GraphQL is an open-source data query and manipulation language for APIs, and a runtime for fulfilling queries with your existing data. It was developed by Facebook in 2012 and released publicly in 2015 to optimize and improve the efficiency of RESTful APIs.
GraphQL is a powerful tool that allows clients to request exactly the data they need, no more and no less. It empowers front-end developers by providing a flexible and precise way to communicate with APIs.
- Execution Engine: GraphQL executes queries by leveraging a schema that defines the types of data and relationships between them.
- Data Query Language: It enables clients to query their API using a syntax that is intuitive and easy to understand.
Learn more about GraphQL: GraphQL Official Website
- With GraphQL, clients can request only the data they need, reducing the amount of data transferred over the network. This leads to faster and more efficient applications.
- Unlike REST, where you might need multiple endpoints to retrieve related data, GraphQL allows you to fetch all necessary data in a single request.
- GraphQL operates on a strongly typed schema, which provides clear definitions of the data structures, ensuring more predictable and reliable API interactions.
- GraphQL supports real-time updates through subscriptions, making it ideal for applications that require live data, such as chat apps or stock tickers.
While REST has been the traditional choice for building APIs, GraphQL offers several advantages:
| Feature | GraphQL | REST |
|---|---|---|
| Data Fetching | Single request for precisely the data needed | Multiple endpoints, potential over-fetching |
| Versioning | No versioning needed, evolve schema smoothly | Requires versioning, multiple versions can exist |
| Flexibility | High flexibility with queries | Limited flexibility, predefined responses |
| Real-time | Supports real-time updates via subscriptions | Requires additional protocols like WebSockets |
- Declarative Data Fetching: Clients can request specific data, making API responses predictable and efficient.
- Strongly Typed Schema: The schema acts as a contract between the client and server, ensuring consistency and reliability.
- Introspection: Clients can query the schema itself to understand the available data and operations.
- Hierarchical Queries: Data can be fetched in a nested, hierarchical structure, which mirrors the data's relationship in the backend.
- Mutations: GraphQL supports not only querying data but also modifying it through mutations.
Apollo Server is a community-driven, open-source GraphQL server that is compatible with any GraphQL schema. It is easy to set up and works seamlessly with various data sources.
npm install apollo-server graphql