Correctly handles the unique constraint on feature_slot

5 files changed, 88 insertions, 69 deletions

diff --git a/pyblackbird_cc/resources/forms.py b/pyblackbird_cc/resources/forms.py
index ca38640..d0fb001 100644
--- a/pyblackbird_cc/resources/forms.py
+++ b/pyblackbird_cc/resources/forms.py
@@ -56,7 +56,8 @@ class ResourceCreateForm(forms.Form):
     card_description = forms.CharField(
         max_length=1000,
         widget=forms.Textarea,
-        help_text="If you enter text here, it will be used in the 'card' description box on the home page. Max 1000 characters.",
+        help_text=("If you enter text here, it will be used in the 'card' description "
+                   "box on the home page. Max 1000 characters."),
     )
     resource_type = forms.ModelChoiceField(queryset=ResourceType.objects.all())
     age_range = forms.ChoiceField(
@@ -111,7 +112,8 @@ class ResourceCreateForm(forms.Form):
         min_value=1,
         max_value=3,
         required=False,
-        help_text="Please enter either 1, 2 or 3 here. This will dictate where on the page this resource will feature on the main list page.",
+        help_text=("Please enter either 1, 2 or 3 here. This will dictate where on the page "
+                   "this resource will feature on the main list page."),
     )
 
     def clean_thumbnail_files(self):
diff --git a/pyblackbird_cc/resources/migrations/0009_alter_resource_feature_slot.py b/pyblackbird_cc/resources/migrations/0009_alter_resource_feature_slot.py
new file mode 100644
index 0000000..ca082d4
--- /dev/null
+++ b/pyblackbird_cc/resources/migrations/0009_alter_resource_feature_slot.py
@@ -0,0 +1,18 @@
+# Generated by Django 5.0.4 on 2024-05-26 18:17
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('resources', '0008_alter_resource_card_description'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='resource',
+            name='feature_slot',
+            field=models.IntegerField(blank=True, choices=[(1, 1), (2, 2), (3, 3)], default=0, null=True, unique=True),
+        ),
+    ]
diff --git a/pyblackbird_cc/resources/models.py b/pyblackbird_cc/resources/models.py
index 0d1bbe3..33fd678 100644
--- a/pyblackbird_cc/resources/models.py
+++ b/pyblackbird_cc/resources/models.py
@@ -60,7 +60,8 @@ class Resource(models.Model):
         max_length=1000,
         blank=True,
         default="",
-        help_text="If you enter text here, it will be used in the 'card' description box on the home page. Max 1000 characters.",
+        help_text=("If you enter text here, it will be used in the 'card' "
+                   "description box on the home page. Max 1000 characters."),
     )
     age_range = models.CharField(
         max_length=20,
@@ -80,7 +81,7 @@ class Resource(models.Model):
         ],
     )
     feature_slot = models.IntegerField(
-        choices=((0, 0), (1, 1), (2, 2), (3, 3)), unique=True, null=True, blank=True, default=0,
+        choices=((1, 1), (2, 2), (3, 3)), unique=True, null=True, blank=True, default=0,
     )
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
@@ -94,8 +95,7 @@ class Resource(models.Model):
     def get_pdf_snapshot_file_names(self):
         rs = self.pdf_resources.all()
         sh = [sh for sh in rs.values_list("pdf_page_snapshots__file_name", flat=True)]
-        out = [s for s in sh if s]
-        return out
+        return [s for s in sh if s]
 
 
 class ResourceType(models.Model):
@@ -151,17 +151,3 @@ class PDFPageSnapshot(models.Model):
 
     def __str__(self):
         return self.name
-
-
-# class FeatureResource(models.Model):
-#     resource = models.ForeignKey(
-#         "Resource",
-#         on_delete=models.CASCADE,
-#         null=False,
-#         related_name="feature_resources",
-#     )
-#     slot = models.IntegerField(null=False, choices=[(1, 1), (2, 2), (3, 3)])
-#     description = models.CharField(max_length=255, null=False)
-#
-#     def __str__(self):
-#         return f"{self.resource.name} as a feature in slot {self.slot}"
diff --git a/pyblackbird_cc/resources/views.py b/pyblackbird_cc/resources/views.py
index ea8953f..667fb0d 100644
--- a/pyblackbird_cc/resources/views.py
+++ b/pyblackbird_cc/resources/views.py
@@ -8,7 +8,9 @@ import boto3
 from botocore.exceptions import ClientError
 from botocore.utils import Path
 from django.conf import settings
+from django.contrib import messages
 from django.contrib.auth.decorators import login_required
+from django.db import IntegrityError
 from django.db import transaction
 from django.shortcuts import get_object_or_404
 from django.shortcuts import redirect
@@ -216,6 +218,7 @@ def create_metadata(
             yield metadata, snapshot_images
 
 
+#FIXME: Can't find a caller for this - delete it
 @transaction.atomic
 def create_resource_objects(resource, metadata_generator, thumbnail_files):
     for metadata, snapshot_images in metadata_generator:
@@ -255,48 +258,53 @@ def create_resource(request):
             feature_slot = form.cleaned_data["feature_slot"]
 
             try:
-                resource = Resource.objects.create(
-                    name=name,
-                    description=description,
-                    card_description=card_description,
-                    resource_type=resource_type,
-                    age_range=age_range,
-                    curriculum=curriculum,
-                    main_resource_category=main_resource_category,
-                    additional_resource_category=additional_resource_category,
-                    feature_slot=feature_slot,
-                )
-
-                metadata_generator = create_metadata(pdf_files)
-                snapshotted_pages = []
-
-                for metadata, snapshot_images in metadata_generator:
-                    pdf_resource = PDFResource.objects.create(
-                        resource=resource,
-                        file_name=os.path.basename(metadata.file_name),
-                        file_size=metadata.file_size,
+                with transaction.atomic():
+                    resource = Resource.objects.create(
+                        name=name,
+                        description=description,
+                        card_description=card_description,
+                        resource_type=resource_type,
+                        age_range=age_range,
+                        curriculum=curriculum,
+                        main_resource_category=main_resource_category,
+                        additional_resource_category=additional_resource_category,
+                        feature_slot=feature_slot,
                     )
 
-                    for snapshot_image in snapshot_images:
-                        PDFPageSnapshot.objects.create(
-                            name="test",
-                            file_name=os.path.basename(snapshot_image),
-                            pdf_file=pdf_resource,
+                    metadata_generator = create_metadata(pdf_files)
+                    snapshotted_pages = []
+
+                    for metadata, snapshot_images in metadata_generator:
+                        pdf_resource = PDFResource.objects.create(
+                            resource=resource,
+                            file_name=os.path.basename(metadata.file_name),
+                            file_size=metadata.file_size,
                         )
 
-                    snapshotted_pages.append(snapshot_images)
+                        for snapshot_image in snapshot_images:
+                            PDFPageSnapshot.objects.create(
+                                name="test",
+                                file_name=os.path.basename(snapshot_image),
+                                pdf_file=pdf_resource,
+                            )
+
+                        snapshotted_pages.append(snapshot_images)
 
-                resource.thumbnail_filenames = [f.name for f in thumbnail_files]
-                resource.save()
+                    resource.thumbnail_filenames = [f.name for f in thumbnail_files]
+                    resource.save()
 
-                # Reset the file pointers for pdf_files
-                for pdf_file in pdf_files:
-                    pdf_file.seek(0)
+                    # Reset the file pointers for pdf_files
+                    for pdf_file in pdf_files:
+                        pdf_file.seek(0)
 
-                if not upload_to_s3(pdf_files, thumbnail_files, snapshotted_pages):
-                    raise Exception("Error uploading files to S3")
+                    if not upload_to_s3(pdf_files, thumbnail_files, snapshotted_pages):
+                        raise Exception("Error uploading files to S3")
 
-                return redirect("resources:resource_detail", resource_id=resource.id)
+                    return redirect("resources:resource_detail", resource_id=resource.id)
+            except IntegrityError:
+                slot = form.cleaned_data["feature_slot"]
+                messages.add_message(request, messages.ERROR, f"Feature slot {slot} is already "
+                                     "in use. Quit this form and remove from existing resource.")
             except Exception:
                 logger.exception("Error creating resource")
                 form.add_error(None, "An error occurred while creating the resource.")
diff --git a/pyblackbird_cc/templates/resources/create_featured_resource.html b/pyblackbird_cc/templates/resources/create_featured_resource.html
index e98b2ba..19022fc 100644
--- a/pyblackbird_cc/templates/resources/create_featured_resource.html
+++ b/pyblackbird_cc/templates/resources/create_featured_resource.html
@@ -1,21 +1,26 @@
 {% extends "base.html" %}
-{% load static %}
 
-{% block title %}Add featured resource{% endblock title %}
+{% load static %}
 
+{% block title %}
+  Add featured resource
+{% endblock title %}
 {% block content %}
-
-{% if request.user.is_authenticated and request.user.is_staff %}
-  <div class="row d-flex justify-content-center">
-    <div class="col bg-light mt-lg-4 p-4 border border-success border-opacity-25 rounded">
-      <h2>Configure featured resources</h2>
-      <p>You can select three resources to be "featured" on the main page</p>
+  {% if messages %}
+    <ul class="messages">
+      {% for message in messages %}
+        <li {% if message.tags %}class="{{ message.tags }}"{% endif %}>{{ message }}</li>
+      {% endfor %}
+    </ul>
+  {% endif %}
+  {% if request.user.is_authenticated and request.user.is_staff %}
+    <div class="row d-flex justify-content-center">
+      <div class="col bg-light mt-lg-4 p-4 border border-success border-opacity-25 rounded">
+        <h2>Configure featured resources</h2>
+        <p>You can select three resources to be "featured" on the main page</p>
+      </div>
     </div>
-  </div>
-{% else %}
-  <p>You must be a super-user to access this page.</p>
-{% endif %}
-
-
+  {% else %}
+    <p>You must be a super-user to access this page.</p>
+  {% endif %}
 {% endblock content %}
-