Monolith vs Microservices

• We have tried to install nopcommerce, architecture of this is as shown below which is a monolith application
  
• Monolith application typicall runs the whole applciation in a server and has a database (on different instance)
• Major ecommerce modules typicall are
  • Product catalog
  • Cart services
  • User Management
  • Order Management
  • Payment Services
  • Customer Services
• In monolith all the code will be in a single repository with a single technology (everything on same version)
• Advantages:
  • Works good when we have fewer modules to manage
  • Everything in a single code base and deployments are easrier
• Disadvantages:
  • Becomes difficult managing huge traffics
  • Complex deployments for simple changes
• Microservices is all about breaking down a large system into individually deployable smaller services which serve some functionality (functionally one activity)
• We can have microservice for
  • identity service
  • product catalog service
  • order service
  • cart services
  • payment services
  • Web store
• Ideally each microservice will have its own database. This gives a flexibility to choose a different technology for each service.
• Each microservice will have its own git repo.
• Each microservice is individually deployable
  
• Microservices will be communicating with each other.
• Advantages:
  • individually deployable microservices help in minimizing downtimes
  • each service can be scaled indivually
• Disdavantages:
  • Difficult to manage deployments manually
• The best place to run a microservice is a container becuase of portability.
• But we need a way to manage the microservices in production
• Challenges
  • containers going down
  • scaling containers
  • deploying new versions

Kuberentes (k8s)

• Kubernetes also known as K8s, is an open source system for automating deployment, scaling, and management of containerized applications.
• Container orchestration is what kubernetes does
• K8s supports
  • scaling containers
  • deployments with zero downtime
  • volumes
  • load balancers
  • identities