Refactor DCIM forms

netbox/dcim/forms/common.py

@@ -0,0 +1,49 @@
+from django import forms
+
+from dcim.choices import *
+from dcim.constants import *
+
+__all__ = (
+    'InterfaceCommonForm',
+)
+
+
+class InterfaceCommonForm(forms.Form):
+    mac_address = forms.CharField(
+        empty_value=None,
+        required=False,
+        label='MAC address'
+    )
+    mtu = forms.IntegerField(
+        required=False,
+        min_value=INTERFACE_MTU_MIN,
+        max_value=INTERFACE_MTU_MAX,
+        label='MTU'
+    )
+
+    def clean(self):
+        super().clean()
+
+        parent_field = 'device' if 'device' in self.cleaned_data else 'virtual_machine'
+        tagged_vlans = self.cleaned_data.get('tagged_vlans')
+
+        # Untagged interfaces cannot be assigned tagged VLANs
+        if self.cleaned_data['mode'] == InterfaceModeChoices.MODE_ACCESS and tagged_vlans:
+            raise forms.ValidationError({
+                'mode': "An access interface cannot have tagged VLANs assigned."
+            })
+
+        # Remove all tagged VLAN assignments from "tagged all" interfaces
+        elif self.cleaned_data['mode'] == InterfaceModeChoices.MODE_TAGGED_ALL:
+            self.cleaned_data['tagged_vlans'] = []
+
+        # Validate tagged VLANs; must be a global VLAN or in the same site
+        elif self.cleaned_data['mode'] == InterfaceModeChoices.MODE_TAGGED and tagged_vlans:
+            valid_sites = [None, self.cleaned_data[parent_field].site]
+            invalid_vlans = [str(v) for v in tagged_vlans if v.site not in valid_sites]
+
+            if invalid_vlans:
+                raise forms.ValidationError({
+                    'tagged_vlans': f"The tagged VLANs ({', '.join(invalid_vlans)}) must belong to the same site as "
+                                    f"the interface's parent device/VM, or they must be global"
+                })