How can I access body in preHandler on form-data request & application/json request?

[biigpongsatorn]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Fastify version

4.x.x

Plugin version

No response

Node.js version

20.3.0

Operating system

macOS

Operating system version (i.e. 20.04, 11.3, 10)

13.6.1

Description

I was trying to validate the body before sending the request to upstream server. But I don't know how to read the body from the request.

And my proxy should be support application/json and multipart/form-data. So how can I access the body value from both type of requests?

Link to code that reproduces the bug

No response

Expected Behavior

preHandler: async (request) => {
     const contentType = request.headers['content-type']
     if (contentType === 'application/json') {
          // I want to access body data here
     } else if (contentType === 'multipart/form-data') {
          // I want to access body data here
     }
}

[biigpongsatorn]

Related to this PR

"fastify-reply-from" is not compatible with "fastify-multipart," so I will close this issue.