GraphQL and REST API: What’s the difference?

APIs, the conduits through which software components interact and data flows across the Internet, are the lifeblood of modern web services. API technologies such as SOAP (Web Services Messaging Protocol), REST (architectural styles), and GraphQL (programming languages ​​and tools) simplify software development by enabling integration of third-party data and services. APIs also enable businesses to provide secure service functions and data exchange to their employees, business partners, and users.

Despite the different types of APIs, the conversation has been dominated in recent years by debates about two major paradigms: Representational State Transfer (REST) ​​and GraphQL. Both offer a variety of benefits and are therefore deployed in networking projects around the world. However, how data traffic is managed varies greatly. Here we break down these differences and discuss how enterprises can use REST and GraphQL APIs to optimize their networks.

What are REST and GraphQL APIs?

Comparing the two requires understanding REST and GraphQL APIs individually.

remain

Developed in the early 2000s, REST is a structured architectural style for networked hypermedia applications, designed to use a stateless, client/server, cacheable communication protocol. REST API, also known as RESTful API, is the driver of the REST architecture.

REST APIs use unique resource identifiers (URIs) to address resources. REST APIs work by allowing various endpoints to perform CRUD (“create”, “read”, “update”, and “delete”) operations on network resources. You use predefined data types, called media types or MIME types, to determine the shape and size of resources you provide to clients. The most common formats are JSON and XML (and sometimes HTML or plain text).

When a client requests a resource, the server processes the query and returns any data associated with that resource. The response includes HTTP response codes such as “200 OK” (for a successful REST request) and “404 Not Found” (for a non-existent resource).

GraphQL

GraphQL is a query language and API runtime developed internally by Facebook in 2012 before becoming open source in 2015.

GraphQL is defined by an API schema written in the GraphQL schema definition language. Each schema specifies data types and relationships between types that users can query or modify. The resolver supports each field in the schema. Interpreters provide instructions for converting GraphQL queries, transformations, and subscriptions into data and retrieve data from databases, cloud services, and other sources. Resolvers also provide data format specifications and allow the system to link data from different sources together.

Unlike REST, which typically uses multiple endpoints to fetch data and perform network operations, GraphQL exposes a data model using a single endpoint that sends GraphQL requests regardless of what the client is requesting. The API then accesses resource properties and follows cross-resource references to get all the data the client needs to the GraphQL server in a single query.

Both GraphQL and REST APIs are resource-based data exchanges that use HTTP methods (such as PUT and GET requests) that specify what operations the client can perform. However, there are key differences that explain why RESTful systems, as well as the proliferation of GraphQL, have such staying power.

Differences between GraphQL and REST API

GraphQL provides an efficient and flexible addition to REST. GraphQL APIs are often considered an upgrade to RESTful environments, especially given their ability to foster collaboration between front-end and back-end teams. GraphQL provides the logical next step in your organization’s API journey, helping solve common problems with REST.

However, REST has been the standard for API architecture for a long time, and many developers and architects still use RESTful constructs to manage their IT networks. Therefore, understanding the differences between the two is essential to any organization’s IT management strategy.

REST and GraphQL APIs are managed differently.

data retrieval

Because REST relies on multiple endpoints and stateless interactions, where every API request is processed as a new query independently of other requests, the client receives all pieces of data associated with the resource. Even if the client only needs a subset of the data, it still receives all the data (overfetching). And when a client needs data that spans multiple resources, RESTful systems often force the client to query each resource individually to compensate for inadequate data retrieval (underfetching) in the initial request. GraphQL APIs use a single GraphQL endpoint to provide clients with accurate and comprehensive data responses in one round trip of a single request, eliminating over- and under-fetching issues.

version control

In a REST architecture, teams must modify data structures and version APIs to prevent system errors and service interruptions for end users. This means that developers must create a new endpoint each time they make a change, which can result in multiple API versions and complicate maintenance. GraphQL reduces the need for versioning by allowing clients to specify data requirements in queries. Adding a new field to the server will not affect clients that do not need the field. Conversely, if a field is no longer used, clients can continue to request that field until their queries are updated.

Error handling

REST APIs must Use HTTP status codes to indicate the status or success of a request, and each status code has a specific meaning. A successful HTTP request may return a 200 status code, while a client error may return a 400 status code and a server error may return a 500 status code.

Although this approach to status reporting may seem simpler at first glance, HTTP status codes are often more useful to web users than the API itself, especially when errors occur. REST doesn’t have a specification for errors, so API errors may show up as transport errors or not show up with a status code at all. This dynamic may require employees to read status documentation to understand what errors mean or how errors are propagated within the infrastructure.

With a GraphQL API, every request returns a 200 OK status code, regardless of whether an error occurred. This is because errors are not communicated using HTTP status codes (except transport errors). Instead, the system passes errors in the response body along with the data, so the client must parse the data payload to determine whether the request was successful.

That said, GraphQL has a specification for errors, making it easier to distinguish API errors from transport errors. It may be preferable to build a GraphQL API because the exact nature of the error appears in the “Error” entry in the response body.

real-time data

REST does not have native support for real-time updates. If an app requires real-time functionality, developers typically need to implement techniques such as long polling (where the client repeatedly polls the server for new data) and server-sent events, which can add complexity to the application.

However, GraphQL includes built-in support for real-time updates through subscriptions. Subscriptions maintain a reliable connection to the server, allowing the server to push updates to clients whenever certain events occur.

Tools and Environment

REST environments are well-established, with a variety of tools, libraries, and frameworks available to developers. Nonetheless, REST APIs require teams to explore multiple endpoints and understand each API’s unique rules and patterns.

Although the GraphQL API is relatively new, the GraphQL environment has grown tremendously since its introduction, with a variety of tools and libraries available for both server and client development. Tools like GraphiQL and GraphQL Playground provide powerful in-browser integrated development environments (IDEs) for exploring and testing GraphQL APIs. Additionally, GraphQL provides strong support for code generation, which simplifies client-side development.

caching

REST APIs use mechanisms such as eTags and last modified headers to cache API calls. Although these caching strategies are effective, they can be complex to implement and may not be suitable for all use cases.

GraphQL APIs can be more difficult to cache due to the dynamic nature of queries. However, deploying persisted queries, response caching, and server-side caching can alleviate these issues and simplify broader caching operations in your GraphQL architecture.

When to use GraphQL and REST APIs

Neither REST nor GraphQL APIs are inherently better. A versatile tool suitable for a variety of tasks.

REST is generally easier to implement and can be a good choice when a simple, cacheable communication protocol with strict access controls is preferred (for example, for public e-commerce sites like Shopify and GitHub). Considering the risk of not enough or too much fetching, REST APIs are best suited for:

• Enterprises using smaller apps with simpler data profiles
• Enterprises without complex data query requirements
• Companies where most of their customer base uses data and operations in similar ways

GraphQL APIs can support more flexible and efficient data fetching, improving system performance and ease of use for developers. These features make GraphQL especially useful for building APIs in complex environments where front-end requirements change rapidly. These include:

• Businesses that have limited bandwidth and want to limit calls and responses
• Businesses looking to combine data points on one endpoint
• A company with very diverse customer requests

Although they use different approaches, both GraphQL and REST APIs have the potential to significantly improve network scalability and server performance.

Take control of your API environment with IBM API Connect.

Whether you deploy REST or GraphQL APIs, or a combination of the two, your business benefits from a wide range of potential applications, including implementations of different programming languages ​​(e.g. JavaScript), integration with microservices, and serverless architectures. You can enjoy it. IBM API Connect allows you to optimize your IT infrastructure using both API types.

IBM API Connect is a full lifecycle API management solution that helps you create, manage, secure, socialize and monetize APIs and drive digital transformation across data center and cloud environments. This means both businesses and customers can power digital apps and drive innovation in real time.

API Connect allows enterprises to ensure they are operating at the leading edge of API management, which will prove invaluable in computing environments that will become larger, more complex, and more competitive over time.

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