Unable to Retrieve Blob Size from Response Without Consuming it

[ilshm]

I'm currently tackling a project that requires fetching the size of a Response associated with a request within middleware.

Here's what I've attempted so far:

import { Hono } from 'hono'
 
const app = new Hono()
 
// Middleware to log the response size
const responseSizeLogger = async (c, next) => {
  // Wrap the original `text` method
  const originalText = c.text.bind(c)
  c.text = (body, status = 200) => {
    const bodySize = Buffer.byteLength(body, 'utf8')
    console.log(`Response size: ${bodySize} bytes`)
    return originalText(body, status)
  }
 
  // Continue with the next middleware
  await next()
}
 
app.use('*', responseSizeLogger)
 
// Example route
app.get('/', (c) => c.text('Hello World!'))
 
export default app

This implementation works fine, but it has a complexity issue, and I'm unsure if interacting with .text() in middleware is acceptable.

When attempting console.log(c.res) in the middleware, it yields:

Response (14 bytes) {
  ok: true,
  url: "",
  status: 200,
  statusText: "",
  headers: Headers {},
  redirected: false,
  bodyUsed: false,
  Blob (14 bytes)
}

However, any attempts to access the blob size (or length) have been unsuccessful, resulting in either wiping the response body or returning undefined.

Could you please assist me with this issue :(