If you’re new to the world of microservices, read on for a quick overview of the benefits it will bring to your development efforts.

Microservices are an alternative approach to the monolithic architecture that has been the standard of software development for decades. Monolithic architectures have a long history of success and have been universally supported by many software vendors and industry experts. However, times change, and new technological developments emerge to prove more beneficial than what everybody seems to be used to.

In this article, we are going to dig into how microservices work, what makes them better than a monolithic application architecture, what flaws they may have, and how to deal with that. And last but not least – what companies have gone for the microservices architecture and never regretted it.

What are microservices and how do they work?

Microservices, or also known as a microservices architecture, are a modern software development technique and an architectural style applied to achieve business goals through decomposing an interdependent software system into smaller, more autonomous units. These modules work together and communicate with one another but are deployed independently. With the microservice architecture, developers can create separate modules that would work as a selection of individual services. Together, they also ensure the application can be highly performant while supporting its full-featured functionality.

Ideally, a microservice-based application should have multiple independent components – each responsible for a specific function – that are distributed, secured, and kept in sync via various communication channels. Each component should stay in touch with all other components in order to fully understand and support all network activities and future needs of the system. Therefore, it is a common practice to split one project team into smaller teams, each involved in the development of a single microservice.

When we talk about a monolithic application, the technology stack may be as varied, balanced, and complex as it is required to satisfy specific business needs on a particular project. However, even if the monolithic app follows service-oriented architecture, these services can grow with time to become globs supporting dozens of functionalities.

In turn, when developing a microservice-based app, the team will most probably need to prioritize product mentality over the project itself. This means the product must consist of microservices that should have few functionalities to support throughout the whole project’s existence.

For microservices to work harmoniously with one another, the development team has to set up a structure in which direct and fast communication is established. Therefore, from what has been said here, it follows that – no matter whether you’re developing a microservices-based app from scratch or converting an existing monolith – the basic technologies needed to build an application with a microservices-based architecture are going to be more or less the same:

• REST API. In a general setup, inter-component communication between microservices must be established via a lightweight messaging mechanism. REST API can provide this simple API-based synchronous messaging solution to embed the connection between microservices in a distributed system. Implemented with HTTP request-response, it makes an app more resource-oriented so that each functionality is represented with a resource and corresponding operations carried out on top of that resource. REST/HTTP synchronous messaging allows developers also to use the following:
  • JSON and XML message formats
  • Swagger and RAML definition languages
• Docker. Fundamentally, Docker is a container-based virtualization and infrastructure technology whose distributed nature gives developers greater control over resources and features. Moreover, Docker has multiple benefits for a microservice-based app. It simplifies app development, deployment, and maintenance through containerization. It is an excellent fit for a microservices architecture as it enables encasing the developed software in containers so that one container would support one service or functionality. Docker Machine, Docker composer, and Docker Swarm can then also be used to manage those containers in the most efficient and scalable way.
• Gateways. With no business logic implemented on it, the gateway can serve as a lightweight dumb pipe for a transferred message. Thus, microservices get exposed through API gateways as through the entry points. And so, not only different APIs can be applied to different microservices, but also they become more lightweight. Besides, API gateways can, in some cases, enable service discovery. For instance, Kubernetes allows for server-side service discovery, in which API-GW is in a position to send requests determining the location of the microservice.
• Decentralized data management. Decentralization is an essential part of a successful microservices implementation. Thus, each microservice must have its own private database so that no other microservice could access it. This makes microservices highly decoupled and lets developers choose the appropriate data management technique (SQL/NoSQL) for each separate microservice depending on what business logic stands behind it.

When to use the microservice architecture?

Using the microservices architectural style is something beyond splitting services in a monolith. Therefore, the number of cases, in which it is generally recommended to implement, is larger than it may seem first. For many, microservices are a new concept, and some may not understand upfront the innovation that they suggest. So, let us clarify and say that microservices are a good idea:

• When it is imperative for the system components to be able to communicate with one another seamlessly.
• When an application is growing more massive, and simply building more modules and moving them to production is not an option.
• When a business has all the necessary resources to invest in the development of a microservice-based application in advance once the project starts, which also means hiring the right specialists.
• When a business prioritizes the long-term benefits to the short-term positive outcome for the project, which is what a microservices architecture incurs.
• When the application under development is going to be resource-consuming, with lots of traffic going to and fro.

Benefits of a microservices architecture

Many organizations, whose applications have been previously based on a monolithic architecture, are now moving them to microservices exactly because the advantages of a microservices architecture have already been proven and realized by other players on the global field.

The benefits of the microservices architecture include continuous delivery and deployment, better scalability, improved fault isolation, greater flexibility, smaller development teams, higher software testability, and improved maintainability.

1. Continuous delivery and deployment - This is a big plus, especially in the case of large, complex applications. Continuous delivery and deployment are two critical components of an effective software development process. And for microservices architectures, where apps work as suites of independently deployable services, they become particularly important. As the microservice architecture gives the project team the freedom to develop and deploy services separately from one another, the capabilities derived from continuous delivery and deployment help the team get any changes into production in a safe and sustainable manner. These practices are more easily implemented with the microservices-based than monolithic architecture. As a result, deliverable throughput and resource utilization are considerably improved.

2. Better scalability - Microservices are far more scalable than a monolith. Although different microservices in a system may have different resource requirements and performance limitations, compared to a monolith, they still are relatively small, so they are easier to scale and integrate with third-party services. And despite the fact that such ecosystems are usually large-scale and distributed, they are at the same time concurrent. Concurrency is a significant characteristic of a scalable application, and microservice ecosystems allow for that. This way, tasks are broken up into smaller sub-tasks and processed in parallel within the microservice architecture. As a result, they are executed much faster than if they were implemented in a monolithic application, which, in turn, enables and supports a scalable deployment pipeline.

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