Elysia.js

Appearance

On this page

Body Parser ​

Like Express, body-parser is a function to parse body of an incoming request.

By default, Elysia will parse the body with content-type of:

  • text/plain
  • application/json
  • multipart/form-data

And assign the value to Context.body.

Then you can get body from body as:

typescript
import { Elysia } from 'elysia'

new Elysia()
    .post("/add", ({ body }) => {
        console.log(body)
    })
    .listen(8080)

import { Elysia } from 'elysia'

new Elysia()
    .post("/add", ({ body }) => {
        console.log(body)
    })
    .listen(8080)

Custom body parser ​

If you want to support more content-type, you can use onParse:

typescript
new Elysia()
    .onParse(({ request }, contentType) => {
        if (contentType === 'application/custom-type')
            return request.text()
    })

new Elysia()
    .onParse(({ request }, contentType) => {
        if (contentType === 'application/custom-type')
            return request.text()
    })

The returned value will be assigned to Context.body, otherwise, Elysia will iterate more parser functions assigned by onParse until either body is assigned or all parsers are executed.

You can also use request to take advantage and add custom behavior for parsing the body.

For example, parsing GraphQL on a specific path:

typescript
 app
    .onParse(({ request }, contentType) => {
        if (
            path === getPath(request.url) &&
            contentType === 'application/json'
        )
            return request.text()
    })

 app
    .onParse(({ request }, contentType) => {
        if (
            path === getPath(request.url) &&
            contentType === 'application/json'
        )
            return request.text()
    })