fix: management commands & migrations fix

- Add `__init__.py` under `VIM/apps` directory to fix pylint error: `No name 'apps' in module 'VIM' Pylint(E0611:no-name-in-module)`;
- Adjust importing order in all management commands;
- In `download_imgs.py`: (1) remove class `ImageDownloader` and place all methods into `Command` class; (2) change constants into upper case; (3) add `timeout` for `requests.get`; (4) change general `Exception` into specific exception types such as `requests.RequestException` and `IOError`; (5) change all `print()` into `self.stdout.write` and `self.stderr.write`;
- In `import_instruments.py`, change relative image path into absolute path;
- Recover migrations file; create an additional file for thumbnail field;

Refs: #138

web-app/django/VIM/apps/instruments/management/commands/download_imgs.py

@@ -1,35 +1,50 @@
+"""This module downloads images from the web and creates thumbnails for the VIM instruments."""
+
 import csv
 import os
+from io import BytesIO
 import requests
 from PIL import Image
-from io import BytesIO
 from django.core.management.base import BaseCommand
 
 
-class ImageDownloader:
-    def __init__(self, user_agent, output_dir):
-        self.headers = {"User-Agent": user_agent}
-        self.original_img_dir = os.path.join(output_dir, "original")
-        self.thumbnail_dir = os.path.join(output_dir, "thumbnail")
+class Command(BaseCommand):
+    """Django management command to download images and create thumbnails for instruments."""
+
+    USER_AGENT = "UMIL/0.1.0 (https://vim.simssa.ca/; https://ddmal.music.mcgill.ca/)"
+    OUTPUT_DIR = "VIM/apps/instruments/static/instruments/images/instrument_imgs"
+    CSV_PATH = "startup_data/vim_instruments_with_images-15sept.csv"
+
+    help = "Download images and create thumbnails for instruments"
+
+    def __init__(self):
+        super().__init__()
+        self.headers = {"User-Agent": self.USER_AGENT}
+        self.original_img_dir = os.path.join(self.OUTPUT_DIR, "original")
+        self.thumbnail_dir = os.path.join(self.OUTPUT_DIR, "thumbnail")
         os.makedirs(self.original_img_dir, exist_ok=True)
         os.makedirs(self.thumbnail_dir, exist_ok=True)
 
     def download_image_as_png(self, url, save_path):
+        """Download an image from a URL and save it as a PNG file."""
         try:
-            response = requests.get(url, stream=True, headers=self.headers)
+            response = requests.get(url, stream=True, headers=self.headers, timeout=10)
             response.raise_for_status()  # Raise an HTTPError for bad responses
-            self._save_image_as_png(response.content, save_path)
-            print(f"Downloaded {url} to {save_path}")
+            self._save_image_as_png(response.content, url, save_path)
         except requests.RequestException as e:
-            print(f"Failed to download {url}: {e}")
-        except Exception as e:
-            print(f"Error processing {url}: {e}")
+            self.stderr.write(f"Failed to download image from {url}: {e}")
 
-    def _save_image_as_png(self, img_content, save_path):
-        img = Image.open(BytesIO(img_content))
-        img.save(save_path, "PNG")
+    def _save_image_as_png(self, img_content, url, save_path):
+        """Save image content as a PNG file."""
+        try:
+            img = Image.open(BytesIO(img_content))
+            img.save(save_path, "PNG")
+            self.stdout.write(f"Saved image at {save_path}")
+        except IOError as e:
+            self.stderr.write(f"Failed to save image from {url}: {e}")
 
     def create_thumbnail(self, image_path, thumbnail_path, compression_ratio=0.35):
+        """Create a thumbnail of an image."""
         try:
             with Image.open(image_path) as original_img:
                 new_size = (
@@ -38,11 +53,12 @@ def create_thumbnail(self, image_path, thumbnail_path, compression_ratio=0.35):
                 )
                 original_img.thumbnail(new_size)
                 original_img.save(thumbnail_path, "PNG")
-                print(f"Created thumbnail for {image_path}")
-        except Exception as e:
-            print(f"Error creating thumbnail for {image_path}: {e}")
+            self.stdout.write(f"Created thumbnail at {thumbnail_path}")
+        except IOError as e:
+            self.stderr.write(f"Failed to create thumbnail for {image_path}: {e}")
 
     def process_images(self, csv_file_path):
+        """Process images from a CSV file."""
         with open(csv_file_path, encoding="utf-8-sig") as csvfile:
             reader = csv.DictReader(csvfile)
             for row in reader:
@@ -58,20 +74,10 @@ def process_images(self, csv_file_path):
                 if not os.path.exists(save_path_png):
                     self.download_image_as_png(image_url, save_path_png)
 
-                if not os.path.exists(thumbnail_path):
+                if not os.path.exists(thumbnail_path) and os.path.exists(save_path_png):
                     self.create_thumbnail(save_path_png, thumbnail_path)
 
-
-class Command(BaseCommand):
-    help = "Download images and create thumbnails for instruments"
-
     def handle(self, *args, **options):
-        user_agent = (
-            "UMIL/0.1.0 (https://vim.simssa.ca/; https://ddmal.music.mcgill.ca/)"
-        )
-        output_dir = "VIM/apps/instruments/static/instruments/images/instrument_imgs"
-        csv_file_path = "startup_data/vim_instruments_with_images-15sept.csv"
-
-        downloader = ImageDownloader(user_agent, output_dir)
-        downloader.process_images(csv_file_path)
-        print("Images downloaded and thumbnails created")
+        """Handle the command."""
+        self.process_images(self.CSV_PATH)
+        self.stdout.write("Images downloaded and thumbnails created")

web-app/django/VIM/apps/instruments/management/commands/import_instruments.py

@@ -1,8 +1,12 @@
+"""This module imports instrument objects from Wikidata for the VIM project."""
+
 import csv
+import os
 from typing import Optional
 import requests
 from django.core.management.base import BaseCommand
 from django.db import transaction
+from django.conf import settings
 from VIM.apps.instruments.models import Instrument, InstrumentName, Language, AVResource
 
 
@@ -17,6 +21,10 @@ class Command(BaseCommand):
 
     help = "Imports instrument objects"
 
+    def __init__(self):
+        super().__init__()
+        self.language_map: dict[str, Language] = {}
+
     def parse_instrument_data(
         self, instrument_id: str, instrument_data: dict
     ) -> dict[str, str | dict[str, str]]:
@@ -128,6 +136,9 @@ def handle(self, *args, **options) -> None:
             reader = csv.DictReader(csvfile)
             instrument_list: list[dict] = list(reader)
         self.language_map = Language.objects.in_bulk(field_name="wikidata_code")
+        img_dir = os.path.join(
+            settings.STATIC_URL, "instruments", "images", "instrument_imgs"
+        )
         with transaction.atomic():
             for ins_i in range(0, len(instrument_list), 50):
                 ins_ids_subset: list[str] = [
@@ -136,9 +147,12 @@ def handle(self, *args, **options) -> None:
                 ]
                 ins_data: list[dict] = self.get_instrument_data(ins_ids_subset)
                 for instrument_attrs, ins_id in zip(ins_data, ins_ids_subset):
-                    img_dir = "../../static/instruments/images/instrument_imgs"
-                    original_img_path = f"{img_dir}/original/{ins_id}.png"
-                    thumbnail_img_path = f"{img_dir}/thumbnail/{ins_id}.png"
+                    original_img_path = os.path.join(
+                        img_dir, "original", f"{ins_id}.png"
+                    )
+                    thumbnail_img_path = os.path.join(
+                        img_dir, "thumbnail", f"{ins_id}.png"
+                    )
                     self.create_database_objects(
                         instrument_attrs, original_img_path, thumbnail_img_path
                     )

web-app/django/VIM/apps/instruments/management/commands/import_languages.py

@@ -1,3 +1,5 @@
+"""This module imports possible languages for instrument names from Wikidata."""
+
 from django.core.management.base import BaseCommand
 from VIM.apps.instruments.models import Language
 

web-app/django/VIM/apps/instruments/management/commands/index_data.py

@@ -1,8 +1,10 @@
+"""This module indexes instrument data in the database in Solr."""
+
 from django.core.management.base import BaseCommand
 from django.db.models import F, CharField, Value as V
 from django.db.models.functions import Concat, Left
-from VIM.apps.instruments.models import Instrument
 import requests
+from VIM.apps.instruments.models import Instrument
 
 
 class Command(BaseCommand):
@@ -43,6 +45,7 @@ def handle(self, *args, **options):
         )
 
     def build_hbs_label_map(self):
+        """Build a mapping of Hornbostel-Sachs classification codes to labels."""
         # For now, we just want the names in English and French of the first category of
         # the Hornbostel-Sachs classification.
         eng_name_mapping = {

web-app/django/VIM/apps/instruments/migrations/0001_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 4.2.5 on 2024-08-12 14:23
+# Generated by Django 4.2.5 on 2023-09-27 18:47
 
 from django.db import migrations, models
 import django.db.models.deletion
@@ -102,16 +102,6 @@ class Migration(migrations.Migration):
                         to="instruments.avresource",
                     ),
                 ),
-                (
-                    "thumbnail",
-                    models.ForeignKey(
-                        blank=True,
-                        null=True,
-                        on_delete=django.db.models.deletion.PROTECT,
-                        related_name="thumbnail_of",
-                        to="instruments.avresource",
-                    ),
-                ),
             ],
         ),
         migrations.CreateModel(

web-app/django/VIM/apps/instruments/migrations/0002_instrument_thumbnail.py

@@ -0,0 +1,24 @@
+# Generated by Django 4.2.5 on 2024-08-13 14:23
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("instruments", "0001_initial"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="instrument",
+            name="thumbnail",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.PROTECT,
+                related_name="thumbnail_of",
+                to="instruments.avresource",
+            ),
+        ),
+    ]