Building Multi-Container Application And Deploying to AWS Elastic Beanstalk Using Travis CI

Containers

• Nginx
• Redis (AWS Elasticache)
• Postgres (AWS RDS)
• React (client)
• Express (api server)
• Worker (calculator)

Descriptions

• Browser sends the request to Nginx server, which routes the request to respective location
• Request coming from browser with '/' path requesting (HTML or JS) is directed to react/client server located at port 3000.
• Request coming from browser with '/api' path (submitting or retrieving values) is directed to express/api server located at port 5000
• All the submitted values are stored in Postgres database for permanent storage
• All the submitted and calculated values are stored in Redis database as key-value pairs
• If the number submitted is previously seen, it will return the calculated value from Redis server, otherwise it is sent to worker container for the calculation
• Nginx, Express, React and Worker server are hosted on AWS Elastic Beanstalk
• Redis server is hosted on AWS Elasticache
• Postgres database server is hosted on AWS RDS
• Every new version is deployed on AWS EB, as we push our code changes to Github, which is build, tested and deployed using Travis CI

Redis/Postgres is separated from AWS EB because:

• AWS automatically creates and maintains Redis/Postgres instance for us
• Super easy to scale
• Built in logging + maintenance
• Better security
• Easy to backups