SpringRedisSample

This is a sample application demonstration redis caching capabilities in Spring Boot. This app is also deployable to AWS ElasticBeanstalk and integrates with AWS ElastiCache.

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Reach out to Me

• LinkedIn - Manthan Patidar
• Slack - Manthan Patidar
  • Reachable only by Scaler students

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Application Overview

• A simple post management system allowing Read operations on and Posts using SQLite DB as persistence store.
• During the startup sequence, the project seeds dummy data into the SQLite database to have something to play with. This is done via the SeedData class within startup package.

Note: All data is wiped (from both SQLite DB as well as ES) on every reboot of the app.

• The app has 3 endpoints
  • GET / -> Hello world endpoint which redirects to /actuator/info
  • GET /posts/ -> Get all posts
  • GET /post/{postId} -> retrieve post by id
    • The initial call will take 4 seconds to respond - but subsequent calls will be much faster thanks to reading from redis cache. The TTL for entries in cache is set to 30 seconds.

Note: As we are using SQLite database, the code intentionally includes a 4 second delay to simulate a proper (over network) DB call.

• Refer postman folder for collection & environment (you can import in postman)

Spring Profiles

The Spring Boot project contain multiple application.yaml files accounting for multiple environments/profiles

• application-local.yaml
  • is used when running the project locally via IntelliJ and uses the dependencies running in docker containers (or you can also setup other locally running dependencies)
• application-aws.yaml
  • is used when the app is deployed on AWS Elasticbeanstalk and uses AWS Elasticache

The above profiles can be switched at runtime by setting the environment variable,

SPRING_PROFILES_ACTIVE=aws

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Running Locally

• Open the project in IntelliJ
• Make sure the redis server is running before you run the project
  • redis server can be setup via docker or by any other means (docker setup can be achieved by running the provided docker-compose.yml file in the docker folder)

Running on AWS

• Setup AWS ElastiCache (steps mentioned below)
• Copy the AWS ElastiCache endpoint & port in application-aws.yaml file
• Create a .jar file
• Setup AWS ElasticBeanstalk and deploy the .jar file.

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AWS ElastiCache Setup

1. Go To AWS Elasticache > Redis OSS Cache > Create and then select the following configuration options

2. Disable Cluster Mode - as this is just for demo we dont need multiple shards

3. Set cache name (and optional description)

4. Set Location and make sure to disable MultiAZ and Auto Failover to save some bucks

5. Cluster Settings

   • Parameter groups -> default.redis7
   • Make sure to select smallest node type -> cache.t2.micro
   • And set number of replicas to 0

6. Subnet group settings

   • Provide a name and select a VPC
   • this will determine the placement of redis cache in the subnets and therefore its reachability from other subnets
   • it is preferred to select only private subnets
   • but as this is just for demo, I've selected all subnets available in the VPC

7. Availbility Zone Placements -- NO CHANGE

8. Security

   • Disable Encryption at rest
   • Disable Encryption in transit
   • Select default security group of the VPC

9. Backup

   • Disable as this is just for demo/learning purposes

10. Maintenance

    • Disable Auto upgrade minor versions

11. Logs

    • Disable Slow logs
    • Disable Engine logs

12. Hit Create

    • it takes about ~10 minutes to become available

13. Once created the endpoint is available here