Python: 重複讀取檔案(BinaryIO)
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剛好最近處裡讀取 Minio 檔案時，需要重複讀取 BinaryIO 物件但是發現第二次讀取時，檔案內容是空的

solution : `seek(0)`
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原因: BinaryIO 物件的 cursor 會在讀取完畢後停留在檔案的最後一個位置所以透過 seek(0) 來重設 cursor

f = open(f)
content = f.read()

f.seek(0) # need to reset cursor !!!!
content = f.read()

多次讀取 `FastAPI` 中的 `UploadFile` 物件
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因為 FastAPI 中的 UploadFile 物件內又封裝了 BinaryIO 物件同樣也可以透過 seek(0) 來重設 cursor

from fastapi import FastAPI, UploadFile, status

def file_service(upload_file: UploadFile):
  content = upload_file.file.read() # first read
  another_file_service(upload_file)
  return status.HTTP_200_OK

def another_file_service(upload_file: UploadFile):
  upload_file.file.seek(0) # need to reset cursor !!!!
  content = upload_file.file.read() # third read