3b7ed74d11
- examples to fix still
- error_extensions.md ResultExt example does not compile!
- trait ErrorExtensions is not implemented for ParseIntError
- dataloader
- requires sqlx to work. So we either "stub" it OR we rewrite them simpler to use a simple "faux" db library
65 lines
1.7 KiB
Markdown
65 lines
1.7 KiB
Markdown
# 快速开始
|
||
|
||
## 添加依赖
|
||
|
||
```toml
|
||
[dependencies]
|
||
async-graphql = "4.0"
|
||
async-graphql-actix-web = "4.0" # 如果你需要集成到Actix-web
|
||
async-graphql-warp = "4.0" # 如果你需要集成到Warp
|
||
async-graphql-tide = "4.0" # 如果你需要集成到Tide
|
||
```
|
||
|
||
## 写一个Schema
|
||
|
||
一个GraphQL的Schema包含一个必须的查询(Query)根对象，可选的变更(Mutation)根对象和可选的订阅(Subscription)根对象，这些对象类型都是用Rust语言的结构来描述它们，结构的字段对应GraphQL对象的字段。
|
||
|
||
Async-graphql实现了常用数据类型到GraphQL类型的映射，例如`i32`, `f64`, `Option<T>`, `Vec<T>`等。同时，你也能够[扩展这些基础类型](custom_scalars.md)，基础数据类型在GraphQL里面称为标量。
|
||
|
||
下面是一个简单的例子，我们只提供一个查询，返回`a`和`b`的和。
|
||
|
||
```rust
|
||
# extern crate async_graphql;
|
||
use async_graphql::*;
|
||
|
||
struct Query;
|
||
|
||
#[Object]
|
||
impl Query {
|
||
/// Returns the sum of a and b
|
||
async fn add(&self, a: i32, b: i32) -> i32 {
|
||
a + b
|
||
}
|
||
}
|
||
|
||
```
|
||
|
||
## 执行查询
|
||
|
||
在我们这个例子里面，只有Query，没有Mutation和Subscription，所以我们用`EmptyMutation`和`EmptySubscription`来创建Schema，然后调用`Schema::execute`来执行查询。
|
||
|
||
```rust
|
||
# extern crate async_graphql;
|
||
# use async_graphql::*;
|
||
#
|
||
# struct Query;
|
||
# #[Object]
|
||
# impl Query {
|
||
# async fn version(&self) -> &str { "1.0" }
|
||
# }
|
||
# async fn other() {
|
||
let schema = Schema::new(Query, EmptyMutation, EmptySubscription);
|
||
let res = schema.execute("{ add(a: 10, b: 20) }").await;
|
||
# }
|
||
```
|
||
|
||
## 把查询结果输出为JSON
|
||
|
||
```rust,ignore
|
||
let json = serde_json::to_string(&res);
|
||
```
|
||
|
||
## 和Web Server的集成
|
||
|
||
请参考https://github.com/async-graphql/examples。
|