在 Node.js 中从网络流创建 blob

网络流创建 blob"/>

在 Node.js 中从网络流创建 blob

我正在尝试通过

ipfs-car

（使用网络流）打包 CAR 文件，然后将其作为文件在请求中发送，但我不确定在流式传输后如何将其存储在

Blob

中

WritableStream

。

我有这段代码

import { CAREncoderStream, createDirectoryEncoderStream } from 'ipfs-car'
import { WritableStream } from 'node:stream/web'

export const packCAR = async (files) => {
  const blockStream = createDirectoryEncoderStream(files)
  const carEncoderStream = new CAREncoderStream([])
  const outStream = new WritableStream()
  await blockStream.pipeThrough(carEncoderStream).pipeTo(outStream)
  const blob = new Blob(/* what do I put here? */)
}

我还没有发现有人这样做，我只看到了如何将

Blob

转换为流，所以我们将不胜感激:)

回答如下：

将 WritableStream 的内容存储到 Blob 中。这可以通过将 WritableStream 转换为 ReadableStream，然后将其转换为 ArrayBuffer，最后将 ArrayBuffer 存储到 Blob 来完成。

import { CAREncoderStream, createDirectoryEncoderStream } from 'ipfs-car'
import { WritableStream, ReadableStream } from 'node:stream/web'

export const packCAR = async (files) => {
  const blockStream = createDirectoryEncoderStream(files)
  const carEncoderStream = new CAREncoderStream([])
  const chunks = []
  const outStream = new WritableStream({
    write(chunk) {
      chunks.push(chunk)
    },
    close() {
      console.log('Stream is closed.')
    }
  })
  await blockStream.pipeThrough(carEncoderStream).pipeTo(outStream)
  const arrayBuffer = await new Blob(chunks).arrayBuffer()
  const blob = new Blob([arrayBuffer])
  return blob
}