Updated models and added post-save hook

migrations/0002_auto_20180301_1654.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.0.2 on 2018-03-01 16:54
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='asset',
+            name='asset_id',
+            field=models.IntegerField(blank=True),
+        ),
+    ]

migrations/0003_auto_20180301_1700.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.0.2 on 2018-03-01 17:00
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0002_auto_20180301_1654'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='asset',
+            name='purchase_price',
+            field=models.IntegerField(blank=True, null=True),
+        ),
+    ]

migrations/0004_auto_20180301_1711.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.0.2 on 2018-03-01 17:11
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0003_auto_20180301_1700'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='asset',
+            name='collection',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, to='assets.Collection'),
+        ),
+    ]

migrations/0005_auto_20180301_1725.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.0.2 on 2018-03-01 17:25
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0004_auto_20180301_1711'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='asset',
+            name='asset_id',
+            field=models.IntegerField(blank=True, null=True),
+        ),
+    ]

models.py

@@ -1,4 +1,8 @@
 from django.db import models
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+from django.urls import reverse
+
 
 class AssetCategory(models.Model):
     class Meta:
@@ -6,6 +10,9 @@ class AssetCategory(models.Model):
         verbose_name_plural = 'Asset Categories'
     name = models.CharField(max_length=80)
 
+    def __str__(self):
+        return self.name
+
 
 class AssetStatus(models.Model):
     class Meta:
@@ -13,17 +20,26 @@ class AssetStatus(models.Model):
         verbose_name_plural = 'Asset Statuses'
     name = models.CharField(max_length=80)
 
+    def __str__(self):
+        return self.name
+
 
 class Supplier(models.Model):
     name = models.CharField(max_length=80)
 
+    def __str__(self):
+        return self.name
+
 
 class Collection(models.Model):
     name = models.CharField(max_length=80)
 
+    def __str__(self):
+        return self.name
+
 
 class Asset(models.Model):
-    asset_id = models.IntegerField()
+    asset_id = models.IntegerField(blank=True, null=True)
     description = models.CharField(max_length=120)
     category = models.ForeignKey(to=AssetCategory, on_delete=models.CASCADE)
     status = models.ForeignKey(to=AssetStatus, on_delete=models.CASCADE)
@@ -31,9 +47,27 @@ class Asset(models.Model):
     purchased_from = models.ForeignKey(to=Supplier, on_delete=models.CASCADE, blank=True, null=True)
     date_acquired = models.DateField()
     date_sold = models.DateField(blank=True, null=True)
-    purchase_price = models.IntegerField()
+    purchase_price = models.IntegerField(blank=True, null=True)
     salvage_value = models.IntegerField(blank=True, null=True)
     comments = models.TextField(blank=True, null=True)
     next_sched_maint = models.DateField(blank=True, null=True)
 
-    collection = models.ForeignKey(to=Collection, on_delete=models.CASCADE)
+    collection = models.ForeignKey(to=Collection, on_delete=models.CASCADE, blank=True, null=True)
+
+    def get_absolute_url(self):
+        return reverse('asset_detail', kwargs={'pk': self.pk})
+
+    def __str__(self):
+        return str(self.asset_id) + ' - ' + self.description
+
+
+# Automatically updates Asset.asset_id to Asset.pk if none is given by the user
+@receiver(post_save, sender=Asset)
+def update_asset_id(sender, instance, **kwargs):
+    post_save.disconnect(update_asset_id, sender=sender)
+
+    if not instance.asset_id:
+        instance.asset_id = instance.pk
+    instance.save()
+
+    post_save.connect(update_asset_id, sender=sender)