reproduce-flush.ts

import { serve } from '@hono/node-server'
import { Hono } from 'hono'

const app = new Hono()

app.get('/reproduce-flush', async (c) => {
  let transformController
  let bufferedChunks = ['chunk1', 'chunk2']

  const stream = new ReadableStream({
    start(controller) {
      controller.enqueue('initial data')
      controller.close()
    }
  })

  const transformStream = new TransformStream({
    start(controller) {
      transformController = controller

      // flushBufferedChunksをシミュレート
      const flushBufferedChunks = () => {
        bufferedChunks.forEach((chunk) => {
          try {
            controller.enqueue(chunk) // ここでERR_INVALID_STATEが発生
          } catch (error) {
            console.error('flushBufferedChunks error:', error.message)
          }
        })
      }

      // 遅延実行（Wakuの実装をシミュレート）
      setTimeout(flushBufferedChunks, 100)
    },

    transform(chunk, controller) {
      // 即座にストリームをクローズしてしまう
      controller.enqueue(chunk)
      controller.terminate() // または何らかの理由でクローズ
    }
  })

  const transformedStream = stream.pipeThrough(transformStream)
  return c.body(transformedStream, 200)
})

serve(
  {
    fetch: app.fetch,
    port: 3000
  },
  (info) => {
    console.log(`Server is running on http://localhost:${info.port}`)
  }
)