add sync-missing-metadata command with docs, resolves #25

README.md

@@ -203,6 +203,8 @@ and less common features:
 
 ![Import existing media into TubeSync](https://github.com/meeb/tubesync/blob/main/docs/import-existing-media.md)
 
+![Sync or create missing metadata files](https://github.com/meeb/tubesync/blob/main/docs/create-missing-metadata.md)
+
 
 # Warnings
 

docs/create-missing-metadata.md

@@ -0,0 +1,37 @@
+# TubeSync
+
+## Advanced usage guide - creating missing metadata
+
+This is a new feature in v0.9 of TubeSync and later. It allows you to create or
+re-create missing metadata in your TubeSync download directories for missing `nfo`
+files and thumbnails.
+
+If you add a source with "write NFO files" or "copy thumbnails" disabled, download
+some media and then update the source to write NFO files or copy thumbnails then
+TubeSync will not automatically retroactively attempt to copy or create your missing
+metadata files. You can use a special one-off command to manually write missing
+metadata files to the correct locations.
+
+## Requirements
+
+You have added a source without metadata writing enabled, downloaded some media, then
+updated the source to enable metadata writing.
+
+## Steps
+
+### 1. Run the batch metadata sync command
+
+Execute the following Django command:
+
+`./manage.py sync-missing-metadata`
+
+When deploying TubeSync inside a container, you can execute this with:
+
+`docker exec -ti tubesync python3 /app/manage.py sync-missing-metadata`
+
+This command will log what its doing to the terminal when you run it.
+
+Internally, this command loops over all your sources which have been saved with
+"write NFO files" or "copy thumbnails" enabled. Then, loops over all media saved to
+that source and confirms that the appropriate thumbnail files have been copied over and
+the NFO file has been written if enabled.

tubesync/sync/management/commands/sync-missing-metadata.py

@@ -0,0 +1,34 @@
+import os
+from shutil import copyfile
+from django.core.management.base import BaseCommand, CommandError
+from django.db.models import Q
+from common.logger import log
+from sync.models import Source, Media
+from sync.utils import write_text_file
+
+
+class Command(BaseCommand):
+
+    help = 'Syncs missing metadata (such as nfo files) if source settings are updated'
+
+    def handle(self, *args, **options):
+        log.info('Syncing missing metadata...')
+        sources = Source.objects.filter(Q(copy_thumbnails=True) | Q(write_nfo=True))
+        for source in sources.order_by('name'):
+            log.info(f'Finding media for source: {source}')
+            for item in Media.objects.filter(source=source, downloaded=True):
+                log.info(f'Checking media for missing metadata: {source} / {item}')
+                thumbpath = item.thumbpath
+                if not thumbpath.is_file():
+                    if item.thumb:
+                        log.info(f'Copying missing thumbnail from: {item.thumb.path} '
+                                 f'to: {thumbpath}')
+                        copyfile(item.thumb.path, thumbpath)
+                    else:
+                        log.error(f'Tried to copy missing thumbnail for {item} but '
+                                  f'the thumbnail has not been downloaded')
+                nfopath = item.nfopath
+                if not nfopath.is_file():
+                    log.info(f'Writing missing NFO file: {nfopath}')
+                    write_text_file(nfopath, item.nfoxml)
+        log.info('Done')