An API Proxy Explained: Can It Act As An API Gateway & Which One to Pick?

by Dan Goodin

02 Nov 2022

"Proxy & VPN Virtuoso. With a decade in the trenches of online privacy, Dan is your go-to guru for all things proxy and VPN. His sharp insights and candid reviews cut through the digital fog, guiding you to secure, anonymous browsing."

Proxy API Explained — *What is API proxy? Understanding API is not a problem after an explanation*

You must have come across the term API several times on the internet. It is an acronym for Application Programming Interface (API), which acts as a bridge between two applications and allows them to talk to each other.

When it comes to an API proxy server, that is a type of API gateway that acts as an interface between frontend and backend services. An API proxy is a shim that exposes the user interface, assists developers in accessing backend services, and makes API calls to backend services. This way, API proxies are useful for handling data transformations, routing, and security. Although an API Proxy server can act as an API Gateway, it differs from an API Gateway in some aspects. Still, understanding API is not that challenging. Let’s get started!

What is an API?

API refers to the Application Programming Interface (API), a commonly used term on the internet. Every smartphone user needs APIs to use different mobile apps and perform various functions online. Understanding APIs is essential to learn API proxies, API gateway, and the API Proxy vs. API gateway comparison.

But what does an API do? Let’s try to understand this term with an example.

Suppose you want to open a mobile app on your smartphone. As you click the app’s icon, it connects to the relevant server via the internet and starts sending data. The server retrieves the data, interprets it, performs the desired action, and sends the data back to the phone. Your application then again interprets the data and displays the output on your mobile screen in a readable format. All this communication process between a mobile app and the server occurs via an API.

Common examples of API integrations include weather snippets, digital payments via PayPal, mobile app logins, travel bookings, and Twitter bots.

What Is An API Proxy?

Proxy API scheme — *The scheme shows how proxy API works*

A proxy is something intermediary element, arbitrator, or intercessor for an existing process, communication cycle, or service. IT professionals use different proxies to decouple two software components: frontend and backend service. The process allows these components to evolve and function independently after getting deployed in two different locations.

If you have understood the concept of proxies, now let’s find out what API Proxy is. When we talk about an API Proxy server, it means an intermediary server between frontend (client) and backend services. When we use a mobile application, we send multiple requests handled by the API Proxy server, which then directs these requests to the appropriate backend service. In other words, an API Proxy server can act as an API Gateway that performs similar functions and routes clients’ requests to relevant backend services.

A proxy API is somewhat different from a gateway. The former has limited capabilities, while the latter is much more advanced regarding security, rate limiting, and API monitoring. Although a proxy API can act as an API Gateway, the two have different functions and cannot be entirely replaced by each other.

The biggest advantage of an API proxy is that it is simple, easy to use, and acts as a lightweight API gateway. It allows software and app developers to define an API by decoupling the frontend and backend services without making any code changes in the backend.

What is an API Gateway?

As explained earlier, a proxy API can act as a Gateway to manage client requests and route them to the appropriate backend services. However, an API Gateway comes with advanced functionalities and provides an additional layer of security.

For instance, when an API Gateway receives clients’ requests for server access, it enforces authentication and authorization policies to ensure enhanced security. Once complete authentication, the requests are forwarded to the backend services. This additional step minimizes security risks involved in enterprise API management and offers better API monitoring.

With an API Gateway, software developers can create, secure, and maintain several APIs and process thousands of concurrent API calls. Instead of worrying about the underlying infrastructures, developers can use an API Gateway for API security & monitoring, traffic management, API version management, and access control via authorization. As your API traffic increases, API Gateway scales automatically, and users only pay for the API calls received.

From creating and managing APIs to exposing data from other sources like AWS services, SOAP web services, and Lambda, API Gateways offer everything developers need for efficient API management.

An API Proxy Can Act As An API Gateway

API Proxy and API Gateway have several common functionalities: API lifecycle management, routing client requests to the appropriate backend service, and API monitoring. In some cases, API proxies can also perform API security. That means a proxy API can act as an API Gateway for effective enterprise API management.

But the question is, which one is more optimal and overall better? Who wins the race when it comes to API Proxy vs. API Gateway?

There is no 100% clear answer to this question because your choice of an API Proxy or an API Gateway depends on your organizational needs. You can use an API Proxy server to get started with a basic API. However, API Gateway is essential if you want to meet all your enterprise API needs because Proxy API comes with several limitations.

So, let’s explore the pros and cons of using an API Proxy as an API Gateway.

Pros

Given below are some reasons why you should use an API Proxy as an API Gateway:

Unlike traditional API Gateways, which are complicated to set up, API Proxies are easy to manage and perform basic enterprise API management operations.
API Proxies are more scalable because you can deploy them independently of your application.
Being a simple, highly efficient, and lightweight API gateway, an API Proxy Server is much easier to handle and maintain than a traditional API Gateway.
The simplicity of Proxy API makes it easier for beginners or entry-level developers to use them for API monitoring, API lifecycle management, and API security.
API proxies are relatively cheaper than traditional API Gateways due to small operational costs.

Cons

Given below are some reasons why you shouldn’t use an API Proxy as an API Gateway:

An API Proxy server offers limited integration options compared to an API Gateway, which is much more efficient and allows developers to modernize their applications with many integrations.
API proxies allow you to create APIs and expose data from publically accessible sources only.
API proxies lack the API orchestration capabilities necessary to construct service calls appropriately. For this purpose, you need an API Gateway.
API Gateways perform some exclusive functions that are not available with API proxies. These include finding information via a lookup service, constructing cells using pre-programmed logic, or managing detail requests for specific items on the catalog.
API Gateways offer sophisticated security and monitoring features that allow developers to create and manage exceptional APIs with better performance. These features cannot be accessed with Proxy API.

How to Create or Where to Get an API Proxy

Creating an API proxy server is very simple and easy. However, you must stay organized and focused regarding API proxy design and development. Even a minor mistake could reduce the dependency between two components of software and fail to deliver the expected results.

Hence, before you start creating an API Proxy, analyze the following aspects in order:

1. List the Associated APIs

You need a single or both APIs to design an API Proxy server. Hence, it is necessary to compare both APIs and identify the features desired for your API Proxy. If you already have the backend-facing API of your API Proxy, determine whether the addition of minimal features will be enough for scalable implementation or not. This step will help you make an informed, data-driven decision for expected outcomes.

2. Workflow Mapping

Workflow mapping enables developers to continuously review the messages flowing between the frontend and backend elements while designing an API Proxy. The flow should be optimized in terms of performance and cost to take timely action when required. For instance, you may need to make your API proxy scalable using highly scalable frontend elements. That will help you effectively manage the limited capacity in the backend elements.

3. Select the Appropriate Development Model

While implementing the frontend and backend components, developers use different languages, middleware tools, and data structures. You must be careful while selecting the appropriate language, middleware tool, and data structure that fits the APIs and the hosting platform. Moreover, determine which policies are essential to support the application features along with their complexity. Similarly, follow stateless development principles to make your API Proxy resilient or more scalable.

4. Choose an API Proxy Tool with the Necessary Policy Support

Choosing an API Proxy toolkit with built-in support for API proxy policies is highly recommended. Choosing a toolkit with extended capabilities will help you design optimal API proxies and eliminate the need for redoing the process with changing requirements.

5. Functional and Load Testing

The cross-functional nature of API proxies makes them highly sensitive to the interfaces of the APIs of different components. It is, therefore, necessary to thoroughly test the parameter combinations and changes in data structures. For this purpose, you must apply realistic functional and load testing to your API Proxy server to ensure it won’t interfere with the UI and show exceptional performance under different environments.

6. Add the API Proxy to the Dependency List

As explained earlier, API proxies are highly sensitive and could become nonfunctional even with a minor change to either API. Data or parameter issues could arise in some cases, making operations incorrect. To avoid these problems, remember to add the newly created API Proxy to the dependency list for both APIs.

Once all sections have been checked, follow these simple steps to create an API Proxy via Edge UI:

1. Go to apigee.com/edge in your browser and sign in to your account

2. In your dashboard, tap “API Proxies” under the “Develop” option

3. Choose your preferred environment to create a new API Proxy from the Apigee UI

4. Tap Create New and select the proxy type

Create proxy API — *Tap or click Create New and select an optimal proxy type*

5. Reverse Proxy is the most commonly used method. Select this option from the list that will display the Proxy details page

6. Configure your proxy details:

Proxy Name: Give a unique name to your Proxy (like myproxy)
Proxy Base Path: Set your path to /myproxy
Description: Enter a short description for your new API Proxy (Note: This step is optional)
Target (Existing API): Enter https://mocktarget.apigee.net to define the target URL invoked by the Apigee Edge when a user requests the API Proxy.

7. Preview your proxy details and tap the Next button

8. In the Policies section, select Pass through (no authorization) under Common policies and tap Next

9. In the Virtual Hosts section, tick both default and secure and tap Next

10. Select the Test environment under Optional Deployment in the Summary section and tap the Create and deploy button.

Proxy summary — *The final step is to test and deploy*

11. Congratulations! You have created a new API Proxy in your desired test environment. Tap Edit proxy if you want to make any changes, or tap Go to the proxy list to check the list of API proxies.

The deployed proxy — *The proxy can handle requests now*

Final Words

An API refers to the Application Programming Interface (API), which acts as a bridge between two apps and assists them in communication. Therefore, those are intermediary servers between frontend and backend services that handle user requests and routine them to appropriate backend services.

An API Proxy can act as an API Gateway to perform common functions like API monitoring, security, client request routine, and API lifecycle management. However, API Gateway is much more advanced and equipped with powerful features. API Gateway provides an additional layer of security, enforces authentication and authorization policies, and allows developers to process thousands of concurrent API calls.

An API Proxy can act as an API Gateway if you want simplified enterprise API management. However, always prefer an API Gateway to meet your enterprise API needs. Hence, consider your organizational needs whenever you need to decide on API Proxy vs. API Gateway.