Load default settings on InvenTree launch

InvenTree/common/apps.py

@@ -1,5 +1,43 @@
 from django.apps import AppConfig
+from django.db.utils import OperationalError
+
+import yaml
 
 
 class CommonConfig(AppConfig):
     name = 'common'
+
+    def ready(self):
+        """ Will be called when the Common app is first loaded """
+        self.populate_default_settings()
+
+    def populate_default_settings(self):
+        """ Populate the default values for InvenTree key:value pairs.
+        If a setting does not exist, it will be created.
+        """
+
+        from .models import InvenTreeSetting
+
+        with open('./common/kvp.yaml') as kvp:
+            values = yaml.safe_load(kvp)
+
+        for value in values:
+            key = value['key']
+            default = value['default']
+            description = value['description']
+
+            try:
+                # If a particular setting does not exist in the database, create it now
+                if not InvenTreeSetting.objects.filter(key=key).exists():
+                    setting = InvenTreeSetting(
+                        key=key,
+                        value=default,
+                        description=description
+                    )
+
+                    setting.save()
+
+                    print("Creating new key: '{k}' = '{v}'".format(k=key, v=default))
+            except OperationalError:
+                # Migrations have not yet been applied - table does not exist
+                break

InvenTree/common/kvp.yaml

@@ -0,0 +1,13 @@
+# This file contains the default values for the key:value settings available in InvenTree
+# This file should not be edited locally.
+
+# Note: The description strings provided here will be translatable,
+#       so ensure that any translations are provided as appropriate.
+
+- key: 'part_ipn_regex'
+  default: ''
+  description: 'Format string for internal part number'
+  
+- key: part_deep_copy
+  default: True
+  description: 'Parts are deep-copied by default'

InvenTree/common/migrations/0006_auto_20200203_0951.py

@@ -0,0 +1,17 @@
+# Generated by Django 2.2.9 on 2020-02-03 09:51
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('common', '0005_auto_20190915_1256'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='inventreesetting',
+            options={'verbose_name': 'InvenTree Setting', 'verbose_name_plural': 'InvenTree Settings'},
+        ),
+    ]

InvenTree/common/models.py

@@ -21,6 +21,10 @@ class InvenTreeSetting(models.Model):
     even if that key does not exist.
     """
 
+    class Meta:
+        verbose_name = "InvenTree Setting"
+        verbose_name_plural = "InvenTree Settings"
+
     @classmethod
     def get_setting(cls, key, backup_value=None):
         """

InvenTree/part/templatetags/inventree_extras.py

@@ -6,6 +6,8 @@ from django import template
 from InvenTree import version
 from InvenTree.helpers import decimal2string
 
+from common.models import InvenTreeSetting
+
 register = template.Library()
 
 
@@ -69,3 +71,8 @@ def inventree_github_url(*args, **kwargs):
 def inventree_docs_url(*args, **kwargs):
     """ Return URL for InvenTree documenation site """
     return "https://inventree.github.io"
+
+
+@register.simple_tag()
+def inventree_setting(key, *args, **kwargs):
+    return InvenTreeSetting.get_setting(key)