Making an Informed Choice: Comparing REST API and GraphQL

5 min readMay 26, 2023

Selecting the ideal API style for your project is a critical decision that can significantly impact its performance, flexibility, and developer experience. In this blog post, we will delve into the characteristics, strengths, and considerations of two leading contenders: REST API and GraphQL. By understanding the nuances of each approach, you’ll be better equipped to make an informed choice.

Understanding REST API

REST (Representational State Transfer) has long been the go-to architectural style for building APIs. It follows a set of principles, utilizing HTTP methods and resource-based URLs to perform operations on data.

The following principles are:

Client-Server Decouple: This refers to the separation between the client (front end) and the server (back end). This separation means that the client and server can operate independently, communicating only through the API endpoints. This decoupling allows them to evolve and scale independently, with changes on one side not directly affecting the other.
Uniform Interface: Data seen in the interface is identical across all devices.
Statelessness: In a REST API, the server follows the statelessness principle, which means that it does not maintain any information about the client’s previous requests or the overall state of the application. When a client makes a request to a REST API endpoint, the server treats each request as an independent and self-contained operation.
Cacheability: Caching and session storage is permitted, but they must be configured to allow end-users to opt out of data caching.
Layered System Architecture: APIs must be designed so that neither the client nor the server can tell whether they’re communicating directly or through an intermediary.

The diagram below is of basic REST architecture. It shows how requests and responses are typically handled.

Obviously, the above principles add to the advantages of the Rest API, but Restful APIs come with certain limitations such as:

Over-fetching and under-fetching: REST APIs often return fixed data structures, leading to either over-fetching (retrieving more data than needed) or under-fetching (requiring multiple requests to gather all the required data).
Versioning and breaking changes: As projects evolve, introducing changes to REST APIs can be challenging and may require versioning to avoid breaking existing client implementations.
Client-server coupling: Clients are tightly coupled to the server’s data structure, making it harder to iterate independently on the client side.

So we have seen now what REST API’s could offer, let’s just evaluate GraphQL a bit too.

Introducing GraphQL :

GraphQL is a query language and runtime for APIs. It was developed by Facebook and later open-sourced. GraphQL allows clients to request and receive the precise data they need from a server in a flexible and efficient manner.

In GraphQL, clients can send a single request to the server, specifying the structure of the response they desire. The query can include nested fields and related data, allowing clients to traverse complex relationships and gather data in a hierarchical manner.

The above diagram is a typical representation of GraphQL architecture.

Clients make requests from different devices, and GraphQL handles their requests and returns only their requested data. This neatly solves the problem of over-fetching and under-fetching in RESTful APIs.

So if we have a careful look on the advantages offered here are some:

Advantages of GraphQL:

Efficient data retrieval: With GraphQL, clients can specify their data requirements in a single request, eliminating over-fetching and under-fetching issues.
Flexible and hierarchical queries: In GraphQL, clients can specify the desired response structure, including fields and relationships. This enables traversing complex data relationships and fetching related data hierarchically in a single query. This approach reduces the need for multiple asynchronous requests to different endpoints, as required in typical REST APIs. By avoiding over-fetching and minimizing data transfer, GraphQL improves performance and simplifies data merging on the client side.
Rapid development and iteration: GraphQL’s decoupling refers to the separation of concerns between the frontend and backend teams. GraphQL enables frontend developers to specify their data requirements precisely through GraphQL queries, eliminating the need for backend developers to anticipate all possible client data needs. This decoupling empowers frontend and backend teams to work independently, iterate quickly, and evolve their APIs without tightly coupling them to each other’s implementation details.
Strongly typed schema: GraphQL APIs expose a strongly typed schema that serves as a contract between the client and server, enabling better collaboration, documentation, and tooling support.

No doubt the advantages look lucrative here are a few limitations as well that come with Grapql such:

Learning curve: Adopting GraphQL requires understanding its query language and the unique architectural concepts it introduces. This learning curve may impact the ramp-up time for developers new to GraphQL.
Increased complexity: Implementing GraphQL may require additional infrastructure and tooling to handle query parsing, validation, and execution. It introduces complexity compared to the simplicity of REST APIs.
Caching challenges: Due to the flexibility of GraphQL queries, caching becomes more complex and may require additional effort to implement correctly.

Choosing the Right API Style

Consider the following factors when deciding between REST API and GraphQL for your project:

Complexity of data relationships: If your data has complex interdependencies, GraphQL’s flexible querying capabilities provide an advantage in retrieving related data efficiently.
Performance and efficiency requirements: If optimizing network usage, reducing requests, and minimizing data transfer is crucial, GraphQL’s ability to request precise data can be beneficial.

Conclusion:

When choosing between REST API and GraphQL, carefully assess your project’s requirements and constraints. REST API offers simplicity and compatibility, while GraphQL provides efficient data retrieval and flexibility. By considering the complexities of your data relationships and performance needs, you can make an informed decision that aligns with your project goals.

Happy coding !!