Learn about GraphQL, how it works, and how to use it in this series of articles. Looking for documentation on how to build a GraphQL service? There are libraries to help you implement GraphQL in many different languages. For an in-depth learning experience with practical tutorials, visit the How to GraphQL fullstack tutorial website. We have also partnered with edX to create a free online course, Exploring GraphQL: A Query Language for APIs.
GraphQL 是一种 API 查询语言, 用于服务器端执行按已定义类型系统的查询. GraphQL 不与任何特定的数据库或存储引擎进行绑定, 而是由您的代码和数据支持.
通过定义类型和字段类型来创建 GraphQL 服务, 提供方法给每一个类型字段. 例如, 一个 GraphQL 服务, 告诉我们谁是登录用户(me
), 用户信息可能是像这样显示:
type Query { me: User } type User { id: ID name: String }
为每个字段类型定义的函数:
function Query_me(request) { return request.auth.user; } function User_name(user) { return user.getName(); }
Once a GraphQL service is running (typically at a URL on a web service), it can receive GraphQL queries to validate and execute. A received query is first checked to ensure it only refers to the types and fields defined, then runs the provided functions to produce a result.
示例查询请求:
{ me { name } }
可能处理得到的 JSON:
{ "me": { "name": "Luke Skywalker" } }
Learn more about GraphQL — the query language, type system, how the GraphQL service works, as well as best practices for using GraphQL in the articles written in this section; they help to solve common problems.