Locate and remove unreferenced media files.

check_media_files.py

#!/usr/bin/env python

"""
Locate and remove unreferenced media files.

Expects DJANGO_SETTINGS_MODULE to be set in the environment.

"""

import collections
import itertools
import os.path

import django
from django.apps import apps
from django.db import models
from django.db.migrations.serializer import DeconstructableSerializer

django.setup()  # noqa


def storage_key(field):
    return DeconstructableSerializer(field.storage).serialize()[0]


def enumerate_database(field):
    objects = field.model._base_manager
    if field.blank:
        objects = objects.exclude(**{field.name: ''})
    return objects.values_list(field.name, flat=True)


def enumerate_storage(storage, root=''):
    directories, files = storage.listdir(root)
    print('directories ' + root)
    print(directories)
    print('files' + root)
    print(files)
    print()
    for directory in directories:
        yield from enumerate_storage(storage, os.path.join(root, directory))
    for file in files:
        yield os.path.join(root, file)


file_fields = [
    field
    for model in apps.get_models()
    for field in model._meta.get_fields()
    if isinstance(field, models.FileField)
]


for storage_repr, fields in itertools.groupby(file_fields, storage_key):
    fields = list(fields)
    storage = fields[0].storage

    database_files = collections.Counter()
    for field in fields:
        database_files.update(enumerate_database(field))

    storage_files = list(enumerate_storage(storage))

    print("Multiple references")
    print("-------------------")
    print()

    for filepath, count in database_files.most_common():
        if count < 2:
            break
        print(count, filepath)

    print()

    print("Missing files")
    print("-------------")
    print()

    for filepath in set(database_files) - set(storage_files):
        print(filepath)

    print()

    print("Unreferenced files")
    print("------------------")
    print()

    for filepath in set(storage_files) - set(database_files):
        print(filepath)

    print()