Microservices

Microservice architecture is a distinctive method of developing software systems that tries to focus on building single-function modules with well-defined interfaces and operations. The trend has grown in recent years as enterprises look to become more Agile and move towards a DevOps and continuous testing.

The distinction

Unlike microservices, a monolith application is built as a single, autonomous unit. So any changes to the application are slow, as it affects the entire system. A modification made to a small section of code might require building and deploying an entirely new version of software. So to scale a specific function of an application also means you have to scale the entire application.

Modularity is the key

Microservices solve the challenges of monolithic systems by being as modular as possible. In the simplest form, they help build an application as a suite of small services, each running in its own process and being independently deployable. These services may be written in different programming languages and may even use different data storage techniques.

Benefits Of Microservices

Simpler to deploy

Deploy in literal pieces without affecting other services.

Simpler to understand

Code is easier to follow since the function is isolated and less dependent.

Reusable across business

Share small services like payment or login systems across the business.

Faster defect isolation

When a test fails or service goes down, isolate it quickly.

Minimized risk from change

Avoid locking in technologies or languages - change on the fly with minimal risk.

Characteristics Of Microservices

• Multiple Components

It can be broken down into multiple component services. Why? So that each service can be deployed, tweaked, and redeployed independently without compromising the integrity of an application. This way, you might only need to change one distinct service instead of redeploying entire applications. But this approach has its downsides, including expensive remote calls (instead of in-process calls), coarser-grained remote APIs, and more complexity when redistributing responsibilities between components.

• Built For Business

The microservices style is usually organized around business capabilities and priorities. Unlike a traditional monolithic development approach – where different teams each have a specific focus on, say, UIs, databases, technology layers, or server-side logic – microservice architecture utilizes cross-functional teams. Each team is responsible to make specific products based on individual services communicating via message bus. In microservices, a team owns the product for its lifetime, as in Amazon’s oft-quoted maxim You build it, you run it.

• Simple Routing

Microservices act somewhat like the classical UNIX system: they receive requests, process them, and generate a response accordingly. This is the opposite to how many other products such, as ESBs (Enterprise Service Buses) work. That’s where high-tech systems for message routing, choreography, and applying business rules are utilized. You could say that microservices have smart endpoints that process information and apply logic, and “dumb pipes” through which the info flows.

• Decentralized

Since microservices involve a variety of technologies, old-school methods of centralized governance aren’t optimal. The microservices community favors decentralized governance so its developers can produce tools that can be used by others to solve the same problems. Just like decentralized governance, microservice architecture favors decentralized data management. Monolithic systems use a single logical database across different applications. In a microservice application, each service usually manages its unique database.

• Failure Resistant

Like a well-rounded child, microservices are designed to cope with failure. Since several diverse services communicate, it’s quite possible that a service could fail (e.g., when the supplier isn’t available). In these instances, the client should allow its neighboring services to function while it gracefully bows out. However, monitoring microservices can help prevent the risk of a failure. For obvious reasons, this requirement adds more complexity to microservices as compared to monolithic systems architecture.

• Evolutionary

It’s an evolutionary design and, again, is ideal for evolutionary systems where you can’t fully anticipate what future devices will access your application. Many applications start based on monolithic architecture, but as several unforeseen requirements surfaced, can be slowly revamped to microservices that interact over an older monolithic architecture through APIs.

Microservices vs. monolithic architecture

A monolithic application is built as a single unified unit while a microservices architecture is a collection of smaller, independently deployable services. Which one is right for you? It depends on a number of factors. 

In 2009 Netflix faced growing pains. Its infrastructure couldn’t keep up with the demand for its rapidly growing video streaming services. The company decided to migrate its IT infrastructure from its private data centers to a public cloud and replace its monolithic architecture with a microservices architecture. The only problem was, the term “microservices” didn’t exist and the structure wasn’t well-known. 

Netflix became one of the first high-profile companies to successfully migrate from a monolith to a cloud-based microservices architecture. It won the 2015 JAX Special Jury award in part due to this new infrastructure that internalized DevOps. Today, Netflix has more than a thousand microservices that manage and support separate parts of the platform, while its engineers deploy code frequently, sometimes thousands of times each day. 

Netflix was an early pioneer in what has become increasingly common today: transitioning from a monolith architecture to a microservices architecture.

Challenges of monolithic architecture systems

Most organizations start with monolithic systems but generally start facing challenges when the business grows bigger. Some are listed below:

• As the application grows bigger, it becomes difficult to understand.
• Developers who start the programs and those who maintain them become different groups with the passage of time. Therefore, difficulty in understanding the application becomes more.
• Reuse of code is very limited only through shared libraries. This makes the coupling very tight.

However, microservices have the following advantages:

• Adding new people to the microservices team is a much easier job. Ne services can be handed over to new teams.
• Unused modules can be cleaned easily.
• The maintenance is also very easy with minimum downtime. The other microservices can continue to run undisturbed.

Examples of Microservices

Netflix has a widespread architecture that has evolved from monolithic to SOA. It receives more than one billion calls every day, from more than 800 different types of devices, to its streaming-video API. Each API call then prompts around five additional calls to the backend service.

Amazon has also migrated to microservices. They get countless calls from a variety of applications – including applications that manage the web service API as well as the website itself – which would have been simply impossible for their old, two-tiered architecture to handle.

Spotify, the music company, serves more than 170 million users worldwide. In order to be the world’s best music service, the organization wanted to make a few changes. Spotify designed a migration plan in 2015 and they split this activity into two parts: services and data. A team of engineers and Google experts first created a live visualization of the migration process to easily track progress.The team then mapped dependencies so that each of the microservices relies on 10 to 15 other microservices. The engineers then moved the systems in just a 2-week window, and during this period, they temporarily put on hold all the product development activity.

Uber started as a taxi-ailing app in San Francisco city. Here, a single monolithic codebase managed most of the requirements, such as business processes, billing, payments, and connecting with the driver. However, things became complicated when the business grew. Uber now covers more cities and is providing more services.

The Future of Microservice Architecture

We are living in a time when software production has been primed to perform. Coupled with intelligence and efficiency, the future of software development is still bright and is predicted to grow in the coming years. What matters not is the number of lines, but the rate at which software upgrades and updates find their way to you. Therefore, the future of software development is all about the speed of continuous integration. The two main architecture systems that are being used in building software are the monolithic and microservices architectures

Whether or not microservice architecture becomes the preferred style of developers in future, it’s clearly a potent idea that offers serious benefits for designing and implementing enterprise applications. Many developers and organizations, without ever using the name or even labeling their practice as SOA, have been using an approach toward leveraging APIs that could be classified as microservices.