Add basic validation of item prerequisites

Currently throws the worlds most unhelpful error message...

training/forms.py

@@ -16,6 +16,13 @@ class QualificationForm(forms.ModelForm):
             self.fields['trainee'].initial = Profile.objects.get(pk=pk)
         self.fields['date'].widget.format = '%Y-%m-%d'
 
+    def clean(self):
+        cleaned_data = super().clean()
+        item = cleaned_data.get('item')
+        trainee = cleaned_data.get('trainee')
+        if not item.user_has_requirements(trainee):
+            self.add_error('item', 'Missing prerequisites')
+
     def clean_date(self):
         date = self.cleaned_data['date']
         if date > date.today():

training/management/commands/import_old_db.py

@@ -104,19 +104,19 @@ class Command(BaseCommand):
                 obj, created = models.TrainingItem.objects.update_or_create(
                     pk=int(child.find('ID').text),
                     reference_number=number,
-                    name=name,
+                    description=name,
                     category=category,
                     active=active
                 )
             except IntegrityError:
-                print("Training Item {}.{} {} has a duplicate reference number".format(category.reference_number, number, name))
+                print(f"Training Item {category.reference_number}.{number} {name} has a duplicate reference number")
 
             if created:
                 tally[1] += 1
             else:
                 tally[0] += 1
 
-        print('Training Items - Updated: {}, Created: {}'.format(tally[0], tally[1]))
+        print(f'Training Items - Updated: {tally[0]}, Created: {tally[1]}')
 
     def import_TrainingItemQualification(self):
         tally = [0, 0, 0]
@@ -129,9 +129,9 @@ class Command(BaseCommand):
                       ("Competency_Assessed", models.TrainingItemQualification.PASSED_OUT), ]
 
             for (depth, depth_index) in depths:
-                if child.find('{}_Date'.format(depth)) is not None:
+                if child.find(f'{depth}_Date') is not None:
-                    if child.find('{}_Assessor_ID'.format(depth)) is None:
+                    if child.find(f'{depth}_Assessor_ID') is None:
-                        print("Training Record #{} had no supervisor. Assigning System User.".format(child.find('ID').text))
+                        print(f"Training Record #{child.find('ID').text} had no supervisor. Assigning System User.")
                         supervisor = Profile.objects.get(first_name="God")
                         continue
                     supervisor = Profile.objects.get(pk=self.id_map[child.find('{}_Assessor_ID'.format(depth)).text])

training/migrations/0005_auto_20220223_1535.py

@@ -0,0 +1,22 @@
+# Generated by Django 3.2.12 on 2022-02-23 15:35
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('training', '0004_rename_name_trainingitem_description'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='trainingcategory',
+            options={'ordering': ['reference_number'], 'verbose_name_plural': 'Training Categories'},
+        ),
+        migrations.AddField(
+            model_name='trainingitem',
+            name='prerequisites',
+            field=models.ManyToManyField(blank=True, to='training.TrainingItem'),
+        ),
+    ]

training/models.py

@@ -75,6 +75,7 @@ class TrainingCategory(models.Model):
 
     class Meta:
         verbose_name_plural = 'Training Categories'
+        ordering = ['reference_number']
 
 
 class TrainingItemManager(QueryablePropertiesManager):
@@ -92,6 +93,7 @@ class TrainingItem(models.Model):
     category = models.ForeignKey('TrainingCategory', related_name='items', on_delete=models.CASCADE)
     description = models.CharField(max_length=50)
     active = models.BooleanField(default=True)
+    prerequisites = models.ManyToManyField('self', symmetrical=False, blank=True)
 
     objects = TrainingItemManager()
 
@@ -124,6 +126,13 @@ class TrainingItem(models.Model):
     def get_absolute_url(self):
         return reverse('item_list')
 
+    def has_prereqs(self):
+        return self.prerequisites.all().exists()
+
+    def user_has_requirements(self, user):
+        # Always true if there are no prerequisites, otherwise get a set of prerequsite IDs and check if they are a subset of the set of qualification IDs
+        return not self.has_prereqs() or set(self.prerequisites.values_list('pk', flat=True)).issubset(set(user.qualifications_obtained.values_list('item', flat=True)))
+
     @staticmethod
     def user_has_qualification(item, user, depth):
         return user.qualifications_obtained.only('item', 'depth').filter(item=item, depth__gte=depth).exists()

training/templates/item_list.html

@@ -13,11 +13,18 @@
       <div class="card-body">
         <div class="list-group list-group-flush">
             {% for item in category.items.all %}
-            {% if item.active %}
+                <li class="list-group-item {% if not item.active%}text-warning{%endif%}">{{ item }}
-            <li class="list-group-item">{{ item }}</li>
+                {% if item.prerequisites.exists %}
-            {% elif request.user.is_superuser %}
+                    <div class="ml-3 font-italic">
-            <li class="list-group-item text-warning">{{ item }}</li>
+                    <p class="text-info mb-0">Prerequisites:</p>
+                    <ul>
+                    {% for p in item.prerequisites.all %}
+                    <li>{{p}}</li>
+                    {% endfor %}
+                    </ul>
+                    </div>
                 {% endif %}
+                </li>
             {% endfor %}
         </div>
       </div>