Feature/location types (#5588)

* Added model changes for StockLocationTypes

* Implement icon for CUI

* Added location type to location table with filters

* Fix ruleset

* Added tests

* Bump api version to v136

* trigger: ci

* Bump api version variable too

InvenTree/stock/models.py

@@ -41,6 +41,66 @@ from plugin.events import trigger_event
 from users.models import Owner
 
 
+class StockLocationType(MetadataMixin, models.Model):
+    """A type of stock location like Warehouse, room, shelf, drawer.
+
+    Attributes:
+        name: brief name
+        description: longer form description
+        icon: icon class
+    """
+
+    class Meta:
+        """Metaclass defines extra model properties."""
+
+        verbose_name = _("Stock Location type")
+        verbose_name_plural = _("Stock Location types")
+
+    @staticmethod
+    def get_api_url():
+        """Return API url."""
+        return reverse('api-location-type-list')
+
+    def __str__(self):
+        """String representation of a StockLocationType."""
+        return self.name
+
+    name = models.CharField(
+        blank=False,
+        max_length=100,
+        verbose_name=_("Name"),
+        help_text=_("Name"),
+    )
+
+    description = models.CharField(
+        blank=True,
+        max_length=250,
+        verbose_name=_("Description"),
+        help_text=_("Description (optional)")
+    )
+
+    icon = models.CharField(
+        blank=True,
+        max_length=100,
+        verbose_name=_("Icon"),
+        help_text=_("Default icon for all locations that have no icon set (optional)")
+    )
+
+
+class StockLocationManager(TreeManager):
+    """Custom database manager for the StockLocation class.
+
+    StockLocation querysets will automatically select related fields for performance.
+    """
+
+    def get_queryset(self):
+        """Prefetch queryset to optimize db hits.
+
+        - Joins the StockLocationType by default for speedier icon access
+        """
+        return super().get_queryset().select_related("location_type")
+
+
 class StockLocation(InvenTreeBarcodeMixin, MetadataMixin, InvenTreeTree):
     """Organization tree for StockItem objects.
 
@@ -48,6 +108,8 @@ class StockLocation(InvenTreeBarcodeMixin, MetadataMixin, InvenTreeTree):
     Stock locations can be hierarchical as required
     """
 
+    objects = StockLocationManager()
+
     class Meta:
         """Metaclass defines extra model properties"""
 
@@ -107,11 +169,12 @@ class StockLocation(InvenTreeBarcodeMixin, MetadataMixin, InvenTreeTree):
         """Return API url."""
         return reverse('api-location-list')
 
-    icon = models.CharField(
+    custom_icon = models.CharField(
         blank=True,
         max_length=100,
         verbose_name=_("Icon"),
-        help_text=_("Icon (optional)")
+        help_text=_("Icon (optional)"),
+        db_column="icon",
     )
 
     owner = models.ForeignKey(Owner, on_delete=models.SET_NULL, blank=True, null=True,
@@ -133,6 +196,38 @@ class StockLocation(InvenTreeBarcodeMixin, MetadataMixin, InvenTreeTree):
         help_text=_('This is an external stock location')
     )
 
+    location_type = models.ForeignKey(
+        StockLocationType,
+        on_delete=models.SET_NULL,
+        verbose_name=_("Location type"),
+        related_name="stock_locations",
+        null=True, blank=True,
+        help_text=_("Stock location type of this location"),
+    )
+
+    @property
+    def icon(self):
+        """Get the current icon used for this location.
+
+        The icon field on this model takes precedences over the possibly assigned stock location type
+        """
+        if self.custom_icon:
+            return self.custom_icon
+
+        if self.location_type:
+            return self.location_type.icon
+
+        return ""
+
+    @icon.setter
+    def icon(self, value):
+        """Setter to keep model API compatibility. But be careful:
+
+        If the field gets loaded as default value by any form which is later saved,
+        the location no longer inherits its icon from the location type.
+        """
+        self.custom_icon = value
+
     def get_location_owner(self):
         """Get the closest "owner" for this location.