What Everything You Need to Know About Microservices

Just like technology, architectural style is a crucial concern in software development. This is why understanding different architectural patterns is important. While it may not be possible to cover all patterns in a single article, the focus of this particular article will be on microservices.

In this article, we will discuss what microservices are and the key differences between monolithic and microservices architectures. We will also discuss the benefits and disadvantages associated with Microservices.

By the end of this article, you will better understand microservices architecture and its benefits. You will also be able to decide whether microservices architecture is the right choice for your next project.

Monolithic vs. Microservices

What does mean by a monolithic architecture?

To understand Microservices fully, we need first to understand monolithic structures. It is more traditional architecture. Monolithic architecture is a time-tested approach that involves building everything as one big application.

In other words, it is the simplest and most traditional type of architecture. In this architectural style, all of the code for the application is contained in a single unit. This makes it easy to develop and deploy the application.

What is Microservices?

Microservices, on the other hand, are individual, self-contained services that can be deployed and scaled independently that involve breaking down an application into a bunch of smaller, independent services.

They are a bunch of smaller, independent services that work together. This makes it much easier to scale your app because you can just scale the services that need to be scaled. They communicate via well-defined APIs. This makes them well-suited for applications that need to be scalable and adaptable.

Why Microservice?

For small business owners, it can be a pain to scale if your app has monolithic architecture.

When you approach a company for application development, they will likely ask you about the architectural style you want to use. This is an important decision, as it can have a significant impact on the development cost and scalability of your application.

Monolithic architectures are simpler to develop and maintain, but they can be difficult to scale. If one part of the application becomes overloaded, it can affect the entire application. Microservices architectures are more complex to develop, but they are more scalable. If one service becomes overloaded, it will not affect the other services.

Here is an example to help you understand the difference between monolithic and microservice architectures.

Imagine you have a social media app that has user management, posting, commenting, and liking features. If one service, say user management, gets a lot of traffic, it will use more resources and affect the other services. This is because all the services are tightly coupled together.

To fix this, you would need to scale the entire application, which can be time-consuming and expensive.

A better approach is to break the services down into microservices. This means that each service will be responsible for a specific task, such as user management, posting, or commenting.

This makes the services loosely coupled, which means that if one service gets overloaded, the others will not be affected. This makes it much easier to scale the application because you can simply scale the individual services that need it, not the entire application.

Characteristics of Microservices

One of the key characteristics of microservices is their focus on modularity, meaning each service handles a specific function or capability. Additionally, microservices are designed to be loosely coupled, meaning they can be developed, deployed, and scaled independently, without affecting other parts of the system. 

Autonomy

Microservices exhibit loose coupling, enabling independent deployment, development, and scalability. This facilitates the effective management and maintenance of microservice-based applications.

Componentization

A prevailing approach involves dividing a system into smaller components. This permits individual focus on specific services or components, enabling independent modification and deployment without compromising the overall integrity of the application.

Specialization

Each service is designed to address a specific problem or provide a distinct set of capabilities. If a service becomes overly complex, it can be further broken down into smaller, more specialized services.

Benefits of Microservices

1. Agility

Microservices promote agility by dividing project work into small, independent teams. This approach allows each team to focus on a specific aspect of the application without affecting the other teams. This results in more efficient and faster work, as each team can work independently and focus on their own tasks.

Although working together can also be productive, having independent teams working simultaneously can reduce the development cycle. This is because each team can work on their own tasks without having to wait for the other teams to finish their work. This allows us to develop more customer-ready applications in less time.

2. Flexible Scaling

E-commerce platforms and other service-based applications often require frequent scaling of their systems. However, smaller companies may find it costly and labor-intensive to allocate more resources and scale the entire application. In contrast, microservices have gained popularity because they offer flexible scalability. This is why tech giants like Amazon, Netflix, eBay, and others have adopted microservices to achieve flexible scaling.

3. Easy Deployment

Loose coupling of services also promotes the easy deployment of applications by enabling the deployment of specific services that have undergone continuous improvements. This eliminates the need for developers to extensively rework the entire codebase. As a result, businesses can effortlessly include new features as required without significant effort.

4. Technological Freedom

In a microservices architecture, teams can choose the tools and technologies that work best for them. This means that they can use the latest tools, or they can stick with tried-and-true solutions. They can also use a mix of different tools, depending on the specific needs of each microservice.

For example, you start building a microservice that requires storing a lot of data. You could use a traditional relational database, but this might not be the best choice. Relational databases are not designed for high-performance storage, so you might end up with a slow and inefficient microservice.

Instead, you could use a NoSQL database, which is specifically designed for high-performance storage. NoSQL databases are more flexible than relational databases, so you can choose the right data model for your needs. This will lead to a faster and more efficient microservice.

The flexibility of microservices architecture allows you to mix the best tools and technologies for the job.

5. Reusable Code

Imagine you have a big piece of software that does many different things. Instead of having all the code in one huge chunk, you divide it into smaller, well-defined parts called modules.

These modules are like building blocks that have specific functions. For example, one module might handle user authentication; another module might handle database operations, and so on. Each module can be used independently to perform its specific task.

Now, the good thing is that these modules can be reused in different parts of the software. So, if you have a module that handles user authentication, you can use it not only in one part of the software but also in other parts that require user authentication. This saves time and effort because you don't have to write the same code multiple times.

Similarly, in a microservices structure, you can reuse services if the same functionality is needed in different parts of the software. This promotes efficiency by avoiding redundant code and allowing the same service to be utilized in multiple areas as needed.

6. Resilience

With microservices, applications are divided into smaller, independent services that work together. If a single microservice doesn’t work, it doesn't bring down the entire application. Instead, the application gracefully degrades its functionality, meaning it can still continue operating to some extent without crashing completely.

Why Spring for Microservices

Microservices can be developed using various programming languages and technologies. However, one of the most widely used frameworks for building microservices is Spring Boot using Java/Kotlin. Spring Boot has gained popularity for various good reasons.

• Building microservices using SpringBoot is effortless and fast.
• Spring Cloud provides tools for devs to build some of the common patterns in microservices in no time.
• It comes with production-ready features like metrics, security, and embedded servers. 
• The Spring community is massive. If you ever get stuck, there are plenty of Spring developers out there to help you out.

Challenges With Microservice Architectures

Microservices are not all sunshine. Though they are great for scalability and flexibility, they also come with a few challenges. Let's take a look at some of the inherent complexities of microservices architectures.

Automating the Components

The number of smaller components in a microservices architecture can make it difficult to automate everything. This includes builds, deployments, and monitoring. It is important to have a solid automation strategy in place to ensure that all of the components are managed effectively.

Perceptibility

The distributed nature of microservices can make it difficult to monitor and identify problems. It is important to have good visibility into all of the components in order to troubleshoot issues quickly. Centralized logging and dashboards can help to improve perceptibility.

Configuration Management

The configuration of microservices can be complex and difficult to manage. It is important to have a centralized configuration management system in place to ensure that all of the components are configured consistently. This will help to avoid errors and inconsistencies.

Debugging

Debugging microservices can be challenging because there are so many moving parts. It is important to have a good understanding of the architecture and how the components interact. Centralized logging and dashboards can also help with debugging.

Consistency

It is important to have some consistency in the way that microservices are implemented, deployed, and monitored. This will help to avoid chaos and make it easier to manage the architecture. However, it is also important to allow for some innovation and flexibility.

Microservices Example

A social media platform like Facebook or Twitter are a prime example of microservices. In this scenario, various microservices handle different features such as user authentication, posting updates, sending messages, managing friend connections, and generating news feeds. Each of these services operates independently, with its own database and codebase, allowing for seamless scalability and fault isolation.

For instance, if the messaging service experiences a surge in traffic, it can be scaled up independently without affecting other services. Similarly, if there's a bug in the authentication service, it can be fixed and redeployed without impacting the rest of the platform. This modular approach not only enhances scalability and fault tolerance but also facilitates continuous delivery and faster time-to-market for new features and updates.

Best Practices for Microservices

Microservices practices refer to the set of principles, methodologies, and techniques used to design, develop, deploy, and maintain microservices-based architectures effectively. These practices encompass various aspects of software development, including architecture design, communication protocols, deployment strategies, monitoring, and organizational culture.

1. Decomposition: Breaking down the application into smaller, loosely-coupled services that each handle a specific business function or capability.

2. Service Independence: Ensuring that each microservice operates independently, with its own data store and minimal dependencies on other services.

3. API First Approach: Designing APIs to facilitate communication between microservices, often using RESTful or event-driven patterns.

4. Containerization: Packaging microservices into lightweight, portable containers (e.g., Docker) for consistent deployment across different environments.

5. Orchestration: Using orchestration tools like Kubernetes to manage and scale microservices efficiently, handling tasks such as deployment, scaling, and load balancing.

6. Continuous Integration and Deployment (CI/CD): Implementing automated pipelines to test, build, and deploy microservices rapidly and reliably.

7. Fault Isolation and Resilience: Designing microservices to be resilient to failures, with techniques such as circuit breakers, retries, and fallback mechanisms.

8. Monitoring and Observability: Implementing monitoring tools and practices to gain insights into the health, performance, and behavior of microservices in production.

9. Evolutionary Design: Embracing the idea of evolutionary architecture, where microservices can evolve independently over time to adapt to changing requirements and business needs.

10. Team Autonomy: Empowering development teams to own and operate their microservices independently, fostering a culture of ownership and accountability.

Guidelines for Developing Microservices

When embarking on the journey of developing microservices, it's essential to consider various factors to ensure success. Here are some key guidelines to keep in mind:

1. Benefits vs. Drawbacks

Microservices offer agility, scalability, and the ability to deploy independently, which can accelerate development and innovation. However, they also introduce complexities such as distributed system challenges, increased operational overhead, and potential communication issues between services. It's crucial for developers to weigh these pros and cons carefully.

2. Testing Considerations

Robust testing is paramount in a microservices architecture. Unit testing ensures that individual services function correctly, while integration and end-to-end testing validate interactions between services. Automation is key here to maintain efficiency and reliability in testing workflows.

3. API Gateway

API gateways act as a central entry point for clients to interact with microservices. They handle routing, authentication, and other cross-cutting concerns, simplifying client access and enhancing security by enforcing policies such as rate limiting and authentication.

4. Decentralized Data Management

In a microservices environment, data management becomes decentralized. Developers must consider strategies like eventual consistency models or using distributed databases to maintain data integrity and availability across services.

5. Versioning and Backward Compatibility

Versioning APIs and ensuring backward compatibility are crucial to minimize disruptions for clients when updates occur. This involves thoughtful API design, clear versioning strategies, and communication with stakeholders to manage transitions smoothly.

6. Monitoring and Observability Tools

Tools like Prometheus, Grafana, and Jaeger are invaluable for monitoring and observing microservices. They provide insights into service health, performance metrics, and tracing for diagnosing issues in distributed systems.

By incorporating these additional insights, you can provide developers with a more comprehensive understanding of the challenges and best practices associated with microservices architecture. It's all about equipping them with the knowledge and tools they need to succeed in building resilient and scalable systems.

1. Design Services Based on Business Capabilities

1. Identify the main functions of your business.
2. Divide these functions into manageable services.
3. Ensure each service has a specific task and isn't tightly connected to others.
4. Clearly define how services will communicate with each other.
5. Ensure Independence and Isolation of Services.

2. Design each microservice to handle one particular task

1. Use principles that keep services separate, focusing on their specific tasks.
2. Keep data storage separate for each service.
3. Use a message broker for services to exchange information.
4. Make sure services communicate indirectly through API gateways.
5. Put each service inside its own controlled environment using Docker or Kubernetes.

3. Use Lightweight Communication Methods

1. Consider using simple communication methods like REST, MQTT, STOMP, or AMQP.
2. This streamlines communication, making the application faster and more responsive.

4. Implement Fault Tolerance and Resilience

1. Use "circuit breakers" to isolate problems and stop them from affecting other services.
2. Retry operations that might fail temporarily.
3. Prevent resource overloads by using "bulkheads" to separate resources.
4. Detect problems quickly with proper monitoring and alerts.
5. Have a backup plan for when services aren't working perfectly.

5. Efficiently Monitor and Manage Microservices

1. Keep all logs in one place for easy access.
2. Set up tools to measure how well the services are performing.
3. Use distributed tracing to find and fix slow parts of the application.
4. Check if services are healthy and use a dashboard to see their status.
5. Use tools like Kubernetes to control the services effectively.

6. Ensure Microservices Security with Spring Security

1. Control access with Spring Security, giving different roles to users.
2. Secure communication between services using OAuth 2.0.
3. Protect important data by encrypting it.
4. Write code with security in mind to avoid problems.
5. Use a central system to manage who can access which services.
6. Consider adding extra security like two-factor authentication.
7. Make sure communication channels are secure with HTTPS.
8. Limit the rate at which someone can use a service to prevent attacks.

7. Testing Microservices

1. Test automatically to make sure everything works as intended.
2. Test each part of the service separately to catch problems early.
3. Check how well services work together in integration tests.
4. See how the system handles lots of requests in load testing.
5. Test services in different situations to find and fix problems.
6. Make sure data stays consistent across services in data integration tests.
7. Check for security issues with specific security testing.

Approaches used in the industry

There are a number of different approaches that can be used to size microservices. Some of the most common approaches include:

Domain-driven Sizing

This method involves looking at the different areas or aspects of the application that are related to the specific business or industry it serves.

For example, if it's an e-commerce application, the domains could be product catalog, shopping cart, user management, and payment processing. Each domain represents a distinct and separate part of the application. By analyzing the complexity of each domain, such as the number of features, interactions, and business rules involved, we can determine the appropriate size of microservices for each domain. This ensures that each microservice is designed to handle its specific set of responsibilities and aligns well with the business needs of the application.

Event-driven Sizing

This approach focuses on the events or actions that occur within the application. An event can be any significant occurrence, such as a user registration, product purchase, or inventory update. By identifying the different events in the application and assessing how frequently they happen, we can gauge the workload and traffic each microservice needs to handle.

For example, if a particular event occurs frequently and requires substantial processing, the corresponding microservice should be appropriately sized to handle the expected load and ensure smooth performance. By sizing microservices based on event frequency, we can distribute the workload effectively and ensure the efficient processing of events within the application.

Conclusion

Microservices are a great way to build scalable and maintainable applications. This article explains every you need to know about microservices, the benefits of microservices, and the challenges associated with them.

Do you want to enahance your microservices architecture? Hire a Java developer for your next project. 

Our developers are proficient in utilizing various tools and technologies, including service registry and discovery solutions like Eureka and Consul. They are adept at implementing API gateways, utilizing Spring Cloud Config for efficient configuration management, and ensuring security through protocols such as OAuth 2.0 and JWT.

The team also possesses expertise in utilizing tools for load balancing,utilizing event streaming and messaging technologies such as Apache Kafka and RabbitMQ, and containerization using Docker and Kubernetes.

We can help you design, develop, enhance your exisitng app, and deploy a microservices architecture that meet your specific needs. Contact us today to get started.