Building microservice systems with docker and kubernetes

BUILDING MICROSERVICE SYSTEMS WITH DOCKER AND KUBERNETES FULL
BUILDING MICROSERVICE SYSTEMS WITH DOCKER AND KUBERNETES CODE

Source CodeДeveloper-level members of my CodeOpinion YouTube channel get access to the full source for the working demo application available in a git repo. No, Microservices are about logical separation, not physical. IвЂ™m not advocating one way or the other, but illustrating that logical separation and physical separation are different concerns.Дo Microservices require Containers/Docker/Kubernetes? They are simply hosted together in the same process. They arenвЂ™t directly communicating within the same process. However, you can still have logical separation without physical separation of deployment.ДЄt build time, you could however compose all the different services and run them within the same executable. In the example above, each Service (Sales, Warehouse, Billing) are all living in their own containers, talking to their own databases and communicating to a message broker. In most examples of Microservices, they focus as if these are all one unified concept without making any distinctions between them. The physical view is the topology of deployment. The Development view represents the source code, repository, what you see in your editor or IDE. The logical view represents a bounded context. ItвЂ™s used for describing an architecture based on multiple concurrent views.

The above diagram is the 4+1 Architectural View Model. !Original: MddVector: Wikimpan, CC BY-SA 3.0, via Wikimedia Commons

BUILDING MICROSERVICE SYSTEMS WITH DOCKER AND KUBERNETES CODE

Somewhere along the rise of Microservices became this idea that a logical boundary is also a single source code repository that is built into a single deployable unit.ДЇor example, that a service had itвЂ™s own git repository and would be built into a container image.ДЄlthough this is practical in some situations, it doesnвЂ™t need to be if you think about logical, development, and physical views separately. It represents a portion of a subdomain of the larger system. Microservices is about logical separation, not physical.ДЄ bounded context is a logical boundary. But this is missing the point entirely of Microservices. The focus then becomes on Containers, Docker, Kubernetes, or Serverless. The vast majority of the content youвЂ™ll find about Microservices, almost always focus on physical deployment and all the technical complexities that come from it. This is why I like to describe a service as the authority of a set of business capabilities. I advocate often for Domain-Driven Design and the concept of boundaries in most of my posts/videos. If youвЂ™re sharing a database with other services, and make a schema change and need to coordinate with other services so they also make the required change, you arenвЂ™t autonomous. If you have to coordinate with another service for a change your making, then youвЂ™re not autonomous. You want to be autonomous and not be coupled to other services. If you have to know too much about surrounding services you donвЂ™t have a bounded context. When it comes to a Bounded Context, which is from Domain-Driven Design Loosely coupled service oriented architecture with bounded contexts IвЂ™ll use the definition from Adrian Cockcroft: I think Microservices falls into that category as I donвЂ™t think you would get the same definition from a group of people. Martin Fowler calls this Semantic Diffusion. Like many terms in the industry, they often get confused or conflated with other concepts and lose their original meaning. Video canвЂ™t be loaded because JavaScript is disabled: Do Microservices require Containers/Docker/Kubernetes? ()

Building microservice systems with docker and kubernetes