by Microservices architecture approach provides opportunity for multiple services to work together to create a cohesive application. Since, all the services interact with each other via different APIs hence it requires an entity to manage all the api interaction across services. This entity is called API Gateway and is one of the most important entities in microservices architecture. In this article, we are going to discuss about API Gateway and its importance in microservices architecture approach.
Please check Introduction to Microservices Architecture for more information.
API Gateway
An API Gateway is a server that acts as a mediator between client and multiple microservices in the system. This entity is responsible for handling multiple tasks few of them are as follows:
- Authentication – Verifying the authentication of the client.
- Authorization – Verifying whether the client is authorized to use the service.
- Traffic management – This also allows to manage the traffic between client and microservices.
- Rate limiting – API Gateway ensures the microservices is not bombarded with high traffic and ensure smooth traffic flow.
- Request routing – Based on the request, It routes the message to intended microservice.
- Enhanced security – Since this is the single-entry point to the system, hence It helps in enhancing security by providing a centralized location.
In the below diagram, a sample API gateway implementation is shown where different gateways are implemented for different users. These gateways ensure only authorized information are accessed to users.
Importance
Services in a microservices architecture can be deployed and scaled independently which becomes very difficult to manage the various APIs which it exposes. API Gateway allows easier management of services as it provides a centralized location to manage various APIs services exposed and services can be scaled and update easily.
Also, since it provides rate limiting and routing facilities which helps improving the reliability of system by providing load balancing and high availability capabilities.
API Gateway Tools
Kong – This is an open-source API gateway which has lots of useful features such as rate limiting, load balancing, authentication etc. It supports various protocols such as HTTP, TCP and WebSocket etc and easy to integrate with other microservices tools.
AWS API Gateway – AWS API Gateway is a proprietary service provider. AWS Gateway provides services based on REST, HTTP and WebSocket protocols to handle all operations required. These can very easily integrate with other AWS tools such as logging, Access management etc.
As we discussed above the API gateway usability. It clearly indicates that it is a very critical component of microservices architecture. It provides reliability and performance improvements along with easier method of managing APIs exposed by various services which can also help the system greatly by supporting load-balancing and caching functionalities.
