch

To query Elasticsearch freely:

docker run --rm -p 9200:9200 -it -v $HOME/.aws:/root/.aws -e AWS_PROFILE=$AWS_PROFILE abutaha/aws-es-proxy \
  ./aws-es-proxy -endpoint "<endpoing>" -listen 0.0.0.0:9200