API Gateway: Why is it Important?

In this revolutionary age for software, the rapid rate at which new architectural patterns have emerged has significantly impacted the way enterprises are now choosing to build, deploy and consume services. These changes have also welcomed innovative approaches to project workflows, opening the doors for DevOps and engineering teams to automate key areas of their API lifecycles and simplify complexity across the board. The solution? API Gateway.

What is an API gateway?

An API gateway accepts all API calls and then acts as a reverse proxy, retrieving resources from backend applications on behalf of the client application. It not only accepts API calls — it also handles tasks related to API services like user authentication, rate limiting, monitoring, and more.

To help you understand what an API gateway is, let’s use an analogy. Think of an API gateway like a front door. Behind the door are the backend services that client applications want access to. The client — also known as the API consumer — makes their request at the door, perhaps verifies their identity, and then waits for the data requested to be delivered. Behind the door, where the client can’t see, their request is routed to the relevant part of the API system and the response is forwarded back to the client.

How does it work?

The beauty of modern-day software systems lies in their ability to handle complex operations with ease.

The introduction of an API Gateway is no different. This innovative technology acts as a buffer between clients and backend services, taking care of all error-detection procedures while also granting access privileges where needed. At the core of this lies a well-structured architecture that enables proper routing based on request paths and other relevant factors. The bread-and-butter of a microservices architecture lies in its efficient communication method within an ecosystem of multiple self-contained services. Upon reception of its first contact, the backend service sends back responses through the API Gateway once processing completes. After this step, the Gateway takes over by analyzing these outputs before relaying them back to their intended party – clients seeking collaboration with various involved services using one unified point of access. Furthermore, not only does an API Gateway provide credible clustering but also has options like working as a proxy server that accepts requests instead and directs actions accordingly.

In today’s fast-paced world of digital development, efficiency is everything — which is why the API Gateway has become so important in modern software projects. Acting as a central point of control for APIs across microservices architectures, this essential tool delivers enhanced performance thanks to smart task management like caching and load balancing.

Why use an API Gateway?

Most enterprise APIs are deployed using gateways today. API gateways are being used more due to the increase of use in microservices. Microservices allow an application to be deconstructed into several loosely-coupled services because each microservice requires its own functionality. Microservices make it easier to develop, deploy, and maintain the different functions of an application, but they can also make it more difficult for customers to access the application quickly and securely. An API gateway is the solution to this problem. Rather than making customers request access to each microservice individually, the gateway is that single point of entry for the requests, which disburses them to the appropriate service, gathers the results, and conveys that back to the requestor. The primary reason to use an API gateway, this function is referred to as routing by developers. For example, API gateways help your company manage the traffic generated by calls from say a mobile application like Uber and a backend application like Google Maps.

They are vital to successful API management. As the main proxy connecting your customers with your services, the gateway supports important administration and security functions, including authentication, metric collection, input validation, and response transformation.

Benefits of API gateways

An API gateway’s primary benefit is that it standardizes and centralizes the delivery of services through APIs or microservices. Beyond this, they also help secure and organize an organization’s API-based integrations in a number of ways.

• Simplify service delivery. They can combine multiple API calls to request and retrieve data and services, which reduces the volume of requests and traffic. This streamlines the API process and can improve the user experience, particularly for mobile applications.
• Provide flexibility. They are highly configurable. Developers can encapsulate the internal structure of an application in multiple ways, to invoke multiple back-end services and aggregate the results.
• Extend legacy applications. Enterprises that rely on legacy applications can use API gateways to work with those apps and even extend their functionality, as an alternative to a broader and more complicated (and expensive) migration.
• Contribute to monitoring and observability. Most organizations rely on specific tools for monitoring activity through APIs, but an API gateway can help assist these efforts. It logs can help pinpoint an issue during a monitoring failure event.

Challenges of API gateways

• Response time: While latency and response time are often decreased due to requests traveling more efficiently, the additional step of a request passing through an API gateway can potentially add to response time.
• Dependencies: Anytime a business adds, changes, or removes a microservice, it must update its API gateway. That can be challenging with an application that has evolved from having just a few microservices to encompassing many. However, creating API design rules can help with this.
• Complexity: Routing logic can make communication with microservices more complex. The API gateway is another system that must be developed, deployed, and maintained.
• Security: Because an API gateway touches many areas of an enterprise’s systems, its compromise can seriously impact an application’s safety.
• Reliability: If there’s only one API gateway and it goes down, the whole application becomes unavailable. Creating multiple API gateways and using load balancers can help avoid this situation.

API gateway vs. API management

API management solutions enable you to manage the entire API lifecycle. You can use these solutions to manage how you publish and share APIs with developers and partners, and control who can access each API according to specific user roles and permissions.

They also provide monitoring functionality to track usage statistics for each published API. These insights can answer important questions, such as which APIs are most popular among external clients, what clients do with APIs after they are published, the geo-distribution of requests, and how many APIs per second each endpoint receives.

API gateways might be components within an overall API management solution, or they can be used as a standalone solution. An API gateway is only a proxy service situated in front of existing infrastructure, while an API management solution encompasses the entire API lifecycle. Organizations typically use API gateways and API management platforms together to:

• Enhance the back-end architecture and gain more control over a multi-API system.
• Improve observability of API-based applications.
• Improve end-user experience when consuming company data or features via APIs.

Conclusion

An API gateway plays a crucial role in serving as an interface between clients and backend microservices, simplifying communication and enhancing overall performance. However, while some API gateways may offer limited web security functionalities, organizations must recognize the need for robust protection against sophisticated threats (such as API attacks) and should include additional security measures such as a comprehensive WAAP (web application and API protection) platform.