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Python: read file(BinaryIO) multiple time
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Recently, I need to read BinaryIO object multiple time when handling Minio file.

solution : `seek(0)`
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The reason is that the cursor of BinaryIO object will stay at the end of the file after reading it. So, we need to reset the cursor by seek(0).

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

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

Read `UploadFile` object multiple time in `FastAPI`
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Because UploadFile object in FastAPI also encapsulates BinaryIO object. We can also reset the cursor by seek(0).

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