feat(Proof): generate image thumbnail (size 400) on create (#486)

config/settings.py

@@ -164,6 +164,13 @@
 CORS_ALLOW_CREDENTIALS = True
 
 
+# Pillow
+# https://pillow.readthedocs.io/
+# ------------------------------------------------------------------------------
+
+THUMBNAIL_SIZE = (400, 400)
+
+
 # Django REST Framework (DRF) & django-filters & drf-spectacular
 # https://www.django-rest-framework.org/
 # https://django-filter.readthedocs.io/

open_prices/api/proofs/tests.py

@@ -173,6 +173,8 @@ def test_proof_create(self):
             headers={"Authorization": f"Bearer {self.user_session.token}"},
         )
         self.assertEqual(response.status_code, 201)
+        self.assertTrue(response.data["file_path"] is not None)
+        self.assertTrue(response.data["image_thumb_path"] is None)  # .bin
         self.assertEqual(response.data["currency"], "EUR")
         self.assertEqual(response.data["price_count"], 0)  # ignored
         self.assertEqual(response.data["owner"], self.user_session.user.user_id)

open_prices/api/proofs/views.py

@@ -64,10 +64,11 @@ def upload(self, request: Request) -> Response:
                 {"file": ["This field is required."]},
                 status=status.HTTP_400_BAD_REQUEST,
             )
-        file_path, mimetype = store_file(request.data.get("file"))
+        file_path, mimetype, image_thumb_path = store_file(request.data.get("file"))
         proof_create_data = {
             "file_path": file_path,
             "mimetype": mimetype,
+            "image_thumb_path": image_thumb_path,
             **{key: request.data.get(key) for key in Proof.CREATE_FIELDS},
         }
         # validate
@@ -76,6 +77,9 @@ def upload(self, request: Request) -> Response:
         # get source
         self.source = self.request.GET.get("app_name", "API")
         # save
-        proof = serializer.save(owner=self.request.user.user_id, source=self.source)
+        proof = serializer.save(
+            owner=self.request.user.user_id,
+            source=self.source,
+        )
         # return full proof
         return Response(ProofFullSerializer(proof).data, status=status.HTTP_201_CREATED)

open_prices/proofs/migrations/0004_proof_image_thumb_path_alter_proof_file_path.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.1 on 2024-10-02 07:26
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("proofs", "0003_alter_proof_type"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="proof",
+            name="image_thumb_path",
+            field=models.CharField(blank=True, null=True),
+        ),
+        migrations.AlterField(
+            model_name="proof",
+            name="file_path",
+            field=models.CharField(blank=True, null=True),
+        ),
+    ]

open_prices/proofs/models.py

@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.core.validators import ValidationError
 from django.db import models
 from django.db.models import Count
@@ -20,7 +21,7 @@ def with_stats(self):
 
 
 class Proof(models.Model):
-    FILE_FIELDS = ["file_path", "mimetype"]
+    FILE_FIELDS = ["file_path", "mimetype", "image_thumb_path"]
     UPDATE_FIELDS = ["type", "currency", "date"]
     CREATE_FIELDS = UPDATE_FIELDS + ["location_osm_id", "location_osm_type"]
     DUPLICATE_PRICE_FIELDS = [
@@ -30,10 +31,12 @@ class Proof(models.Model):
         "currency",
     ]  # "owner"
 
-    file_path = models.CharField()
+    file_path = models.CharField(blank=True, null=True)
     mimetype = models.CharField(blank=True, null=True)
     type = models.CharField(max_length=20, choices=proof_constants.TYPE_CHOICES)
 
+    image_thumb_path = models.CharField(blank=True, null=True)
+
     location_osm_id = models.PositiveBigIntegerField(blank=True, null=True)
     location_osm_type = models.CharField(
         max_length=10,
@@ -130,6 +133,18 @@ def save(self, *args, **kwargs):
         self.set_location()
         super().save(*args, **kwargs)
 
+    @property
+    def file_path_full(self):
+        if self.file_path:
+            return str(settings.IMAGES_DIR / self.file_path)
+        return None
+
+    @property
+    def image_thumb_path_full(self):
+        if self.image_thumb_path:
+            return str(settings.IMAGES_DIR / self.image_thumb_path)
+        return None
+
     @property
     def is_type_single_shop(self):
         return self.type in proof_constants.TYPE_SINGLE_SHOP_LIST

open_prices/proofs/utils.py

@@ -3,6 +3,7 @@
 from mimetypes import guess_extension
 
 from django.conf import settings
+from PIL import Image, ImageOps
 
 
 def get_file_extension_and_mimetype(file) -> tuple[str, str]:
@@ -27,6 +28,52 @@ def get_file_extension_and_mimetype(file) -> tuple[str, str]:
     return extension, mimetype
 
 
+def generate_full_path(current_dir, file_stem, extension):
+    """
+    Generate the full path of the file.
+    Example: /path/to/img/0001/dWQ5Hjm1H6.png
+    """
+    return current_dir / f"{file_stem}{extension}"
+
+
+def generate_relative_path(current_dir_id_str, file_stem, extension):
+    """
+    Generate the relative path of the file.
+    Example: 0001/dWQ5Hjm1H6.png
+    """
+    return f"{current_dir_id_str}/{file_stem}{extension}"
+
+
+def generate_thumbnail(
+    current_dir,
+    current_dir_id_str,
+    file_stem,
+    extension,
+    mimetype,
+    thumbnail_size=settings.THUMBNAIL_SIZE,
+):
+    """Generate a thumbnail for the image at the given path."""
+    image_thumb_path = None
+    if mimetype.startswith("image"):
+        file_full_path = generate_full_path(current_dir, file_stem, extension)
+        with Image.open(file_full_path) as img:
+            img_thumb = img.copy()
+            # set any rotation info
+            img_thumb = ImageOps.exif_transpose(img)
+            # transform into a thumbnail
+            img_thumb.thumbnail(thumbnail_size, Image.Resampling.LANCZOS)
+            image_thumb_full_path = generate_full_path(
+                current_dir, f"{file_stem}.{settings.THUMBNAIL_SIZE[0]}", extension
+            )
+            img_thumb.save(image_thumb_full_path)  # exif will be stripped
+            image_thumb_path = generate_relative_path(
+                current_dir_id_str,
+                f"{file_stem}.{settings.THUMBNAIL_SIZE[0]}",
+                extension,
+            )
+    return image_thumb_path
+
+
 def store_file(file):
     """
     Create a file in the images directory with a random name and the
@@ -36,15 +83,12 @@ def store_file(file):
     :return: the file path and the mimetype
     """
     # Generate a random name for the file
-    # This name will be used to display the image to the client, so it
-    # shouldn't be discoverable
+    # This name will be used to display the image to the client, so it shouldn't be discoverable  # noqa
     file_stem = "".join(random.choices(string.ascii_letters + string.digits, k=10))
     extension, mimetype = get_file_extension_and_mimetype(file)
     # We store the images in directories containing up to 1000 images
-    # Once we reach 1000 images, we create a new directory by increasing
-    # the directory ID
-    # This is used to prevent the base image directory from containing too many
-    # files
+    # Once we reach 1000 images, we create a new directory by increasing the directory ID  # noqa
+    # This is used to prevent the base image directory from containing too many files  # noqa
     images_dir = settings.IMAGES_DIR
     current_dir_id = max(
         (int(p.name) for p in images_dir.iterdir() if p.is_dir() and p.name.isdigit()),
@@ -57,10 +101,14 @@ def store_file(file):
         current_dir_id += 1
         current_dir = images_dir / str(current_dir_id)
     current_dir.mkdir(exist_ok=True, parents=True)
-    full_file_path = current_dir / f"{file_stem}{extension}"
+    file_full_path = generate_full_path(current_dir, file_stem, extension)
     # write the content of the file to the new file
-    with full_file_path.open("wb") as f:
+    with file_full_path.open("wb") as f:
         f.write(file.file.read())
+    # create a thumbnail
+    image_thumb_path = generate_thumbnail(
+        current_dir, current_dir_id_str, file_stem, extension, mimetype
+    )
     # Build file_path
-    file_path = f"{current_dir_id_str}/{file_stem}{extension}"
-    return (file_path, mimetype)
+    file_path = generate_relative_path(current_dir_id_str, file_stem, extension)
+    return (file_path, mimetype, image_thumb_path)

pyproject.toml

@@ -64,6 +64,7 @@ gunicorn = "^22.0.0"
 django-cors-headers = "^4.4.0"
 sentry-sdk = {extras = ["django"], version = "^2.13.0"}
 django-solo = "^2.3.0"
+pillow = "^10.4.0"
 
 [tool.poetry.group.dev.dependencies]
 black = "~23.12.1"