GraphQL vs. REST: Why Your Next API Might Prefer GraphQL

Source: Dev.to

Introduction

Hey Dev.to community!

We’ve all been there. You’re building a new application, and it’s time to decide how your frontend will talk to your backend. For years, REST has been the undisputed king of API design, and for good reason – it’s robust, widely understood, and incredibly flexible. But in recent years, a new contender has emerged named GraphQL.

While REST isn’t going anywhere, GraphQL offers some compelling advantages that are making developers seriously reconsider their API strategy. Let’s dive into why GraphQL might be the better choice for your next project.

The Problem with REST (Sometimes)

Don’t get me wrong, I love REST. It’s fantastic for many use cases. However, as applications grow in complexity and user interfaces become more dynamic, REST can start to show its limitations, particularly in two key areas:

• Over‑fetching
  Imagine you need to display a user’s name and email on a profile page. With REST, you might hit an endpoint like /users/:id. This endpoint, however, might return a ton of extra data you don’t need right now – their address, order history, preferences, etc. All this extra data has to be transferred over the network, wasting bandwidth and potentially slowing down your application.

• Under‑fetching
  Conversely, if you need to display a user’s name, their last 3 posts, and the comments on those posts, you might end up making multiple requests: /users/:id, then /users/:id/posts, and then /posts/:id/comments for each post. This “n+1” problem leads to multiple round trips to the server, increasing latency.

• Versioning and Multiple Endpoints
  As your application evolves, so does your API. You might find yourself creating /v1/users, then /v2/users to handle changes, leading to a sprawling set of endpoints that can be hard to manage and document.

Enter GraphQL: A Better Way to Ask for Data

GraphQL, developed by Facebook, isn’t a database technology; it’s a query language for your API and a runtime for fulfilling those queries with your existing data. The core idea is simple yet powerful: the client dictates exactly what data it needs.

Key Advantages of GraphQL

Single Endpoint, Precise Data Fetching

Instead of numerous REST endpoints, a GraphQL API typically exposes a single endpoint (e.g., /graphql). The client then sends a query describing exactly what data it wants, and the server responds with only that data.

query GetUserAndPosts($id: ID!) {
  user(id: $id) {
    name
    email
    posts {
      title
      content
      comments {
        text
      }
    }
  }
}

The server receives this query and returns a JSON object matching its structure. No over‑fetching, no under‑fetching, just efficient data retrieval in a single request!

Reduced Network Requests

Because you can request multiple resources in a single query (e.g., user, their posts, and comments on those posts), you drastically reduce the number of HTTP requests your client needs to make. This is a game‑changer for mobile applications or environments with high latency.

Strongly Typed Schema

GraphQL APIs are defined by a schema, which acts as a contract between the client and the server. This schema defines all the available data types and operations. Tools can then use this schema for:

• Auto‑completion and validation in development environments.
• Automatic documentation generation, ensuring your API docs are always up‑to‑date.
• Type safety, catching errors before runtime.

No Versioning Headaches (Mostly)

With a well‑designed GraphQL schema, you can add new fields and types without breaking existing clients. Clients simply ignore new fields they don’t explicitly request. Deprecating fields is also cleaner, as clients can be warned without forcing a breaking change across the entire API.

Real‑time Capabilities (Subscriptions)

GraphQL has built-in support for subscriptions, allowing clients to subscribe to events and receive real‑time updates from the server. This is incredibly powerful for chat applications, live dashboards, and other real‑time features.