chunkedfile

ChunkedFile

A file handle that groups subsequence writes together and periodically writes them as separate files. Useful for file systems like GCS FUSE that do not support file appending. Pathlib can be patched to replace files opened in append mode with chunked files, so external libraries need not be changed.

Usage

Using ChunkedFile:

import time
import chunkedfile

# Write chunks up to every 10 minutes.
with chunkedfile.ChunkedFile('filename.txt', 600) as f:

  # The first chunk will be written on the first write after the sleep.
  f.write('Lorem\n')
  time.sleep(1000)
  f.write('Ipsum\n')

  # The last chunk is automatically written when the file is closed.
  f.write('Dolor\n')
  f.write('Sit\n')

# The directory now contains two files:
# - filename.txt-1-20210904T130400
# - filename.txt-2-20210904T132100

Using pathlib.Path:

import time
import pathlib
import chunkedfile

# Path objects opened in append mode will be replaced by chunked files.
chunkedfile.patch_pathlib_append(600)

# Write chunks up to every 10 minutes.
with pathlib.Path('filename.txt').open('a') as f:

  # The first chunk will be written during the sleep command.
  f.write('Lorem\n')
  f.write('Ipsum\n')
  time.sleep(1000)

  # The last chunk is automatically written when the file is closed.
  f.write('Dolor\n')
  f.write('Sit\n')

# The directory now contains two files:
# - filename.txt-1-20210904T130400
# - filename.txt-2-20210904T132100