How to delete all files in particular folder present in current directory sub-folders excluding a certain file?

Question

There are lots of posts where people asking how to delete files except ones, but my question is more specific. There are several folders named migrations in current directory's sub-folders, which contain __init__.py file and some more. How to delete all files except __init__.py in all sub-folders named migrations from current folder?

UPD: And is it possible to overwrite __init__.py with empty file?

Folder structure:

├── folder_1
│   ├── migrations
│   │   ├── 0001_initial.py
│   │   ├── __init__.py
│   │   └── __pycache__
│   │       ├── 0001_initial.cpython-35.pyc
│   │       └── __init__.cpython-35.pyc
├── folder_2
│   ├── migrations
│   │   ├── 0001_initial.py
│   │   ├── __init__.py
│   │   └── __pycache__
│   │       ├── 0001_initial.cpython-35.pyc
│   │       └── __init__.cpython-35.pyc
├── folder_3
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   │   ├── 0001_initial.py
│   │   ├── __init__.py
│   │   └── __pycache__
│   │       ├── 0001_initial.cpython-35.pyc
│   │       └── __init__.cpython-35.pyc

Answer 1

With find:

find . -path '*/migrations/__init__.py' -exec truncate -s 0 {} + -o -path '*/migrations/*' -delete

This runs find in the current directory (.), and:

• for anything matching migrations/__init__.py, it will run the truncate command. truncate -s 0 <file> reduces the file to size 0 (empty);
• failing that match, for anything matching migrations/*, it will delete it;
• the * in -path matches / unlike the * in bash.

Example:

$ tree                                                                                                                                   
.
├── folder_1
│   └── migrations
│       ├── 0001_initial.py
│       ├── __init__.py
│       └── __pycache__
│           ├── 0001_initial.cpython-35.pyc
│           └── __init__.cpython-35.pyc
├── folder_2
│   └── migrations
│       ├── 0001_initial.py
│       ├── __init__.py
│       └── __pycache__
│           ├── 0001_initial.cpython-35.pyc
│           └── __init__.cpython-35.pyc
└── folder_3
    ├── admin.py
    ├── apps.py
    ├── __init__.py
    └── migrations
        ├── 0001_initial.py
        ├── __init__.py
        └── __pycache__
            ├── 0001_initial.cpython-35.pyc
            └── __init__.cpython-35.pyc

9 directories, 15 files
$ find . -path '*/migrations/__init__.py' -exec truncate -s 0 {} + -o -path '*/migrations/*' -delete                
$ tree                                                                                              
.
├── folder_1
│   └── migrations
│       └── __init__.py
├── folder_2
│   └── migrations
│       └── __init__.py
└── folder_3
    ├── admin.py
    ├── apps.py
    ├── __init__.py
    └── migrations
        └── __init__.py

6 directories, 6 files

$ wc -l */migrations/__init__.py
0 folder_1/migrations/__init__.py
0 folder_2/migrations/__init__.py
0 folder_3/migrations/__init__.py
0 total

Answer 2

Create a .py file, edit the path (directory that you will work), and compile it (python3).

• code: delete all files on 'path' except 'target_file' inside 'target_folder', that are just clear(empty).

import os, sys
path='/home/vitor/Desktop/teste/'
target_folder='migrations'
target_file='__init__.py'

for directory, subdirs, files in os.walk(path):
    for file_name in files:
        folder_name=os.path.split(os.path.abspath(directory))[-1]
        if(folder_name==target_folder and file_name==target_file):
            open(directory+'/'+file_name, 'w').close()
        else:
            os.remove(directory+'/'+file_name)

Answer 3

Here is a simpler command. I know some one already answered the question, but these commands should be simpler and unique. Try them to see if they work.

To remove every subfolder and file except __init__.py and displays which files have been deleted, try the following commands:

rm -rfv ./*/migrations/!(__init__.py)

To make a empty file, just add the following command in addition:

> ./*/migrations/__init__.py

The above command is just like writing empty data to a file like as follows:

/dev/null > ./*/migrations/__init__.py

Note

All these commands execute from current directory .

Precaution

Please make a backup before you try any of the commands. No one is 100% perfect in this world.