The Difference Between Monolithic and Microservice Architecture

Suppose we have an eCommerce website that should have the following modules:

• User Management
• Order Management
• Inventory Management
• Procurement Management
• Payment
• Logistics

Monolithic Architecture:

In the monolithic architecture, all components in the program will be "one whole" and "an independent unit" and they are dependent on each other and constantly interact. In this architecture, all components have a database.
Monolithic programs are in one format, so there is no need to worry about the functionality of different parts of the program, and it is very easy to deploy monolithic programs because your program is not made of separate modules and you do not need to deploy different parts separately.
But changing the program or using modern technologies in this type of architecture is very difficult and sometimes not possible because the program is written all at once.

The advantages of monolithic architecture are:

• Easy deployment: An output file or directory makes the deployment program easier.
• Development: When an application is built with a single source code, it is easier to develop it.
• Performance: In a centralized source code and database, one API can often perform the same function as multiple APIs with microservices.
• Simple testing: Because an integrated application is a centralized unit, end-to-end testing can be done faster than a distributed application.
• Easy Debugging: With all the code in one place, it's easier to track down the problem.

Disadvantages of monolithic architecture:

• Slower development speed: A large and monolithic application makes development more complicated and slower.
• Scalability: You can't scale different parts of monolithic applications individually, you can only scale and upgrade the whole.
• Reliability: If there is an error in any module, it can affect the availability of the entire application.
• Adapting to new technologies: Any change in the framework or language affects the entire application, making changes often costly and time-consuming.
• Inflexibility: An integrated application is limited by the technologies used in the application.
• Deployment: A small change in an integrated application requires redeployment of the entire integrated application.

Microservice Architecture:

But in the microservice architecture, each component becomes an independent service, each of these services has its own logic and database and does its own work.
Each component, which is the independent module, is deployed separately and will not have any dependence on each other; To form a large application, the components will have their own interactions with each other through API, and data flow will be established between them.
One of the best advantages of programs with microservices architecture is that their scalability is infinite because we can upgrade each of the services individually. Also, because the components are independent, if one component has a problem or error, the activity of other components of the program will not be disrupted and the program will not crash.
On the other hand, when we implement an application based on microservices, its integration becomes a bit difficult because all its components are separate.

Disadvantages of microservice architecture:

• High complexity: Since in this architecture, the programs are distributed with components, we must establish the connection between each component and consider the database for each component. Also, components must be deployed separately.
• Resource distribution: Resource distribution in microservices is done manually and requires a lot of attention.
• System integration: When we implement an application based on microservices, its integration becomes a bit difficult because all the components are separate.
• Test writing: writing tests for applications that constantly use different APIs will be very difficult and time-consuming.

Advantages of microservices:

• Independent components: all services of this architecture can be updated and deployed separately.
• Easier understanding: Naturally, in this architecture, programs do not have a single source code, but we have a separate source code for each of the desired services, and these source codes are direct and not dependent on each other.
• Better scalability: One of the best advantages of programs with microservices architecture is that their scalability is infinite because we can upgrade each of the services individually.
• Flexibility in the choice of technology: Since the number of microservices is very large and all kinds of services are available for you, there is no limit to the choice of technology.
• Greater resistance to errors: each component of the program is independent, creating bugs and errors in one of them does not paralyze other parts of the program.

Conclusion:

Which architecture should I use?

Therefore, if your program is not big and you want to launch it quickly, it is recommended to use monolithic architecture. Also, keep in mind that building microservices applications requires technical knowledge, and doing such work without having work experience is considered very risky.

So as long as your application is not complex and you have enough knowledge to manage it, it is better to stay away from microservices architecture.

resources:

bytebytego
atlassian