A microservice is component of website/software which has its own database and is managed separately. Let’s take an example of Amazon website. Amazon has many features on its site i.e. searching products, cart, sponsored products, listing products and many more. Now all these features are coded into separate components. Searching products is a separate component and has its own database and code set. Similarly all other main components behave same. The benefit of separating whole website into microservice/component is that website/software is managed easily and it can be upgraded more efficiently.
You will need to adopt microservice if your website/software is growing rapidly. On the other hand, if you use the traditional system to manage your website then on updating a single line of code, you have to check the whole website if it works correctly. If you use microservice then you only need to change the code of microservice without touching and checking the whole code of the website.
On the traditional website, you have to add a number of developers and servers as your website needs more features or your website gets more traffic. But by using microservice, you will only need a server for the feature (microservice) which is used most on your website. If your website user use search feature most of the time then you only need to add more processing power (server) to only search microservice. You can assign a developer to each microservice and they can easily manage your website.
Microservices vs SOA:
In SOA (service-oriented architecture) we use 3rd party service and integrate with our website. Like we integrate PayPal with our website. While in microservices, we divide our website code into small components also known as microservice.
Advantages of microservices
Adding and removing modules is easy:
If you have a large business website and you are using microservices then adding and removing any feature is easy. It will not affect the whole website as modules have its own database and limit.
Deployment is fast:
The microservices or modules of the website are only loaded when required so it can make the application faster to load. Also, deployment time of microservice is fast as a compared monolithic system.
Modules can be written in any language:
Modules in the system can be written in any computer language and all the modules within the system can communicate with each other through common language.
Easy to understand:
If you want to hire new developers in the company then it is easy for new developers to understand microservice. Developers don’t need to understand coding and design patterns of the whole website but only the required module in which they work.
Replacing microservice code is easy:
If you want to replace computer language for a specific service then it is easy to do so. Modules (microservice) are loosely coupled i.e. it will not affect all the website but you will need only update little code. If you want to change the language of any module from java to php then it is easy for developers to do so.
Disadvantages of microservices
Multiple databases involved:
As all the modules in the system have multiple databases so it is painful to manage all the independent databases and track the transactions.
Skilled developers needed:
It is difficult to implement microservice in the system. Also, the communication between microservices is tough to handle for the developers.
Making remote calls is complex:
It becomes complex to make remote calls and handling errors if you add more services to the system. Making requests and messages among modules sometimes become complex to handle.
In a monolithic system, testing is done on the system as a whole. While for microservices, testing is done on all the services and then checking all the individual services for any update is time-consuming.
Examples of microservices
Websites using microservices architecture are below:-