Give the people what they want (#6021)

* Add 'existing_image' field to part API serializer

* Ensure that the specified directory exists

* Fix serializer

- Use CharField instead of FilePathField
- Custom validation
- Save part with existing image

* Add unit test for new feature

* Bump API version

.gitignore

@@ -42,6 +42,7 @@ dummy_image.*
 _tmp.csv
 InvenTree/label.pdf
 InvenTree/label.png
+InvenTree/part_image_123abc.png
 label.pdf
 label.png
 InvenTree/my_special*

InvenTree/InvenTree/api_version.py

@@ -2,11 +2,14 @@
 
 
 # InvenTree API version
-INVENTREE_API_VERSION = 156
+INVENTREE_API_VERSION = 157
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 INVENTREE_API_TEXT = """
 
+v157 -> 2023-12-02 : https://github.com/inventree/InvenTree/pull/6021
+    - Add write-only "existing_image" field to Part API serializer
+
 v156 -> 2023-11-26 : https://github.com/inventree/InvenTree/pull/5982
     - Add POST endpoint for report and label creation
 

InvenTree/InvenTree/serializers.py

@@ -864,7 +864,7 @@ def skip_create_fields(self):
         required=False,
         allow_blank=False,
         write_only=True,
-        label=_("URL"),
+        label=_("Remote Image"),
         help_text=_("URL of remote image file"),
     )
 

InvenTree/part/helpers.py

@@ -1,6 +1,9 @@
 """Various helper functions for the part app"""
 
 import logging
+import os
+
+from django.conf import settings
 
 from jinja2 import Environment
 
@@ -66,3 +69,28 @@ def render_part_full_name(part) -> str:
     # Fallback to the default format
     elements = [el for el in [part.IPN, part.name, part.revision] if el]
     return ' | '.join(elements)
+
+
+# Subdirectory for storing part images
+PART_IMAGE_DIR = "part_images"
+
+
+def get_part_image_directory() -> str:
+    """Return the directory where part images are stored.
+
+    Returns:
+        str: Directory where part images are stored
+
+    TODO: Future work may be needed here to support other storage backends, such as S3
+    """
+
+    part_image_directory = os.path.abspath(os.path.join(
+        settings.MEDIA_ROOT,
+        PART_IMAGE_DIR,
+    ))
+
+    # Create the directory if it does not exist
+    if not os.path.exists(part_image_directory):
+        os.makedirs(part_image_directory)
+
+    return part_image_directory

InvenTree/part/models.py

@@ -293,7 +293,8 @@ def rename_part_image(instance, filename):
     Returns:
         Cleaned filename in format part_<n>_img
     """
-    base = 'part_images'
+
+    base = part_helpers.PART_IMAGE_DIR
     fname = os.path.basename(filename)
 
     return os.path.join(base, fname)

InvenTree/part/serializers.py

@@ -3,6 +3,7 @@
 import imghdr
 import io
 import logging
+import os
 from decimal import Decimal
 
 from django.core.exceptions import ValidationError
@@ -27,6 +28,7 @@
 import InvenTree.serializers
 import InvenTree.status
 import part.filters
+import part.helpers as part_helpers
 import part.stocktake
 import part.tasks
 import stock.models
@@ -511,6 +513,8 @@ class Meta:
             'description',
             'full_name',
             'image',
+            'remote_image',
+            'existing_image',
             'IPN',
             'is_template',
             'keywords',
@@ -522,7 +526,6 @@ class Meta:
             'parameters',
             'pk',
             'purchaseable',
-            'remote_image',
             'revision',
             'salable',
             'starred',
@@ -608,7 +611,8 @@ def skip_create_fields(self):
             'duplicate',
             'initial_stock',
             'initial_supplier',
-            'copy_category_parameters'
+            'copy_category_parameters',
+            'existing_image',
         ]
 
         return fields
@@ -761,6 +765,33 @@ def get_starred(self, part):
         help_text=_('Copy parameter templates from selected part category'),
     )
 
+    # Allow selection of an existing part image file
+    existing_image = serializers.CharField(
+        label=_('Existing Image'),
+        help_text=_('Filename of an existing part image'),
+        write_only=True,
+        required=False,
+        allow_blank=False,
+    )
+
+    def validate_existing_image(self, img):
+        """Validate the selected image file"""
+        if not img:
+            return img
+
+        img = img.split(os.path.sep)[-1]
+
+        # Ensure that the file actually exists
+        img_path = os.path.join(
+            part_helpers.get_part_image_directory(),
+            img
+        )
+
+        if not os.path.exists(img_path) or not os.path.isfile(img_path):
+            raise ValidationError(_('Image file does not exist'))
+
+        return img
+
     @transaction.atomic
     def create(self, validated_data):
         """Custom method for creating a new Part instance using this serializer"""
@@ -869,6 +900,18 @@ def save(self):
         super().save()
 
         part = self.instance
+        data = self.validated_data
+
+        existing_image = data.pop('existing_image', None)
+
+        if existing_image:
+            img_path = os.path.join(
+                part_helpers.PART_IMAGE_DIR,
+                existing_image
+            )
+
+            part.image = img_path
+            part.save()
 
         # Check if an image was downloaded from a remote URL
         remote_img = getattr(self, 'remote_image_file', None)

InvenTree/part/test_api.py

@@ -1,5 +1,6 @@
 """Unit tests for the various part API endpoints"""
 
+import os
 from datetime import datetime
 from decimal import Decimal
 from enum import IntEnum
@@ -1464,6 +1465,16 @@ def test_category_parameters(self):
 class PartDetailTests(PartAPITestBase):
     """Test that we can create / edit / delete Part objects via the API."""
 
+    @classmethod
+    def setUpTestData(cls):
+        """Custom setup routine for this class"""
+        super().setUpTestData()
+
+        # Create a custom APIClient for file uploads
+        # Ref: https://stackoverflow.com/questions/40453947/how-to-generate-a-file-upload-test-request-with-django-rest-frameworks-apireq
+        cls.upload_client = APIClient()
+        cls.upload_client.force_authenticate(user=cls.user)
+
     def test_part_operations(self):
         """Test that Part instances can be adjusted via the API"""
         n = Part.objects.count()
@@ -1643,17 +1654,12 @@ def test_image_upload(self):
         with self.assertRaises(ValueError):
             print(p.image.file)
 
-        # Create a custom APIClient for file uploads
-        # Ref: https://stackoverflow.com/questions/40453947/how-to-generate-a-file-upload-test-request-with-django-rest-frameworks-apireq
-        upload_client = APIClient()
-        upload_client.force_authenticate(user=self.user)
-
         # Try to upload a non-image file
         with open('dummy_image.txt', 'w') as dummy_image:
             dummy_image.write('hello world')
 
         with open('dummy_image.txt', 'rb') as dummy_image:
-            response = upload_client.patch(
+            response = self.upload_client.patch(
                 url,
                 {
                     'image': dummy_image,
@@ -1672,7 +1678,7 @@ def test_image_upload(self):
             img.save(fn)
 
             with open(fn, 'rb') as dummy_image:
-                response = upload_client.patch(
+                response = self.upload_client.patch(
                     url,
                     {
                         'image': dummy_image,
@@ -1686,6 +1692,55 @@ def test_image_upload(self):
             p = Part.objects.get(pk=pk)
             self.assertIsNotNone(p.image)
 
+    def test_existing_image(self):
+        """Test that we can allocate an existing uploaded image to a new Part"""
+
+        # First, upload an image for an existing part
+        p = Part.objects.first()
+
+        fn = 'part_image_123abc.png'
+
+        img = PIL.Image.new('RGB', (128, 128), color='blue')
+        img.save(fn)
+
+        with open(fn, 'rb') as img_file:
+            response = self.upload_client.patch(
+                reverse('api-part-detail', kwargs={'pk': p.pk}),
+                {
+                    'image': img_file,
+                },
+            )
+
+            self.assertEqual(response.status_code, 200)
+            image_name = response.data['image']
+            self.assertTrue(image_name.startswith('/media/part_images/part_image'))
+
+        # Attempt to create, but with an invalid image name
+        response = self.post(
+            reverse('api-part-list'),
+            {
+                'name': 'New part',
+                'description': 'New Part description',
+                'category': 1,
+                'existing_image': 'does_not_exist.png',
+            },
+            expected_code=400
+        )
+
+        # Now, create a new part and assign the same image
+        response = self.post(
+            reverse('api-part-list'),
+            {
+                'name': 'New part',
+                'description': 'New part description',
+                'category': 1,
+                'existing_image': image_name.split(os.path.sep)[-1]
+            },
+            expected_code=201,
+        )
+
+        self.assertEqual(response.data['image'], image_name)
+
     def test_details(self):
         """Test that the required details are available."""
         p = Part.objects.get(pk=1)

InvenTree/part/views.py

@@ -17,6 +17,7 @@
 from company.models import SupplierPart
 from InvenTree.helpers import str2bool, str2int
 from InvenTree.views import AjaxUpdateView, AjaxView, InvenTreeRoleMixin
+from part.helpers import PART_IMAGE_DIR
 from plugin.views import InvenTreePluginViewMixin
 from stock.models import StockItem, StockLocation
 
@@ -398,12 +399,12 @@ def post(self, request, *args, **kwargs):
         data = {}
 
         if img:
-            img_path = settings.MEDIA_ROOT.joinpath('part_images', img)
+            img_path = settings.MEDIA_ROOT.joinpath(PART_IMAGE_DIR, img)
 
             # Ensure that the image already exists
             if os.path.exists(img_path):
 
-                part.image = os.path.join('part_images', img)
+                part.image = os.path.join(PART_IMAGE_DIR, img)
                 part.save()
 
                 data['success'] = _('Updated part image')