Microservices

Microservices

For many years technology has become an integral and inevitable part of our lives, without which we cannot imagine surviving in this dynamic world. Today, from startups and small businesses to large-scale enterprises, everyone relies on innovation and technology to build an infrastructure and development process that is more flexible, offers maximum benefits, and helps them scale new heights of success. Whether it is the introduction of Cloud networking and DevOps for businesses' technical advancements or the invention of new, more prolific technologies, architectural patterns, and best practices, technology isn't still, but rapidly evolving to become more agile, scalable, and futuristic.

Microservices, a prominent architectural approach, is one such invention that has emerged from the world of scalable, domain-driven, continuous, and automated software development and delivery. Microservices have been making waves among forward-thinking software organizations in recent years and helping them become more agile and adopt a more collaborative corporate culture with DevOps.

So, let us further understand the significance of Microservices Architecture and unravel the role it plays in today’s technological sphere.

What are Microservices?

A trend that is rapidly taking over the IT industry, Microservices, also known as Microservices Architecture, is a variant of the Service Oriented Architecture (SOA) and an approach to building applications. Microservices are small, loosely coupled distributed services that allow software engineers to build new components of an application rapidly to cater to the changing business requirements.

The term was first coined in 2011 in a workshop of software artifacts and later introduced as an efficient solution to overcome the scalability and innovation challenges of traditional Monolith architecture.

Microservices Architecture became a distinctive method of developing software systems, which allowed development teams to take a large application and break it into its core functions or easily manageable small components called services, with narrowly defined responsibilities. Each of these services run their own processes and communicate with each other and other services through a well-defined interface, using lightweight mechanisms and protocols like HTTP-based API.

Powered by its fine-grained services and lightweight protocols, microservices architecture made application development, testing, deployment, optimization, and maintenance easier and allowed organizations to deliver large, complex applications rapidly, frequently, and reliably. Moreover, it offered organizations increased modularity and enabled them to evolve their technology stack. However, Microservices Architecture was not only focused on helping organizations evolve from monolithic architecture but also enabled them to restructure their development teams and inter-service communication for better handling of new feature integrations, inevitable failures, as well as future scalability.

In short, Microservices Architecture is the most suitable way for creating applications that are highly maintainable and testable, loosely coupled, independently deployable, organized around business capabilities, and owned by a small team.

Microservices Example:

Netflix, Amazon, Walmart, Uber, Twitter, and eBay are just a few examples of organizations that switched/evolved from monolithic or SOA to microservices architecture and consider it one of the reasons for the enormous success of their IT initiatives. These organizations successfully refactored their monolithic applications into microservices-based architectures, which helped them deliver services consistently, achieve scaling advantages, greater business agility, and unimaginable profits.

So, let us understand how Netflix used microservices to tackle the challenges they were facing.

Netflix began its Microservices journey in 2008 before the approach was even established. The company was suffering from service outages, scaling challenges, and was unable to deliver DVDs to customers, which led them to gradually refactor their monolithic architecture application, service by service, into microservices. This helped them overcome these challenges as well as enjoy cost reduction.

Hence, with Microservices the company API gateway was handling two billion daily API edge requests, managed by over 500 cloud-hosted microservice by 2015, whereas by 2017, its architecture consisted of over 700 loosely coupled microservices.

Characteristics of Microservices Architecture:

Microservices Architecture has become a game-changer in the field of software development because of its ability to fix arising problems and failures in isolation to make sure they do not impact or break the rest of the application functions. Today, enterprises like Netflix, Amazon, Walmart, and Twitter are leveraging this tech for various functions like handling high loads, implementing complex systems, ensuring system stability, etc.

But, that’s not all.

Various other characteristics make this application architecture style the most suitable one for success-oriented organizations, such as:

• Multiple Components: As stated earlier, the microservices architecture allows teams to break an application into multiple components services so that they can be deployed, tweaked, and then redeployed independently without compromising its integrity. Hence, a change, issue, or failure in one or more distinct services does not impact the entire application.
• Simple Routing: Microservices Architecture follows smart endpoints and dumb pipes approach for building communication structures between different processes, which is somewhat similar to the classical Unix system. In short, applications built from microservices architecture receive requests, process them, and generate a response accordingly, unlike Enterprise Service Buses (ESBs) that use sophisticated facilities for message routing, choreography, transformation, and applying business rules.
• Built for Business: One of the most prominent characteristics of Microservices is that it is built around business capabilities and priorities. It can use different technology for various purposes based on business requirements.
• Decentralized: It favors both decentralized governance and data management.
• Evolutionary: Microservices architecture is an evolutionary design that is used for building evolutionary systems. It allows teams to make frequent, fast, and well-controlled changes to software, without affecting its functionality, making it suitable for future requirements, interactions and revamps.
• Failure Resistant: Another characteristic that makes microservices popular is that it is designed to cope with failure. It removes a single point of failure and ensures that any issue in one service does not affect the entire/other parts of the application, allowing it to function consistently.

Microservices and DevOps:

Microservices emerged from DevOps ideologies that were first introduced at organizations like Amazon, Netflix, SoundCloud, Facebook, Google, etc. Both DevOps and Microservices are two interconnected approaches to software development that follow a similar concept of leveraging small teams to create functional changes to the organizations’ services, one step at a time. Together they are an ideal method for increasing the throughput of teams and the overall quality of services.

Today, the rapid adoption of agile methodologies fueled DevOps teams to use microservices to extend application functionality, without affecting its other parts. It has further become an integral aspect of DevOps practices Continuous Integration and Continuous Delivery, where it is used to achieve frequent software deployment and releases, to make new services and updates immediately operational on any system or device.

Other prominent advantages offered by Microservices to DevOps teams include:

• Deployability: Microservices' shorter build, test, and deployment cycles help increase agility and allows the release of new versions of a service.
• Productivity: Uses a common toolset for both development and operations, which further brings productivity to DevOps. It helps establish common processes for requirements, dependencies, and problems, which facilitates collaboration and allows the team to successfully resolve issues.
• Availability: Helps increase application availability by releasing a new version of a particular microservice or application function with very little downtime.
• Scalability: It can be scaled independently using pools, clusters, and grids.
• Modifiability: It loosely coupled, modular components make it flexible, easier to work with, supports dynamic discovery, etc.

Benefits of Microservices Architecture:

Microservices architecture is a domain-driven design methodology that helps organizations build flexible applications. Moreover, this modular and encapsulated design approach allows rapid and continuous changes and improvements and adheres to principles like fine-grained interfaces and business-driven development.

Hence, the advantages of following microservices architecture are multifold, a few of which are:

• Improved scalability: In microservices, each service is a separate component, which allows the team to scale up a single function without impacting the entire application. This improves scalability and enables businesses to deploy business-critical services on multiple servers for increased availability and performance.
• Faster time to market: Since microservices work with loosely coupled services, it has shorter development cycles and agile deployment, which helps teams to develop and deliver independently testable and deployable to the customers faster.
• Easier debugging and maintenance: Microservices architecture applications are built-in smaller modules and go through continuous delivery and testing processes, which makes it easier for the team to debug and maintain them.
• Easy to deploy: Microservices app’s modular and encapsulated design makes it easy to deploy.
• Accessible: It is easy to understand, update, and enhance a microservices app, as it is broken into smaller components for development. This results in faster development cycles, which makes the application quickly accessible to the end-user.
• Resilient: Microservices apps are more resilient, as each of their components is built independently and does not impact one another if one of them fails.
• More open: Microservices architecture offers great flexibility to developers to choose the best language and technology, as per the function and business requirement.
• Easier Process Adoption: Microservices makes it easy to adopt new technology and processes for organizations, helping them update their tech stack.
• Independent scaling: Each component or microservice of an application is scaled independently through cloning and sharding.
• Improved ROI: Microservices helps organizations to optimize resources, create reusable code, reduce development time, deploy more quickly, reduce infrastructure cost, and minimize downtime all of which play an integral role in improving ROI.

Microservices Challenges:

Microservices though came as a more beneficial and efficient solution to the challenges of monolithic architecture, it does have certain limitations and challenges, which make developers a little apprehensive about its implementation. These challenges are listed below:

• Configuration Management: With a microservices architecture, teams need to maintain configurations for hundreds of components across environments, which is extremely challenging to manage.
• Automation: Since there are several smaller components here, everything needs to be automated, which becomes challenging.
• Testing: Testing of Microservices architecture apps can be difficult, as it requires excessive efforts for integration and end-to-end testing and to ensure all the dependent services are up and running.
• Debugging: It is extremely challenging to track down service failures in Microservices, as the team needs to check multiple services across different components.

Microservices Best Practices:

To achieve maximum benefits with any process, development teams need to implement effective strategies, adopt the latest technologies, as well as to follow the best practices. Though the former two aspects vary based on project and business requirements, there are certain best practices of a process that are followed universally and beneficial to all.

Therefore, here are several best practices for creating an application with a microservices architecture.

• Planning & Organizing Stage:
  1. Ensure Microservices Architecture is a good fit as per your requirements. This will help you ensure whether your application can retain its core features and operability when sub-divided into microservices.
  2. Get everyone on board and build teams around microservices.

• Designing Stage:
  1. Differentiate your microservices from business functions and services to avoid building too large or small microservices.
  2. Make sure your servers are loosely coupled, have cohesion, and cover a single bounded context to achieve a Domain-Driven Design (DDD).
  3. Use APIs and events for communicating between services.
  4. Use models like DevSecOps to create a secured microservices framework.

• Microservices Development Stage:
  1. Version your microservices for breaking changes.
  2. Include backward compatibility for the service endpoints you are exposing.
  3. Also, ensure the API changes are also backward compatible.
  4. Use a separate version control strategy for each service.
  5. Make sure your development environment is consistent across machines.

• Data Storage and Management:
  1. Use different databases or data stores for each microservice, as it will help you create a robust microservice framework that maintains each service independently and works in cohesion with other services through a service mesh.

• Deployment & Hosting Stage:
  1. Deploy your microservices separately to a dedicated infrastructure hosting to save time, integrate fault tolerance, and avoid outages.
  2. Automate the deployment process.
  3. Containerized microservices to independently deploy and manage individual services, without affecting services hosted on other containers, and enjoy platform-independence and interoperability.

• Maintenance & Operations Stage:
  1. Use a centralized logging and monitoring system for faster error handling and root cause analysis.
  2. Use an advanced monitoring solution for monitoring resource-availability and maintaining security by identifying compromised resources early.

Microservices Vs. Monolithic Architecture Vs. SOA:

Since Microservices have evolved from Monolithic and Server Oriented Architecture (SOA), a comparison between them is inevitable. This will help us better understand the significance of Microservices architecture and highlight the reasons it has become the most sort after application designing approach.

Points of Difference	Monolithic Architecture	Server Oriented Architecture	Microservices Architecture
Design	Designs a single logical executable or service, containing all the required functionalities.	Designs services of various sizes and ranges, like single-feature applications, full-feature products, or sub-systems.	Designs one service to complete one task successfully.
Flexibility	A systematic change leads to complete redeployment of the application.	A systematic change in SOA requires modifying the monolith.	Whereas, here a system change is for creating a new service.
Communication	Uses method invocation or function call for communication between components.	Uses Enterprise Service Bus (ESB) and messaging protocols such as AMQP, MSMQ, SOAP, etc. for communication.	Uses homogenous and lightweight protocols like HTTP, REST, and simple messaging systems (JMS, MSMQ) for communication.
Component Sharing	It has a shared database, which allows component sharing between	Allows component sharing between different components of the application.	Relies on bounded context to minimize component sharing between application components.
DevOps & CD	Does not incorporate DevOps or CD, as it has a limited number of technologies.	SOA incorporates DevOps and CD occasionally as per business requirements.	There is a strong focus on DevOps & CD.
Containers	As Monolithic Architecture is tightly coupled, it does not use containers.	SOA rarely uses containers for development.	Relies on containers to be self-sustaining and self-running.
Data Storage	It uses a single logical database for persistent data storage.	Data storage is shared between services.	Uses independent data storage for each service.

Conclusion:

Microservices have become an important software trend, with profound implications on organizations’ IT functions and digital transformation. However, it is crucial to understand that this popularity of Microservices does not mean the end of Monolithic or Server Oriented architecture. Organizations must carefully consider what architecture makes the most sense and opt for the one most suitable to their business requirements, as any approach can only be rewarding if it effectively caters to their needs and customers’ demand.