How to intercept requests to files in static folder (e.g. public) with middleware?

[cmdcolin]

background

I have a application that unzips static gzip files on the client side. Specifically, .gz files are actually "bgzip" files, and we do HTTP Range requests for parts of these files, and unzip the chunk client side, and this breaks when servers add Content-Encoding:gzip

what i tried

I tried to add a middleware for the rsbuild config but it doesn't seem to intercept the requests for static files

was trying something like this but it wasn't getting to my console.log for the middleware for the requests

import { IncomingMessage, ServerResponse } from 'http'

const { defineConfig } = require('@rsbuild/core')
module.exports = defineConfig({
  dev: {
    setupMiddlewares: [
      (middlewares, server) => {
        middlewares.push((req: IncomingMessage, res: ServerResponse, next) => {
          console.log(
            'before',req.url,
            req.headers,
            res.getHeader('Content-Encoding'),
          )
          res.removeHeader('Content-Encoding')
          console.log('after', res.getHeader('Content-Encoding'))
          next()
        })
      },
    ],
  },
})

other solutions considered

1. modify rsbuild to not respond with the Content-Encoding:gzip by making a PR to rsbuild
2. not use the .gz for my bgzip files...but this is very laborious as it is very entrenched in my field

[cmdcolin]

I found a workaround where I created a custom express server. Looks like the following:

import { createRsbuild } from '@rsbuild/core'
import express from 'express'
import serveStatic from 'serve-static'

async function startDevServer() {
  // Init Rsbuild
  const rsbuild = await createRsbuild({
    rsbuildConfig: {
      server: {
        htmlFallback: false, // useful for my use case, not strictly needed to pass custom rsbuildConfig otherwise
      },
    },
  })

  const app = express()

  // Create Rsbuild DevServer instance
  const rsbuildServer = await rsbuild.createDevServer()

  // serveStatic must be before Rsbuild's middlewares, it avoids issue where
  // Rsbuild adds Content-Encoding:gzip on bgzip files (files ending in .gz)
  // causing errors with tabix et al.
  app.use(serveStatic('public'))

  // Apply Rsbuild’s built-in middlewares
  app.use(rsbuildServer.middlewares)
  console.log(rsbuildServer.middlewares)

  const httpServer = app.listen(rsbuildServer.port, async () => {
    // Notify Rsbuild that the custom server has started
    await rsbuildServer.afterListen()
  })

  rsbuildServer.connectWebSocket({ server: httpServer })
}

startDevServer()