Fastify inject method instead of fetch or axios

[officefish]

Prerequisites

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🚀 Feature Proposal

May be there is some way to accept fastify instance to NextRequest, then got it from getServerSideProps context, save it on page params and then use fastify.inject instead of fetch or axios?

I suppose it should be faster than ku_universal, axois and other libraries calls, but do not exactly understand how to pass fastify instance in render function.

I have an idea to extends RawRequest interface like

declare module 'fastify' {
    interface RawRequest {
        server: FastifyInstance
    }
} 

then give instance in gccp objects requests like :

 server.next(`/log-in`, async (app:NextServer, req:FastifyRequest, reply:FastifyReply) => {   
        // here we potentialy can accept fastify instance to req.raw
        raw.req.server = server
        await app.render(req.raw, reply.raw, '/log-in')
        reply.hijack()
})

and finally got ot from props

export const getServerSideProps: GetServerSideProps = async (context) => {
  const data = {server: context.req.server}
  return { props: { data } }
}

But unfortunatly there is no RawRequest interface in Fastify types.

[mcollina]

I would recommend to implement it in JavaScript and figure out what's missing in types afterwards.

[officefish]

I found a way to forward fastify instance with Incoming Message but got some undefined behavior when trying to get fastify instance in next getter method.

import { IncomingMessage } from "http"
 declare module 'http' {
     interface IncomingMessage {
         server?: FastifyInstance
 }
 }

async function routes(server:FastifyInstance)  {

    server.next(`/log-in`, async (app:NextServer, req:FastifyRequest, reply:FastifyReply) => {   
        req.raw.server = req.server
        await app.render(req.raw, reply.raw, '/log-in', {})
        reply.hijack()
    })
    
}

It will be great if plugin iteslf would be able decorate fastify instance for NextRequest when it nessecary. For example like that:

server.next('/home', { forwardFastify: true} )
or

server.nextWithFastify('/home')