booksApp - A microservice arch template

My Sample Event-Driven Architecture:

Running on...

• a MySQL AWS RDS DB
• a AWS ES ElasticSearch query engine & AWS SQS broker
  • great Command/Query Responsibility Separation!
• lightweight k8s/Dockerorchestration for AWS EKS / EC2

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Bundled with...

2 independently scalable microservices:

1. bookService
2. customerService

• each running NodeJS / Express API
• handle biz & logic concerns
• Integrated w/AWS SQS, RDS, & ES

2 BFFs (backend-for-frontends)

1. bookBFF
2. customerBFF

• each running a Python server
• handle header parsing, auth, and response transformations
  • (on a user-client basis — ie. different responses for Desktop / Mobile)

& 1 Circuit Breaker (for an external service)

1. reccCircuitBreaker

• Sets a 3 second timeout for calls to the service and returns error codes appropriately
  • 504 - Timeout | 503 - Open Circuit | 204 - Not Found | 200 - Success

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k8s Deployment

Config files for k8s deployment are provided at the top-level project directory.

1. Apply the k8s config with: kubectl apply -f circuitBreakerConfig.yaml -f bookConfig.yaml -f customerConfig.yaml
   • Each container has a 5 second liveness check
   • The books services have 2 replicas, while customers have 1
2. See all services / pods: kubectl get all -n book-app

Other Helpful Commands**

1. See Container Logs: kubectl logs -n book-app <POD ID> <CONTAINER NAME>
2. SSH into Pod: kubectl exec -it <POD ID> -n book-app -- bash
3. Describe Pod: kubectl describe pods -n book-app <POD ID>
4. Restart Deployment (ie. after updating some container): kubectl rollout restart deployment <DEPLOYMENT NAME> -n book-app

Additional IAC / Infrastructure as Code

• All the services can be deployed via Docker (Dockerfiles provided in each respective directory):
  • See the setup script for help with docker deployment
• Setting up a Dev & Test environment (in a VM):
  • A Vagrantfile & /vagrant_scripts/ are provided for provisioning both
    • update the Vagrantfile to use whichever script you'd like
  • Install Vagrant & VirtualBox
  • run vagrant up to start the VM
  • run vagrant ssh to enter the VM
• Test scripts are provided in /tests/:
  • see the setup script for help running it

Final k8s Setup:

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