Add "updated_at" field to Orders model

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - [#11383](https://github.com/inventree/InvenTree/pull/11383) adds "exists_for_model_id", "exists_for_related_model", and "exists_for_related_model_id" filters to the ParameterTemplate API endpoint. These filters allow users to check for the existence of parameters associated with specific models or related models, improving the flexibility and usability of the API.
 - [#10887](https://github.com/inventree/InvenTree/pull/10887) adds the ability to auto-allocate tracked items against specific build outputs. Currently, this will only allocate items where the serial number of the tracked item matches the serial number of the build output, but in future this may be extended to allow for more flexible allocation rules.
 - [#11372](https://github.com/inventree/InvenTree/pull/11372) adds backup metadata setter and restore metadata validator functions to ensure common footguns are harder to trigger when using the backup and restore functionality.
+- [#11374](https://github.com/inventree/InvenTree/pull/11374) adds `updated_at` field on purchase, sales and return orders.
 
 ### Changed
 

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,11 +1,16 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 459
+INVENTREE_API_VERSION = 460
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 INVENTREE_API_TEXT = """
 
+v460 -> 2026-02-25 : https://github.com/inventree/InvenTree/pull/11374
+    - Adds "updated_at" field to PurchaseOrder, SalesOrder and ReturnOrder API endpoints
+    - Adds "updated_before" and "updated_after" date filters to all three order list endpoints
+    - Adds "updated_at" ordering option to all three order list endpoints
+
 v459 -> 2026-02-23 : https://github.com/inventree/InvenTree/pull/11411
     - Changed PurchaseOrderLine "auto_pricing" default value from true to false
 

src/backend/InvenTree/order/api.py

@@ -228,6 +228,14 @@ def filter_has_target_date(self, queryset, name, value):
         label=_('Target Date After'), field_name='target_date', lookup_expr='gt'
     )
 
+    updated_before = InvenTreeDateFilter(
+        label=_('Updated Before'), field_name='updated_at', lookup_expr='lt'
+    )
+
+    updated_after = InvenTreeDateFilter(
+        label=_('Updated After'), field_name='updated_at', lookup_expr='gt'
+    )
+
     min_date = InvenTreeDateFilter(label=_('Min Date'), method='filter_min_date')
 
     def filter_min_date(self, queryset, name, value):
@@ -420,6 +428,7 @@ class PurchaseOrderList(
         'responsible',
         'total_price',
         'project_code',
+        'updated_at',
     ]
 
     ordering = '-reference'
@@ -882,6 +891,7 @@ class SalesOrderList(
         'shipment_date',
         'total_price',
         'project_code',
+        'updated_at',
     ]
 
     search_fields = [
@@ -1549,6 +1559,7 @@ class ReturnOrderList(
         'target_date',
         'complete_date',
         'project_code',
+        'updated_at',
     ]
 
     search_fields = [

src/backend/InvenTree/order/migrations/0115_purchaseorder_updated_at_returnorder_updated_at_and_more.py

@@ -0,0 +1,43 @@
+# Generated by Django 5.2.11 on 2026-02-19 22:31
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("order", "0114_purchaseorderextraline_project_code_and_more"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="purchaseorder",
+            name="updated_at",
+            field=models.DateTimeField(
+                blank=True,
+                null=True,
+                help_text="Timestamp of last update",
+                verbose_name="Updated At",
+            ),
+        ),
+        migrations.AddField(
+            model_name="returnorder",
+            name="updated_at",
+            field=models.DateTimeField(
+                blank=True,
+                null=True,
+                help_text="Timestamp of last update",
+                verbose_name="Updated At",
+            ),
+        ),
+        migrations.AddField(
+            model_name="salesorder",
+            name="updated_at",
+            field=models.DateTimeField(
+                blank=True,
+                null=True,
+                help_text="Timestamp of last update",
+                verbose_name="Updated At",
+            ),
+        ),
+    ]

src/backend/InvenTree/order/models.py

@@ -9,7 +9,7 @@
 from django.db import models, transaction
 from django.db.models import F, Q, QuerySet, Sum
 from django.db.models.functions import Coalesce
-from django.db.models.signals import post_save
+from django.db.models.signals import post_delete, post_save
 from django.dispatch.dispatcher import receiver
 from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
@@ -331,6 +331,8 @@ def save(self, *args, **kwargs):
         if not self.creation_date:
             self.creation_date = InvenTree.helpers.current_date()
 
+        self.updated_at = InvenTree.helpers.current_time()
+
         super().save(*args, **kwargs)
 
     def check_locked(self, db: bool = False) -> bool:
@@ -498,6 +500,13 @@ def is_overdue(self):
         help_text=_('Date order was issued'),
     )
 
+    updated_at = models.DateTimeField(
+        null=True,
+        blank=True,
+        verbose_name=_('Updated At'),
+        help_text=_('Timestamp of last update'),
+    )
+
     responsible = models.ForeignKey(
         UserModels.Owner,
         on_delete=models.SET_NULL,
@@ -3072,3 +3081,43 @@ def get_api_url():
         verbose_name=_('Order'),
         help_text=_('Return Order'),
     )
+
+
+def _touch_order_updated_at(instance):
+    """Bump updated_at on the parent order without triggering a full save."""
+    if not InvenTree.ready.canAppAccessDatabase(allow_test=True):
+        return
+    instance.order.__class__.objects.filter(pk=instance.order_id).update(
+        updated_at=InvenTree.helpers.current_time()
+    )
+
+
+@receiver(post_save, sender=PurchaseOrderLineItem, dispatch_uid='po_lineitem_post_save')
+@receiver(
+    post_delete, sender=PurchaseOrderLineItem, dispatch_uid='po_lineitem_post_delete'
+)
+@receiver(
+    post_save, sender=PurchaseOrderExtraLine, dispatch_uid='po_extraline_post_save'
+)
+@receiver(
+    post_delete, sender=PurchaseOrderExtraLine, dispatch_uid='po_extraline_post_delete'
+)
+@receiver(post_save, sender=SalesOrderLineItem, dispatch_uid='so_lineitem_post_save')
+@receiver(
+    post_delete, sender=SalesOrderLineItem, dispatch_uid='so_lineitem_post_delete'
+)
+@receiver(post_save, sender=SalesOrderExtraLine, dispatch_uid='so_extraline_post_save')
+@receiver(
+    post_delete, sender=SalesOrderExtraLine, dispatch_uid='so_extraline_post_delete'
+)
+@receiver(post_save, sender=ReturnOrderLineItem, dispatch_uid='ro_lineitem_post_save')
+@receiver(
+    post_delete, sender=ReturnOrderLineItem, dispatch_uid='ro_lineitem_post_delete'
+)
+@receiver(post_save, sender=ReturnOrderExtraLine, dispatch_uid='ro_extraline_post_save')
+@receiver(
+    post_delete, sender=ReturnOrderExtraLine, dispatch_uid='ro_extraline_post_delete'
+)
+def update_order_on_lineitem_change(sender, instance, **kwargs):
+    """Update parent order updated_at when any line item is saved or deleted."""
+    _touch_order_updated_at(instance)

src/backend/InvenTree/order/serializers.py

@@ -373,8 +373,14 @@ class Meta:
             'total_price',
             'order_currency',
             'destination',
+            'updated_at',
         ])
-        read_only_fields = ['issue_date', 'complete_date', 'creation_date']
+        read_only_fields = [
+            'issue_date',
+            'complete_date',
+            'creation_date',
+            'updated_at',
+        ]
         extra_kwargs = {
             'supplier': {'required': True},
             'order_currency': {'required': False},
@@ -1026,8 +1032,9 @@ class Meta:
             'shipments_count',
             'completed_shipments_count',
             'allocated_lines',
+            'updated_at',
         ])
-        read_only_fields = ['status', 'creation_date', 'shipment_date']
+        read_only_fields = ['status', 'creation_date', 'shipment_date', 'updated_at']
         extra_kwargs = {'order_currency': {'required': False}}
 
     def skip_create_fields(self):
@@ -1918,8 +1925,9 @@ class Meta:
             'customer_reference',
             'order_currency',
             'total_price',
+            'updated_at',
         ])
-        read_only_fields = ['creation_date']
+        read_only_fields = ['creation_date', 'updated_at']
 
     def skip_create_fields(self):
         """Skip these fields when instantiating a new object."""