111 lines
3.9 KiB
Python
111 lines
3.9 KiB
Python
"""File recursion example.
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Demonstration of iterating through a directory to interact with
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files.
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Example Usage:
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``$ python recursion_example.py``
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References:
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* https://docs.python.org/3/library/os.html
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List a directory
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================
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This function shows an example of displaying all files and
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folders within a single directory. From here you can further
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interact with individual files and folders or iterate recursively
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by calling the function on identified subdirectories.
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.. literalinclude:: ../sections/section_01/recursion_example.py
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:pyobject: list_directory
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List a directory recursively
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============================
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This function shows an example of displaying all files and
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folders within a all directories. You don't need to worry about
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additional function calls as the ``os.walk()`` method handles
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the recursion on subdirectories and your logic can focus on
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handling the processing of files. This sample shows a method of
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counting the number of files, subdirectories, and files ending in
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".py" as an example.
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.. literalinclude:: ../sections/section_01/recursion_example.py
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:pyobject: iterate_files
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"""
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import os
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"""
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Copyright 2019 Chapin Bryce
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Permission is hereby granted, free of charge, to any person
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obtaining a copy of this software and associated documentation
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files (the "Software"), to deal in the Software without
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restriction, including without limitation the rights to use, copy,
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modify, merge, publish, distribute, sublicense, and/or sell copies
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of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be
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included in all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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DEALINGS IN THE SOFTWARE.
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"""
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__author__ = 'Chapin Bryce'
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__date__ = 20190527
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__license__ = 'MIT Copyright 2019 Chapin Bryce'
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__desc__ = '''Sample script to iterate over a folder of files.'''
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__docs__ = [
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'https://docs.python.org/3/library/os.html'
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]
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def list_directory(path):
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"""List all file and folder entries in `path`."""
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print(f"Files and folders in '{os.path.abspath(path)}':")
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# Quick and easy method for listing items within a single
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# folder.
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for entry in os.listdir(path):
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# Print all entry names
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print(f"\t{entry}")
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def iterate_files(path):
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# Though `os.walk()` exposes a list of directories in the
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# current `root`, it is rarely used since we are generally
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# interested in the files found within the subdirectories.
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# For this reason, it is common to see `dirs` named `_`.
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# DO NOT NAME `dirs` as `dir` since `dir` is a reserved word!
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for root, dirs, files in os.walk(os.path.abspath(path)):
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# Both `dirs` and `files` are lists containing all entries
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# at the current `root`.
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for fentry in files:
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# To effectively reference a file, you should include
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# the below line which creates a full path reference
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# to the specific file, regardless of how nested it is
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file_entry = os.path.join(root, fentry)
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# We can then hand `file_entry` off to other functions.
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yield file_entry
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if __name__ == "__main__":
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abspath = os.path.abspath
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print(f"Listing {abspath('.')}")
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list_directory('.')
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print(f"\nRecurively counting files in {abspath('../../')}")
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num_py_files = 0
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for file_entry in iterate_files('../../'):
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if file_entry.endswith('.py'):
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num_py_files += 1
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print(f"\t{num_py_files} python files found "
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f"in {abspath('../../')}") |