Microservices architecture is a hot topic in today’s software industry. Software development processes have advanced significantly, and microservices has long been regarded as an advanced architecture pattern and the preferred choice for enterprises developing software. 

As demonstrated by the industry today, breaking down a massive asynchronous software ball into smaller, more manageable pieces has enormous benefits. Microservices architectures lead to improved software development, monitoring, functionality, and speed.

This article will cover a variety of critical aspects of microservices.

Why are microservices necessary?

Software development has become simpler thanks to developer tools and platforms such as Docker, Kubernetes, AWS, and GitHub, which help break up the millions of lines of code from a single monolithic architecture into smaller and more manageable “micro” elements.

Previously, it was difficult to make changes to the code base or to release new features, resulting in delays and conflicts between developer teams. And when something went wrong, identifying the error was a monumental task.

The operations team blames development, and development blames QA. Due to the fact that the errors are invisible, a blame game ensues. It’s difficult to determine which code caused the production to fail and who or which team is responsible for the error.

This is where microservices architecture excels.

While a monolithic application contains all of its functionality in a single code base and scales through replication across multiple servers, a microservices architecture separates an application’s functionality into several smaller services. It then categorises them according to logical domains (e.g., authentication, user directory, reporting, checkout, etc.). Microservices communicate with one another via APIs to create what appears to end users as a single application.

They have well-defined boundaries and are straightforward to develop, test, deploy, and scale.

That’s why numerous businesses have recently migrated from their colossal monolithic architecture to a microservices architecture in anticipation of a bright future. 

 What distinguishes microservices from traditional development processes?

 In a traditional monolithic application architecture, all of the code components are designed as a single, cohesive unit with interconnected but independent components. Any updates required by developers result in changes to the entire stack. Switching to a new technology stack or framework necessitates a significant code overhaul and rewrite.

 By comparison, a microservices architecture divides the system into independent services that can run as autonomous processes and communicate with one another via application programming interfaces (APIs).

Containerization enables services to be encapsulated and operations to run in parallel, simplifying the maintenance of existing infrastructure. Individual services can be updated or changed without affecting the entire system.

Microservices architecture (Image courtesy: Cloud Application Architecture Guide).

Advantages of microservices:

• Scalability of a small work team
• Module-based functionality, self-contained modules
• Developer independence in developing and deploying services
• Utilization of containers, which enables rapid deployment and development of the application
• Simplified process of locating and resolving bugs
• Reduced startup time due to the use of lightweight servers.

How Microservices benefits teams 

Architects: Simple to design. Rather than developing the entirety of Facebook as a single app, if they view the various components as microservices (newsfeed, chat, etc.), it becomes much easier for architects to decide how each should look, function, and interact. Additionally, it will be simpler to define failure scenarios (e.g. if chat microservices go down, the news feed will still be available for customers).

Developers: If you tell a developer to create a feature – for example, a clear distinction between notifications for newsfeed and messages on Facebook – they will be able to make code changes. They simply add a few lines to the newsfeed microservice and, most likely, to the chat microservice as well. This simplifies the job and boosts productivity. 

Engineer, DevOps: Consider a scenario where the chat microservice requires some code updates; updating the other microservices in production would be superfluous.

Micro services-enabled businesses

 Spotify.com

 Spotify has over 75 million monthly active users, and it’s fascinating to see how the company uses microservices to manage the system efficiently. The goal is always to create a seamless customer experience.

Spotify manages this as follows:

• Spotify’s system is divided into self-contained and single purpose microservices, each with its own team of developers. Each microservices team is referred to as a squad.
• Each microservice at Spotify is associated with a specific objective. For instance, a search engine, behavioral analytics on users, and song recommendation engines.
• These services are significantly less reliant on one another operationally. As a result, customer service is quick and consistent, and the company can quickly resolve issues without affecting other services. Spotify uses microservices in this way to reduce the risk of its services going down and to increase overall efficiency.
• At Spotify, developers deploy microservices independently and are responsible for their own operations. They are provided with tools that make provisioning and deployment simple.

WIX

 Wix’s architecture was unique in that it utilized a massive Java monolith (along with Hibernate, Ehcache, Tomcat, and MySQL) to manage everything, from user registration to login to editing Wix sites and serving content; it handled it all.

Wix eventually abandoned Hibernate and Ehcache. It took 4.5 years to de-monolithize Wix; the process was complicated by the fact that they kept Wix running and adding new features while gradually moving components from the monolith to new microservices. Wix now has over 100 microservices.

Wix adopted microservices to eliminate a significant amount of technical debt that had accumulated and caused critical stability issues within the platform. Due to the interconnected nature of Wix’s applications, bugs in one part of the system could bring the entire system down. In early 2010, Wix began dismantling the monolith into more autonomous services in order to better manage scalability and quality assurance.

Netflix

 When discussing microservices, you cannot ignore Netflix.

Netflix began its journey with microservices in 2008, long before the term microservices entered the DevOps lexicon. Netflix began experiencing service outages and scaling difficulties in 2008. It suffered severe database corruption, which resulted in a three-day delay in operation and a significant decrease in revenue.

This was the point at which Netflix recognised that it needed to transition away from vertically scaled, single points of failure and towards horizontally scalable, cloud-based distributed systems. This resulted in their decision to use Amazon Web Services (AWS) as their cloud provider.

In 2009, Netflix began a gradual refactoring of its monolithic architecture into microservices. They began by migrating their non-customer-facing, movie-coding platform to run as an autonomous and independent microservice on AWS cloud servers. The following two to three years were spent converting Netflix’s customer-facing systems to microservices.

Microservices deployment

Deploying a microservices-based application is a big challenge. Numerous services will be written in a variety of languages and frameworks. Each one can be thought of as a mini application in its own right, with its own unique deployment, scaling, and monitoring requirements.

Any organization that is committed to DevOps and has adopted the Microservice architecture generally hopes to accomplish the following:

• Rapid release of features, enabling them to stay ahead of their competitors
• No downtime, helping to build their reputation

To accomplish this, the organization must have a robust system or framework in place to store all artefacts with the appropriate version number, meta tags, and description.

This is because, if any production issues arise with the current release, they will have two safe options: either patch the fix and deploy to production, or, if the fix is too complicated, simply revert to the previous state (using an artefact repository manager) without affecting the end user.

Additionally, they can use tools such as Docker to easily and efficiently deploy microservices. Each microservice is further subdivided into processes that can be run independently in Docker containers. Dockerfiles and Docker Compose configuration files can be used to define everything in this section.

In large-scale deployments, they can leverage popular provisioning tools such as Kubernetes to manage and run a cluster of Docker containers across multiple hosts, incorporating co-location, replication control, and service discovery features to ensure a robust and efficient deployment.

Final thoughts

 While the business benefits of migrating to a microservices architecture are immeasurable, the process must be carefully monitored and implemented strategically. Adopting a DevOps culture that is backed up by robust monitoring is critical for a successful transition to a microservices architecture. Increased flexibility and speed must be balanced against an accompanying increase in complexity.