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What is GraphQL? How to use GraphQL?
What is GraphQL?
GraphQL is a query language for the API and a server-side runtime for executing queries. It gives clients the requested data and no extra information.
Why we need GraphQL?
GraphQL is really flexible for the following cases:
- GraphQL is an alternative to REST
- GraphQL is designed to make APIs fast, flexible, and developer-friendly
- GraphQL lets developers construct requests that pull data from multiple data sources in a single API call
- GraphQL gives API maintainers the flexibility to add or deprecate fields without impacting existing queries
Advantages of GraphQL:
- The GraphQL schema sets a single source of truth in a GraphQL application. It offers an organization a way to federate its entire API.
- GraphQL calls are handled in a single round trip. Clients get what they request with no overfetching.
- Strongly defined data types reduce miscommunication between the client and the server.
- GraphQL is introspective. A client can request a list of data types available. This is ideal for auto-generating documentation.
- GraphQL allows an application API to evolve without breaking existing queries.
- Many open source GraphQL extensions are available to offer features not available with REST APIs.
- GraphQL does not dictate a specific application architecture. It can be introduced on top of an existing REST API and can work with existing API management tools.
Disadvantages of GraphQL:
- GraphQL presents a learning curve for developers familiar with REST APIs.
- GraphQL shifts much of the work of a data query to the server side, which adds complexity for server developers.
- Depending on how it is implemented, GraphQL might require different API management strategies than REST APIs, particularly when considering rate limits and pricing.
- Caching is more complex than with REST.
- API maintainers have the additional task of writing maintainable GraphQL schema.