Most Asked Microservice Interview Questions For 2024

To keep up with changing trends in the tech industry where speed, flexibility, and scalability are crucial, web and mobile application developers globally are using microservices architecture for improved user experiences, simple operations, and better productivity.

It offers the ability to quickly respond to changes, help developers build new features, and deliver applications that are fast, responsive, and highly integrated within an ecosystem. Microservices architecture is becoming more popular because it provides the ability to enhance scalability, flexibility, and maintainability in developing large-scale modern applications.

But despite offering new opportunities, microservice architecture often exposes unique challenges for testing teams in delivering features and changes frequently. To overcome this challenge they opt for test automation as it provides better accuracy, faster results, and greater operational efficiency.

Leveraging automation in testing microservices helps developers and testers perform complex testing tasks more accurately. Automation also helps in improving both the depth and scope of microservices testing, resulting in better test quality and coverage. Furthermore, using automation testing microservices, testers can quickly and easily simulate many users, so that they have a quality experience while interacting with the application.

The increasing popularity of microservices architecture has led to the demand for skilled microservices developers and architects. In this article, we will provide a comprehensive list of commonly asked microservices interview questions to help you start a career as a microservices developer or hire a team of outstanding microservices developers for an organization.

These interview questions will provide you with in-depth knowledge of microservices architecture to upskill and advance in your career and identify your goal. 

Most Asked Microservice Interview Questions

What is meant by Microservices?

Microservices or microservices architecture are architectural styles that structure an application into small autonomous services or functional modules that can be developed, deployed and maintained independently. It starts with a small section that builds a large structure that holds a particular section together.  Each service in a microservice architecture is independently focused on a specific business capability but correlated with the other service through well-defined APIs. So, if damage happens to one it does not impact the whole structure. 

In addition to helping in easy maintenance, this architecture also makes development faster. In addition, microservices are a big asset for the latest software development methods as they make development faster by delivering large, complex applications quickly, frequently, and reliably.

What are the benefits of employing microservices

Some of the main benefits of Microservices include:

• Microservices facilitate faster development cycles and easy integration with new technologies, libraries, databases, and frameworks, allowing developers to swiftly add new features and then simply change or remove them at any moment depending on changing market demands.
• Components are generally disconnected inside a system. As a result, the specific components of the application may be simply built, modified, and scaled independently.
• Offers developers the option of selecting the appropriate tools to tackle their issues.
• Seamlessly align with DevOps principles, fostering collaboration between development and operations teams for continuous delivery by automating the development, and testing, of applications.
• Isolation between microservices simplifies troubleshooting and updates, reducing downtime and minimizing the risk of system-wide failures, which ensures that failures in one component do not affect the entire application. This as a result enhances fault tolerance  and system resilience

Tell any two challenges faced while using Microservices

developers face a few challenges while using Microservices they are:

• As microservices rely on each other, there is a need for communication with one another.
• Using Microservice architecture comes with operational overhead because it requires heavy investment and architecture setup.

What are the essential components of microservices?

Microservices consist of-

• API Gateway through which microservices communicate with each other
• Message brokers to facilitate passing messages between microservices 
• Service discovery mechanism to discover each microservices dynamically in a changing environment.
• Event streaming for real-time data processing and stream events between microservices.
• Containers, Clustering, and Orchestration
• IaC [Infrastructure as Code Conception]
• Cloud Infrastructure

Explain the term monolithic architecture

Monolithic architecture is a traditional way of creating applications. In this architecture, all the components of an application are tightly packed together in a large container. Typically, these applications are created as a single interconnected unit with a single code base. All the components that are tightly integrated, make it challenging to independently scale and modify individual parts.

What are a few challenges of shifting from a monolithic architecture to microservices?

Shifting from a monolithic architecture to microservices can be challenging because of the following reasons.

• It requires careful analysis and planning to identify the appropriate service boundaries and break down a monolith into cohesive microservices.
• Data management poses another challenge in a distributed environment, since transactions may span multiple microservices making it more complex to handle data.
• Ensuring efficient and reliable communication between microservices is crucial to avoid performance bottlenecks and failure flow hence inter-service communication is another challenge.
• Requires robust DevOps practices because managing multiple services, monitoring, and logging can increase operational complexity
• Ensuring consistency across microservices during data updates is also challenging.

Why are reports and dashboards used in Microservices?

Reports and dashboards are used to monitor and upkeep services. They find out which microservices expose what resources, and services are impacted when changes in components occur, which version of the components are deployed, and a sense of compliance and maturity from the components. 

What is an API gateway? 

An API gateway in microservices acts as a main entry point to handle client requests and then routes them to the appropriate microservices. It allows clients to access microservices without needing to know microservice implementations.

Explain why to use API gateway in microservices

API gateway serves several purposes:

• API gateway helps in combining multiple backend microservices responses into a single response to fulfill a client request.
• For optimal resource utilization and high availability, the gateway can distribute incoming requests across multiple instances of the same microservice.
• Handles security-related issues by authenticating and authorizing access to clients to specific microservices.
• The API gateway improves performance and reduces redundant requests and caching responses from microservices. 
• Translates client requests from one protocol to the appropriate protocol used by the underlying microservices.

What is meant by containers in microservices and why is it useful?

Technologies for allocating and sharing resources have containers. Containers are packages of microservice-based applications that contain all the necessary elements required to run in any environment. Containers allow the packaging of each microservice and all of its dependencies into a standard format called container image. Each microservice deploys into its container to instantly release new instances of the microservice.

Describe the main testing types used in microservices.

Microservice testing becomes fairly complex to perform because several microservices interact with one another. Therefore, tests are grouped according to their level of difficulty:

• The first test is the bottom-level technology-related tests, such as unit tests and performance tests.
• Tests at the middle level are exploratory tests, like stress tests and usability tests.
• Tests at the top level are acceptance tests. The acceptance tests aid developers in comprehending and confirming the characteristics of the application.

This entire testing process is automated.

Explain the role of service registration and discovery in a microservices environment

Since microservices are distributed across physical hardware nodes, developers must be able to find the location of any microservice. Service registration and discovery play a vital role in facilitating dynamic communication between microservices.

When a microservice starts up, it registers itself with a service registry that provides essential information like its network location, API endpoints, and health status. A service discovery is a registry of names with the actual location of the microservice. When one microservice needs to communicate with another, it queries the service registry to discover the network location and endpoint details of the target service.

Tell the name of some leading companies utilizing microservice architecture.

Several famous companies have adopted microservices architecture to build their applications and enhance their services. Some of them are:

Netflix- A well-known entertainment streaming platform relies heavily on Microservices architecture to deliver its streaming services worldwide, using multiple individual microservices to handle its different aspects, such as user authentication, content recommendation, and video streaming.

Amazon- It utilizes a microservices approach for various services of its platform, including Amazon Prime, AWS, and other Amazon retail functionalities.

Uber- It uses a microservices architecture to manage its complex task of coordinating millions of rides daily to ensure reliability and scalability.

Twitter- Twitter also has shifted to a microservices architecture to efficiently handle its millions of users, tweets, and real-time interactions.

Spotify- It utilizes microservices to manage its seamless music recommendations, user preferences, and personalized playlists.

Google- Uses microservices for various products and services, including search, Gmail, and maps.

LinkedIn- A professional networking platform that employs microservices architecture to manage user profiles, job listings, and networking features.

eBay- An online marketplace place has also adopted Microservices architecture to handle its vast product catalog, user accounts, and payment processing.

PayPal- A digital payment platform that uses microservices to manage transactions, user accounts, and security features.

Airbnb- An online hospitality service that utilizes microservices on its global platform to handle booking, payment processing, search functionality, and user reviews

Name a few tools used in building microservice architectures

There are countless tools available for Microservices, but the most common are-

• Docker- A container framework, used by the developers, to deploy microservices and their dependencies into containers. It helps set up apps in lightweight, portable containers in an automated way.
• Kubernetes- An orchestration framework used to manage, scale, and automate Docker containers
• Spring Boot- Provides a rapid development framework used to build, test, and launch microservices.
• LambdaTest- An AI-powered test orchestration and test management platform to improve both the speed and accuracy of testing microservices applications and their dependencies efficiently.

Utilizing LambdaTest for testing microservices architecture

For efficient microservices testing, each application needs to undergo a series of tests, including, unit testing, contract testing, service testing, API testing, Integration testing, end-to-end testing, functional testing, and others. While automating unit and functional tests is easy, automation of other tests is not, because of dependencies.

Therefore for automating microservices testing, it is essential to utilize a robust test automation platform like LambdaTest. LambdaTest is an AI-powered test orchestration and execution platform that helps streamline the test creation and execution process. It enables developers to run manual and automated microservices testing at scale. 

Additionally, the platform allows performing real-time and automation testing of both web and mobile across more than 3000 environments, real mobile devices, and browsers.

By leveraging LambdaTest Al, test maintenance becomes easier. It helps developers test complex microservices applications and their dependencies quickly and efficiently with reduced time, effort, and cost. This facilitates faster releases while improving test accuracy and coverage.

LambdaTest allows developers to perform advanced data analysis via modern modeling techniques. They can also detect and correct bottlenecks in the deployment pipeline. Meanwhile, carry out detailed root-cause analysis to improve the testing process.

Conclusion

It can be concluded that understanding the microservices architecture’s fundamental concepts and difficulties is essential to adapt to changing innovations in microservices architecture.

Above, we have discussed the top microservices interview questions that can help aspirants advance their careers as microservices developers and build their applications and for hiring managers to open up new opportunities for their organization.