KEQ-EXCEPTION
[](https://www.npmjs.com/package/keq-exception)
[](https://www.npmjs.com/package/keq-exception)
[](https://www.npmjs.com/package/keq-exception)
[](https://www.npmjs.com/package/keq-exception)
[](https://codecov.io/gh/keq-request/keq-exception)
[Document EN]: https://keq-request.github.io/guide/libraries/keq-exception
[Document CN]: https://keq-request.github.io/zh/guide/libraries/keq-exception
[**Document**][Document EN] | [**中文文档**][Document CN]
`Middleware` for throwing/catching exceptions. And it can control whether the exception trigger `retry`.
## Usage
```typescript
import { request } from "keq"
import {
throwException,
catchException,
RequestException,
} from "keq-exception"
request
.use(
catchException((err) => {
if (err instanceof RequestException && err.code === 401) {
context.redirect("/login")
return
}
throw err
})
)
// Callback will run after `await next()`.
// This way you can throw errors based on the response body.
.use(
throwException(async (ctx) => {
if (ctx.response && ctx.response.status >= 400) {
const body = await ctx.response.json()
throw new RequestException(ctx.response.status, body.message)
}
})
)
```
### RequestException(statusCode[, errorMessage[, retry]])
| **Parameter** | **Default** | **Description** |
| :------------ | :---------- | -------------------------------------------- |
| statusCode | - | Error code |
| message | `''` | Error message |
| retry | `true` | Whether the thrown error can trigger a retry |