Troubleshooting Common Issues in Typestack – Routing Controllers

Question: how to get raw request body

An effective resolution to the issue can be reached by introducing specialized middleware.

// RawBodyMiddleware.ts
import { Request, Response } from 'express';

const RawBodyMiddleware = (req: Request, res: Response, next: () => void) => {
  const body = []
  req.on('data', chunk => {
    body.push(chunk)
  })
  req.on('end', () => {
    const rawBody = Buffer.concat(body)
    req['rawBody'] = rawBody
    switch (req.header('content-type')) {
      case 'application/json':
        req.body = JSON.parse(rawBody.toString())
        break
      // add more body parsing if needs be
      default:
    }
    next()
  })
  req.on('error', () => {
    res.sendStatus(400)
  })
}

export default RawBodyMiddleware

To ensure the endpoint requiring raw body access is handled properly, incorporate middleware within your controller and then utilize the @Req() decorator to obtain information from the request’s raw body property.

import { Request, Response } from 'express';
import { Req, UseBefore } from 'routing-controllers';
import RawBodyMiddleware from '../middlewares/RawBodyMiddleware'

@Post('/myendpoint')
@UseBefore(RawBodyMiddleware)
public myEndpoint(@Req() request: Request) {
   const rawBody = request.rawBody
   const asString = rawBody.toString()

   const jsonBody = request.body
}

Validate array in Body decorator

To validate an array in the body of a request using the Routing Controllers library, you can use the @Body decorator and the @IsArray decorator from the class-validator library.

Here’s an example of how you can use these decorators to validate an array in the body of a request:

import { Body, JsonController, Post } from 'routing-controllers';
import { IsArray } from 'class-validator';

class MyBody {
  @IsArray()
  items: string[];
}

@JsonController()
class MyController {
  @Post('/items')
  create(@Body() body: MyBody) {
    // body.items is guaranteed to be an array of strings at this point
  }
}

In this example, the @IsArray decorator is used to validate that the items field in the request body is an array. If the items field is not an array, the validation will fail and an error will be returned.

You can also use the @IsArray decorator to validate that the array contains elements of a specific type, by specifying the type as a generic argument to the decorator. For example:

import { Body, JsonController, Post } from 'routing-controllers';
import { IsArray } from 'class-validator';

class MyBody {
  @IsArray()
  items: number[];
}

@JsonController()
class MyController {
  @Post('/items')
  create(@Body() body: MyBody) {
    // body.items is guaranteed to be an array of numbers at this point
  }
}

This will validate that the items field is an array of numbers, and will fail the validation if any of the elements in the array are not numbers.

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