Modern web development has been revolutionized by the emergence of GraphQL, a query language for APIs and a runtime for executing those queries. It provides a complete and understandable description of the data in your API and gives clients the power to ask for exactly what they need.
In comparison to traditional REST APIs, GraphQL shines in a few key areas:
| Feature | REST | GraphQL |
|---|---|---|
| Over-fetching / Under-fetching | Yes | No |
| Multiple Requests | Yes | No |
| Versioning | Yes | No |
| Real-time | No | Yes |
What is GraphQL?
GraphQL is a query language for APIs and a server-side runtime for executing those queries. It was developed internally by Facebook in 2012 before being publicly released in 2015.
const { graphql, buildSchema } = require('graphql');
const schema = buildSchema(`
type Query {
hello: String
}
`);
const root = { hello: () => 'Hello, world!' };
graphql(schema, '{ hello }', root).then((response) => {
console.log(response);
});In this simple example, we've defined a GraphQL schema that has a single hello field that returns a string, and a resolver function that returns the string "Hello, world!".
Benefits of GraphQL
By providing clients the power to ask for exactly what they need, GraphQL can prevent over-fetching and under-fetching problems commonly encountered with REST APIs.
Furthermore, it allows aggregating the data from multiple resources in a single request, saving costly network round trips. Real-time data updates are also a breeze with subscriptions.
Lastly, as GraphQL APIs return predictable results and self-document, they tend to require less maintenance and no versioning compared to REST APIs.
Conclusion
GraphQL represents a powerful, efficient alternative to traditional REST APIs. Its capabilities to prevent over-fetching and under-fetching, aggregate requests, provide real-time updates, and self-document make it an appealing choice for modern web application development.
