Modernizing Monolith to Microservices
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This is a pretty good question to ask before dedicating the time and resources needed to move to Microservices. What are the overall goals of the organization and what characteristics of the application architecture will best help achieve these goals? The pros and cons of moving to a Microservices architecture are equally compelling. Many organizations that use Microservices are much faster, more resilient and more flexible than the ones who don’t.
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Microservices architecture denies many monolithic problems that can create technical debt and brings measurable cost savings in both time and speed to the market. Microservices offer much more flexibility while deploying or updating the application. This carries over the more efficient overall application development process. Also, Microservices enable an application to be far easier to scale, which aligns with any existing or potential cloud strategy.
Now there is an understanding of what monolithic and Microservices bring to the table, it’s time to think about approaching the technical transition. There are different strategies discussed below.
The first thing to figure out before starting the transition is what services are needed to make or break the monolithic codebase and what your architecture will look like in a completed Microservice architecture, how big or how small you want them to be, and how they will be communicating with each other. A starting point is to examine those boundaries negatively impacted by the monolith, for example, those that you deploy, change or scale more often than the others.
Transitioning to Microservices is effectively a refactoring. As the transition proceeds, so do changes to how the system fundamentally works. It’s important to be mindful that, post the transitional phase, all the functionalities that once existed in the monolith are still working in the re-designed architecture.
A best practice is that before attempting any change, a solid and reliable suite of integration and regression tests put into place for the monolith. Some of these tests will fail but having well-tested functionality will help to track down what is not working as expected.
The vital issue with Microservices is that the way services use other services can become incredibly complex. Testing, configuration, and deployment often require automation due to the sheer number of services affected by a change to just one. Besides, you have to manage each individual service and scale it as needed. Automation tools are almost always a necessity.
With an architecture that gives services their own database, entering data isn’t as straightforward as it is with a monolithic architecture. The entry data split up and is sent to the correct service. When you have a large number of services, this kind of data handling can be challenging.
You must take your application and its users into consideration. In case, your application is small, has low complexity, doesn’t need pinpoint scalability. It may be more trouble than it is worth to re-design the architecture.
The migration of an existing application into Microservices is a form of application modernization. You should not move to Microservices by rewriting your application from scratch. Instead, you must incrementally refactor your application into a set of Microservices.
There are three strategies to follow:
- Implementing new functionality as Microservices.
- Splitting the components from the business and data access elements.
- Converting existing applications in the monolith into Microservices.
Over time the number of Microservices will grow, and the agility and velocity of your development team will increase. Approaching this migration cannot achieve without a long-term plan and preparation tasks that will help with a successful transition, including a good testing strategy.
It will include transition implementations built along the way, that will remove later, for example when dealing with legacy database, authentication or authorization functionality. But once the transition is complete, a Microservice architecture will enable the organization to be far nimbler and enable greater velocity in the evolution of the application.
Techcello offers consulting services where our experts engage with you and help you design Microservices using industry best practices. It has predefined architectural blueprints for software architecture, deployment architecture on AWS/Azure and DevOps. Techcello provides agility, elasticity, improved cost predictability while enhancing security and better operational control.
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