如何在Google Pub / Sub（GCP）中发布和订阅.pdf文件

Question

在下面的代码中，大的.pdf文件被分成几页，然后上传到存储桶中，并同时排队到pubsub中

    def publish_messages(project_id, topic_id, enqueue_file):
    
        publisher = pubsub_v1.PublisherClient()
        topic_path = publisher.topic_path(project_id, topic_id)
    
        data = enqueue_file
            # Data must be a bytestring
        data = data.encode("utf-8")
            # When you publish a message, the client returns a future.
        future = publisher.publish(topic_path, data=data)
        print(future.result())
    
        print(enqueue_file + "has been enqueued to Pub/Sub.")
    
    
    def upload_local_directory_to_gcs(local_path, bucket, gcs_path):
            assert os.path.isdir(local_path)
            for local_file in glob.glob(local_path + '/**'):
                if not os.path.isfile(local_file):
                    continue
                remote_path = os.path.join(gcs_path, local_file[1 + len(local_path) :])
                storage_client = storage.Client()
                buck = storage_client.bucket(bucket)
                blob = buck.blob(remote_path)
                blob.upload_from_filename(local_file)
                print("Uploaded " + local_file + " to gs bucket " + bucket)
                publish_messages("Project1", "my-topic", local_file)

我使用以下代码接收消息

def receive_messages(project_id, subscription_id , timeout=None):
    from concurrent.futures import TimeoutError
    from google.cloud import pubsub_v1

    subscriber = pubsub_v1.SubscriberClient()
    subscription_path = subscriber.subscription_path(project_id, subscription_id)

    def callback(message):
        print("Received message: {}".format(message))
        message.ack()

    streaming_pull_future = subscriber.subscribe(subscription_path, callback=callback)
    print("Listening for messages on {}..\n".format(subscription_path))
    
    with subscriber:
        try:
            streaming_pull_future.result(timeout=timeout)
        except TimeoutError:
            streaming_pull_future.cancel()

if __name__ == "__main__":
    receive_messages("Project1", "my-sub")

但是当我收到消息时，我只会得到字符串数据。

Received message: Message {
  data: b'/tmp/doc_pages/document-page17.pdf'
  ordering_key: ''
  attributes: {}
}

我的想法是获取pdf文件并使用Vision API执行一些OCR操作。是否可以获取pdf文件本身？还有其他方法请告诉我。

谢谢！