7 Alternatives to REST APIs

Representational State Transfer (REST) is an architectural style and protocol for building web services. It is a popular approach for designing web application programming interfaces (APIs) because it emphasizes scalability, simplicity, and modifiability.

Unlike the strict frameworks that govern API protocols like Simple Object Access Protocol (SOAP) or Extensible Markup Language remote procedure call (XML-RPC), REST protocols have historically been employed to simplify the process of API development, as they can be built using virtually any programming language and support a variety of data formats.

However, the emergence of several REST alternatives is forming a new flashpoint for API development over the next decade. This trend includes other protocols, patterns, and technologies like event-driven APIs, GraphQL, and gRPC. As these protocols achieve maturity and broader acceptance, it will become essential for API developers to understand how best to deploy REST alternatives across various platforms.

Let's explore what makes these REST alternatives so popular and the most common use cases that support their use in the field.

Why are REST alternatives gaining steam?

RESTful APIs are popular because they are flexible, easy to understand, and compatible with any programming language or platform that supports Hypertext Transfer Protocol (HTTP). They are also well-suited for building scalable and distributed systems, as they can leverage HTTP's caching and load-balancing capabilities.

REST prioritizes easy modification through resources and Uniform Resource Identifiers (URIs) representing data. This means developers can change the API structure without breaking existing client applications.

So why would developers use anything else? There are a few compelling reasons:

Evolving complexity. REST APIs are designed to overcome the complexity of earlier API protocols like SOAP, but they can become challenging to maintain as the number of endpoints and resources increases. This can make it difficult for developers to understand and modify the API over time.
Performance. For some use cases, REST APIs are scalable and can handle many requests. However, there may be better choices for real-time or low-latency applications, as they rely on multiple round-trip requests to retrieve data.
Evolving data requirements. REST APIs may require significant changes to support new use cases or data structures, leading to versioning and compatibility issues and increasing complexity and development time.
Specific use case requirements. There are specific use cases, such as real-time data streaming or low-power Internet of Things (IoT) devices (as mentioned above), where other protocols may be better suited than REST.
Developer preference. Developers may prefer using alternative protocols because they are more familiar with them or offer specific features or benefits that REST does not provide.

Alternatives to REST APIs

Here are the seven REST alternatives you need to know:

GraphQL

GraphQL is a runtime and query language for APIs that allows clients to request and receive only the data they require, making it more efficient than REST. With GraphQL, clients can specify the exact data they need and get it in a single request instead of making multiple requests to different endpoints as in REST. It's a great choice for data-driven applications with complex and evolving data requirements.

It may not be the best choice for applications that require strict data validation, applications that need to support a wide variety of clients, or user-facing apps like social media. Still, it is an excellent alternative to REST in situations requiring flexible and efficient data retrieval and manipulation. This is particularly true in applications with complex data models or mobile applications with limited connectivity.

gRPC

gRPC is an open-source framework developed by Google for building RPC APIs. It allows developers to define service interfaces and generate client and server code in multiple programming languages. gRPC uses protocol buffers and a language-agnostic data serialization format for efficient data transfer, making it ideal for high-performance applications.

gRPC may not be the best choice for a large volume of data manipulation or for applications that need to support a wide variety of clients. However, gRPC is known for its high performance and low overhead, making it a good pick for applications that require fast and efficient communication between services.

WebSockets

The WebSocket protocol enables bi-directional, real-time communication between clients and servers. Unlike REST, which is request/response-based, WebSockets allow servers to push data to clients as soon as it becomes available, making it ideal for applications that require real-time updates, such as chat applications and online gaming.

WebSockets may not be the best choice for applications that require complex data manipulation or for applications where scalability is a concern. However, it shines where real-time communication and low latency are required, thanks to a full-duplex, persistent connection between client and server. REST uses a less efficient request/response model.

MQTT

MQTT is a lightweight, open-source messaging protocol designed for IoT devices. It's a pub/sub protocol with a small packet size and low bandwidth, making it ideal for constrained networks and devices with limited processing power. MQTT can also handle intermittent network connectivity and supports Quality of Service (QoS) levels to ensure reliable message delivery.

It's not the best choice for complex interactions or data manipulation applications. But for use cases with lower bandwidth and battery life preservation — MQTT allows devices to "sleep" between messages, extending the battery life of IoT devices — it offers excellent capability.

Event-Driven Architecture (EDA)

In EDA, events trigger and communicate changes between different components or services within a system. This allows for real-time and reactive data processing and can reduce the need for repeated polling of resources, which can be resource-intensive and time-consuming in REST-based systems.

EDA is a good REST alternative for applications that require real-time data processing, scalability, and loose coupling between different components or services within a system. It's also well-suited for microservices architectures, allowing each microservice to operate independently and communicate with other services through events. This enables better scalability, flexibility, and resilience of the overall system.

FALCOR

Companies can also drive innovation in development. FALCOR is a JavaScript library developed by Netflix for building efficient and flexible APIs. It uses a "path-based" approach to data retrieval, representing data as a graph of interconnected paths rather than individual resources accessed through HTTP requests. It offers benefits like:

WebSocket support, which allows real-time data updates to be pushed to clients without requiring repeated polling
Declarative data fetching, where the client specifies the data it needs and the API responds with the requested data. This simplifies the client-side code and reduces the amount of data sent over the network.

The name "FALCOR" does not stand for anything. It was chosen by the developers at Netflix to represent the library's approach to data retrieval. It's inspired by the character of the same name from the 1980s movie "The NeverEnding Story," a dragon-like creature that can travel through different dimensions and worlds, much like FALCOR's ability to navigate complex data graphs.

Functions

PubNub’s Functions are JavaScript event handlers that can be executed on in-transit PubNub messages or in the request/response style of a RESTful API over HTTPS. For those who are familiar with Node.js and Express, the On Request event handler development is very similar. Functions can deploy new or additional real-time functionality like chat moderation and language translation.

Run your code within our network or leverage our existing integrations to transform, re-route, augment, filter and aggregate messages to detect and block spammers, measure averages, and more. All code is run at the edge for low latency and is robust enough that you don’t need to build your own infrastructure.

Facilitating innovation one REST alternative at a time

REST alternatives are gaining popularity due to their ability to solve challenges REST APIs face. Each alternative has its own unique strengths and use cases. When choosing a REST alternative, it's essential to consider the specific needs and requirements of the application — whether its scale for live events or real-time capabilities for Web3 — as well as the strengths and limitations of each REST alternative.

Ultimately, by exploring these alternatives, developers can build more efficient and effective APIs that meet the needs of modern applications.

Make your app come to life. Contact us to discuss your real-time project or, better yet, see it in action for yourself.

How can PubNub help you?

This article was originally published on PubNub.com

Our platform helps developers build, deliver, and manage real-time interactivity for web apps, mobile apps, and IoT devices.

The foundation of our platform is the industry's largest and most scalable real-time edge messaging network. With over 15 points-of-presence worldwide supporting 800 million monthly active users, and 99.999% reliability, you'll never have to worry about outages, concurrency limits, or any latency issues caused by traffic spikes.