What is Microservices Architecture?

Organizations today are running increasingly strategic application workloads in the cloud to benefit from efficiencies in cost, scale, agility and the ubiquity of reliable cloud hosting services. Microservices-based architecture is the key driver of this trend, and is fast becoming the prime choice for building new applications that scale efficiently and support agile development practices.

Microservices architecture takes a single application and breaks down its functional components into a series of loosely coupled tiny applications that talk and coordinate with each other, usually over a network. This means near 100% perceived uptime for users with a much better user experience, while for enterprises it means reduced costs. Leading brands like Amazon, Netflix, and eBay have been using microservices to launch functions like shopping cart, credit card processing, and search. Using microservices, many businesses can overcome the problems and delays that are faced with traditional, monolithic application development and management. Let’s look at Microservices in detail.

Simply put, imagine an app that is a composite of several independent functional systems working together. Microservices are small self-contained apps that can be built, deployed, and managed independently, using modern, cloud-native processes and technologies to automate the provisioning and operating of these services. Microservices are also called Microservice architecture and are a method of designing software systems that create an application as a bunch of loosely joined services.

The key reason Microservices were developed is that certain applications become easier to build and maintain when they are broken down into several smaller components that work together. Each component can be easily and completely decoupled from each other, allowing developers to run their own process and communicate autonomously without having to rely on other teams.

The monolithic architecture pattern is the traditional architectural style that is largely prevalent. A monolithic application built as a single, autonomous unit. This structure is based around the concept of a single, indivisible unit, including the server side, client side, and the database. While this style has been an integral part of many businesses, its numerous limitations and issues are motivating more and more to make the switch to Microservices. Monolithic applications are hard to change and it takes a long time. As monolithic applications scale, they can become quite complex, so the overall development is generally longer. Moreover, each change implemented can impact the entire system, requiring an entire rebuilt and deployed version of software, even if it is a modification just to a small section of code. If developers want to enhance particular features and functions of an application, they have to scale the entire application making the process complex.

Microservices on the other hand allow developers to take a simpler, faster approach towards managing applications by breaking down the monolithic unit into independent ones that function as separate services that communicate with each other through APIs. Every service has its own logic and codebase. However, building an application as a microservice from ground up takes longer time, so it would be best to build the application as a monolith and then move towards a microservice approach. That’s because as the monolithic application matures the functions that should be split out into microservices will be more obvious.

The answer is simple – manageability. When applications, or software, are built as a composite of independent, modular components they become easier to manage, maintain and test. They help enterprises be more agile and improve the quality of their workflows and while reducing the time required to improve features or enhance production. As long as the dependencies between microservices are managed appropriately, changes can easily be made to optimize team needs and performance. Microservices have already proven themselves as being a superior system than monolithic applications, especially when it comes to large enterprise applications that are typically developed by distributed and diverse teams.

Developer Independence 

When it comes to developing applications based on microservices architecture, developers find it easier because it allows much more developer independence than traditional systems. Small developer teams are able to work in parallel and are more agile which makes it easier to iterate faster than large development teams. They can also scale the services on their own without having to wait for a larger and more complex team.

Higher Resilience  

A big advantage of microservices is the quality of isolation and resilience. In microservices architecture, even if just one of the components fails due to any issue, such as the technology becoming outdated or the code involved being such that it can’t be developed any further, developers can create a whole new component on the side without any interruptions. This means that the rest of the application continues to function independently. Developers thus have the freedom to develop and deploy services as needed without having to wait on decisions concerning the entire application.

Easy to Scale  

Due to the fact that microservices are made of much smaller components as compared to monolithic software, they utilize fewer resources and are therefore easier to scale in order to meet the growing demand. And this can be as specific as scaling just a single component of the application. As a result of this isolation feature, microservices can properly function even during large changes in size and volume, making it an ideal method for enterprises dealing with a wide range of platforms and devices.

Developed Autonomously    

Compared to monolith applications, individual components are easier to fit into continuous delivery pipelines and complex deployment scenarios. That’s because developers are able to work solely on the specified service that needs to be altered or improved and redeployed when a change is needed, without impacting other components, which can continue to function independently. In addition to the obvious benefits this offers the system, this autonomous nature is also beneficial to the team because they can perform scaling and development without requiring much coordination with other teams. This is a huge advantage for companies that are more distributed and workers are located remotely. Technical decisions can be made quickly that integrate with other services in a flash. Cross-functionality has never been easier.

Better for Business  

Microservice architectures are designed to align with different business domain boundaries, organized around capabilities such as logistics, billing, etc. This increases independence and understanding across the organization as different teams are able to utilize a specific product and then own and maintain it for its lifetime.

Evolutionary

A very important benefit of microservices architecture is that it is highly evolutionary. In any business enterprise it is likely that there will be newer requirements. Microservices are an excellent option for such scenarios where developers can’t fully predict what devices will be accessed by the application in the future, and they allow quick and controlled changes to the software without slowing the application as a whole.

Improves Productivity 

Complex projects require large development teams that need to work together. With microservices, application development projects can be divided into smaller, independent units. This means that teams can act independently regarding domain logic, which minimizes the coordination and effort. On top of that, the teams responsible for each microservice can make their own technology decisions depending on their needs.

Integrates Easily with Legacy Systems  

Monolithic systems are not very easy to maintain, mostly because legacy systems can be poorly structured, poorly tested, and/ or dependent upon outdated technologies. In contrast, microservices can work alongside legacy systems to improve the code and replace old parts of the system. Integration is easy and can solve many of the problems that come with monolithic systems.

While many enterprises are reconfiguring their monolithic in favor of a microservices approach, microservices may not necessarily be the right answer in all scenarios. It comes with its own set of challenges. Microservices architecture may not be the only perfect way to design an application. Here are some of the challenges associated to microservices:

Related Complexity

A monolithic system’s complexity comes from how challenging it can be to understand how different code interacts. On the other hand, microservices architecture’s complexity results from having a lot of the code split out into individual services. The higher the number of services involved, the more complex it gets.

Microservices Can Be Expensive

Network calls made by APIs aren’t free and the cost can add up to something huge. In addition, the cost of developer effort involved in breaking up a monolith can create an otherwise unnecessary expense.

Security Risks

Each inter-network communication path creates a new security risk that needs to be addressed and monitored.

Microservices Require More Work

The operation of a microservices architecture-based system usually requires more effort by a developer because there are more deployable units, and each of these need to be deployed, managed and monitored. Changes to interfaces must be implemented so that an independent deployment of individual microservices is still possible.

Testing Can Be Complicated

Since all microservices have to be tested together, one microservice can block the test stage and prevent the deployment of the other microservices. There are more services or interfaces to test, and testing has to be independent for both sides of the interface.

Changing Multiple Services is Difficult

Changes that affect multiple microservices can be more difficult to implement. In a microservice system, changes require coordinated developer effort.

Microservices has been gaining a lot of traction in the development community. One key reason behind this is because microservices architecture addresses problems that modern enterprises often face, such as responding to market demands, handling spikes in traffic, and being resilient in times of failure, and so on. Microservices aid agility by allowing developer teams to focus on a narrower domain, increasing scalability by giving smaller units of scale so additional instances of a service can be whipped up to cater to growing demand. They also help enhance fault tolerance providing isolation units that can contain the scope of faults.

The beginning of Microservices lies originally with web companies that wanted to be able to manage millions of users with high variance in traffic as well as changing market demands, without affecting the performance of the website in any way. These companies pioneered various approaches to achieve this, such as technologies, design patterns, and operational platforms etc., and these were shared with the open source community to help other organizations to adopt Microservices.

As of now there is no defined formal standard for microservices architecture, but there are several common characteristics that define a Microservices architecture. Some of these are independently deployable services, automated deployment, intelligence in the endpoints, and decentralized control of languages and data.

• Maintain a limited and focused business scope for each specified microservice in order to meet the agility in development and delivery of services. This is referred to as the single responsibility principle.
• During the design/ development phase, developers need to discover and define the boundaries of the microservices and align them with business capabilities. This best practice is also known as bounded context in domain-driven design.
• Developers need to make sure that the designed of microservices matches the agile/independent development and deployment requirements of the application. The development team should focus on the scope of the microservice, instead of considering reducing the size of the service.
• Another best practice is to start with somewhat broad service boundaries initially, and at a later stage in the development process allow business requirements to refactor the smaller ones.

To begin with, developers can relax because a very solid benefit of microservices architecture is that developers are not required to move away entirely from a monolithic system all in one go. Microservices can be transitioned to gradually. That’s why most IT environments in organizations deploy a mix of both microservices and monolithic applications. With this in mind, let’s look at the key steps involved in moving to a microservices approach.

Agile Application Development

In most situations, the transition to microservices is driven by the move from a waterfall approach to agile applications development. Adopting and learning agile methodologies is therefore a very important first step. The shift also means reorganizing teams around the specific microservice they are being designed to support.

Audit Existing Applications

Another critical step is evaluating individual monolithic applications to see which existing features or components of those apps can be separated into their own microservice. A good idea is to start with such features and begin a migration path to microservices, instead of performing a ground-up rewriting of all existing applications. Evaluate between re-use vs re-write and make the smarter, more efficient choice. This stage is also an appropriate time to assess which applications are no longer useful to the company’s workflow.

Establish Mandates to Govern Application Development

Now that you have decided to transition to a microservices architecture, it is time to put in place defining policies that will mandate various aspects of microservices-based application development. While a full list will be longer, some of the vital points are:

• All new applications must be built based on an agile approach and microservices pattern
• All new features to be added to existing monoliths will be developed as separate services or follow a microservice pattern rather than simply adding it to the existing monolithic application code or current architecture
• Development teams have to lay the groundwork for cloud providers, platforms and tools that will be used to avoid uncontrolled adoption of a multitude of tools and technologies which could run into hundreds

Synchronize IT Infrastructure and Development

Create a foundational platform that links your IT infrastructure to your development platforms, process, and tools automatically. The platform should be able to offer the developer team all the resources and serverless functionality they need to rapidly build and maintain applications. It should also be able to integrate existing infrastructure with a public cloud and SaaS services into your enterprise, while maintaining security, management, and networking requirements specific to your business.

Many IT teams are still unsure about microservices architecture, which to be honest is very new compared to monolithic structures that have been governing software/ application development for decades. Their reticence towards this transition is thus natural because change is always difficult. But migrating to an application-led IT architecture to support the growing adoption of microservices will continue and traditional systems engineers will need to evolve along with the transition.

To make the adoption of this new change easier, development teams must understand business requirements and leverage the knowledge and expertise of their technology partners. This will help them develop an understanding of the key components of the microservices architecture, learn what is needed to make the switch, and determine how the IT team can most effectively adapt to the new infrastructure reality.

• Software Testing

• Software Security Testing

• Automated Testing

• Functional Testing

• Agile Testing

• DevOps Testing

• API Testing

• Microservices Architecture