Introduction to Microservice Architecture

In this article, let's see what a microservice architecture is and how it helps the IT industry develop scalable and maintainable applications.

Before knowing about microservices, we need to know about the monolithic architecture and its disadvantages.

Monolithic architecture is a traditional model for designing software applications. In this architecture, all components of the application are tightly coupled and interdependent, forming a single, unified unit.

Characteristics of monolithic architecture

Unified Codebase: The user interface, server-side functionality, and database activities of the application are all handled by a single codebase.

One Deployable Unit: The application is developed, tested, and made available as a single unit.

Centralized Management: All aspects of the application are managed and maintained within a single platform.

Homogeneous Environment: The application typically runs in a single runtime environment, often using the same technology stack throughout.

Disadvantage of monolithic architecture

• While monolithic architectures can simplify initial development and deployment, they can become complicated as the application grows in size and complexity.

• Scaling requires deploying the entire application, even if only one part needs more resources.

• Additionally, making changes or updates can be risky since a single error can impact the entire system.

What is Microservice?

To address the issues of monolithic architecture IT industry came adapted microservice architecture.

Microservices are a software architecture style that structures an application as a collection of loosely coupled services.

Since each service is designed to accomplish a specific task, it can be independently developed, deployed, and scaled.

With the help of microservices architecture the development team can focus on developing multiple services and deploy them independently.

Microservice Communication

Though microservices architecture breaks the single monolithic application into multiple independent services, there is one challenge that need to be addressed.

It is how microservices communicate with each others. There are 2 types of microservice communication:

Synchronous Communication

If a client sends a request to the microservice and waits for the response from it then its know as synchronous communication. This type of communication is also known as client server communication.

Usually Rest API is used for this type of communication, where the client will send an request through api to a microservice, and microservice process the request and sends the response back to the client.

This approach is the simpliest approach but it has some problem where there may be performance bottlenecks and failure in microservice can block the entire communication.

Asynchronous Communication

In asynchronous communication, the client will send a message to the microservice without waiting for an immediate response.

Rather, the microservice receives the message, processes it, and then depending on the circumstances sends a response. Asynchronous communication is frequently accomplished via message brokers, such as Kafka or RabbitMQ.

Because services can continue to operate independently even in the event that one or more are temporarily unavailable, this method increases system resilience. On the other hand, it complicates message processing and eventual consistency handling.

Advantages of Microservices

• Scalability: Individual services can be scaled based on the network load.
• Flexibility: Different programming languages can be used to write different services.
• Resilience: The system doesn't collapse if one of its services fails.
• Deployment Ease: As each services are independent, we can deploy them seperately.
• Technological Diversity: Groups are able to select the most appropriate tool for the tasks at hand.

Disadvantages of Microservices

• Complexity: Managing multiple services can be more complex than a monolithic architecture.
• Development and Testing: More effort is required to integrate and test services.
• Network Latency: As services communicate between each other, this increases the network latency.
• Data Integrity: Ensuring data consistency across services can be challenging.
• Operational Overhead: Requires robust infrastructure for monitoring, logging, and fault tolerance.