Write to a file in a Google Cloud Storage bucket by piping a Web Stream to stdin of a `gcloud alpha storage cp` process.

deno-cloud-storage-web-streams.ts

export const cloudStorageJsonLinesWriter = (url: string) => {
  // gcloud components install alpha
  const process = Deno.run({
    cmd: [
      'gcloud',
      'alpha',
      'storage',
      'cp',
      '-',
      url,
      '--cache-control=no-transform',
      '--content-encoding=gzip',
      '--content-type=application/x-ndjson',
      '--quiet',
    ],
    stdin: 'piped',
  })

  const stream = new TransformStream()

  stream.readable
    .pipeThrough(
      new TransformStream({
        transform(chunk, controller) {
          controller.enqueue(JSON.stringify(chunk))
          controller.enqueue('\n')
        },
      })
    )
    .pipeThrough(new TextEncoderStream())
    .pipeThrough(new CompressionStream('gzip'))
    .pipeTo(process.stdin!.writable)
    .finally(() => process.status())

  return stream.writable.getWriter()
}