Enhancement: allow negative workflow trigger offset

src/documents/migrations/1066_alter_workflowtrigger_schedule_offset_days.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.1.7 on 2025-04-15 19:18
+
+from django.db import migrations
+from django.db import models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("documents", "1065_workflowaction_assign_custom_fields_values"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="workflowtrigger",
+            name="schedule_offset_days",
+            field=models.IntegerField(
+                default=0,
+                help_text="The number of days to offset the schedule trigger by.",
+                verbose_name="schedule offset days",
+            ),
+        ),
+    ]

src/documents/models.py

@@ -1019,7 +1019,7 @@ class WorkflowTrigger(models.Model):
         verbose_name=_("has this correspondent"),
     )
 
-    schedule_offset_days = models.PositiveIntegerField(
+    schedule_offset_days = models.IntegerField(
         _("schedule offset days"),
         default=0,
         help_text=_(

src/documents/tasks.py

@@ -1,8 +1,8 @@
+import datetime
 import hashlib
 import logging
 import shutil
 import uuid
-from datetime import timedelta
 from pathlib import Path
 from tempfile import TemporaryDirectory
 
@@ -356,7 +356,7 @@ def empty_trash(doc_ids=None):
         if doc_ids is not None
         else Document.deleted_objects.filter(
             deleted_at__lt=timezone.localtime(timezone.now())
-            - timedelta(
+            - datetime.timedelta(
                 days=settings.EMPTY_TRASH_DELAY,
             ),
         )
@@ -396,6 +396,7 @@ def check_scheduled_workflows():
     )
     if scheduled_workflows.count() > 0:
         logger.debug(f"Checking {len(scheduled_workflows)} scheduled workflows")
+        now = timezone.now()
         for workflow in scheduled_workflows:
             schedule_triggers = workflow.triggers.filter(
                 type=WorkflowTrigger.WorkflowTriggerType.SCHEDULED,
@@ -403,31 +404,60 @@ def check_scheduled_workflows():
             trigger: WorkflowTrigger
             for trigger in schedule_triggers:
                 documents = Document.objects.none()
-                offset_td = timedelta(days=trigger.schedule_offset_days)
+                offset_td = datetime.timedelta(days=-trigger.schedule_offset_days)
+                threshold = now - offset_td
                 logger.debug(
-                    f"Checking trigger {trigger} with offset {offset_td} against field: {trigger.schedule_date_field}",
+                    f"Trigger {trigger.id}: checking if (date + {offset_td}) <= now ({now})",
                 )
+
                 match trigger.schedule_date_field:
                     case WorkflowTrigger.ScheduleDateField.ADDED:
-                        documents = Document.objects.filter(
-                            added__lt=timezone.now() - offset_td,
-                        )
+                        documents = Document.objects.filter(added__lte=threshold)
+
                     case WorkflowTrigger.ScheduleDateField.CREATED:
-                        documents = Document.objects.filter(
-                            created__lt=timezone.now() - offset_td,
-                        )
+                        documents = Document.objects.filter(created__lte=threshold)
+
                     case WorkflowTrigger.ScheduleDateField.MODIFIED:
-                        documents = Document.objects.filter(
-                            modified__lt=timezone.now() - offset_td,
-                        )
+                        documents = Document.objects.filter(modified__lte=threshold)
+
                     case WorkflowTrigger.ScheduleDateField.CUSTOM_FIELD:
-                        cf_instances = CustomFieldInstance.objects.filter(
-                            field=trigger.schedule_date_custom_field,
-                            value_date__lt=timezone.now() - offset_td,
-                        )
-                        documents = Document.objects.filter(
-                            id__in=cf_instances.values_list("document", flat=True),
+                        # cap earliest date to avoid massive scans
+                        earliest_date = now - datetime.timedelta(days=365)
+                        if offset_td.days < -365:
+                            logger.warning(
+                                f"Trigger {trigger.id} has large negative offset ({offset_td.days}), "
+                                f"limiting earliest scan date to {earliest_date}",
+                            )
+
+                        cf_filter_kwargs = {
+                            "field": trigger.schedule_date_custom_field,
+                            "value_date__isnull": False,
+                            "value_date__lte": threshold,
+                            "value_date__gte": earliest_date,
+                        }
+
+                        recent_cf_instances = CustomFieldInstance.objects.filter(
+                            **cf_filter_kwargs,
                         )
+
+                        matched_ids = [
+                            cfi.document_id
+                            for cfi in recent_cf_instances
+                            if cfi.value_date
+                            and (
+                                timezone.make_aware(
+                                    datetime.datetime.combine(
+                                        cfi.value_date,
+                                        datetime.time.min,
+                                    ),
+                                )
+                                + offset_td
+                                <= now
+                            )
+                        ]
+
+                        documents = Document.objects.filter(id__in=matched_ids)
+
                 if documents.count() > 0:
                     logger.debug(
                         f"Found {documents.count()} documents for trigger {trigger}",
@@ -439,18 +469,18 @@ def check_scheduled_workflows():
                             workflow=workflow,
                         ).order_by("-run_at")
                         if not trigger.schedule_is_recurring and workflow_runs.exists():
-                            # schedule is non-recurring and the workflow has already been run
                             logger.debug(
                                 f"Skipping document {document} for non-recurring workflow {workflow} as it has already been run",
                             )
                             continue
-                        elif (
+
+                        if (
                             trigger.schedule_is_recurring
                             and workflow_runs.exists()
                             and (
                                 workflow_runs.last().run_at
-                                > timezone.now()
-                                - timedelta(
+                                > now
+                                - datetime.timedelta(
                                     days=trigger.schedule_recurring_interval_days,
                                 )
                             )

src/documents/tests/test_workflows.py

@@ -1600,6 +1600,56 @@ class TestWorkflows(
             doc.refresh_from_db()
             self.assertIsNone(doc.owner)
 
+    def test_workflow_scheduled_trigger_negative_offset(self):
+        """
+        GIVEN:
+            - Existing workflow with SCHEDULED trigger and negative offset of -7 days
+        WHEN:
+            - Scheduled workflows are checked for document with custom field date 8 days in the past
+        THEN:
+            - Workflow runs and document owner is updated
+        """
+        trigger = WorkflowTrigger.objects.create(
+            type=WorkflowTrigger.WorkflowTriggerType.SCHEDULED,
+            schedule_offset_days=-7,
+            schedule_date_field=WorkflowTrigger.ScheduleDateField.CUSTOM_FIELD,
+            schedule_date_custom_field=self.cf1,
+        )
+        action = WorkflowAction.objects.create(
+            assign_title="Doc assign owner",
+            assign_owner=self.user2,
+        )
+        w = Workflow.objects.create(
+            name="Workflow 1",
+            order=0,
+        )
+        w.triggers.add(trigger)
+        w.actions.add(action)
+        w.save()
+
+        doc = Document.objects.create(
+            title="sample test",
+            correspondent=self.c,
+            original_filename="sample.pdf",
+        )
+        cfi = CustomFieldInstance.objects.create(
+            document=doc,
+            field=self.cf1,
+            value_date=timezone.now() - timedelta(days=5),
+        )
+
+        tasks.check_scheduled_workflows()
+
+        doc.refresh_from_db()
+        self.assertIsNone(doc.owner)  # has not triggered yet
+
+        cfi.value_date = timezone.now() - timedelta(days=8)
+        cfi.save()
+
+        tasks.check_scheduled_workflows()
+        doc.refresh_from_db()
+        self.assertEqual(doc.owner, self.user2)
+
     def test_workflow_enabled_disabled(self):
         trigger = WorkflowTrigger.objects.create(
             type=WorkflowTrigger.WorkflowTriggerType.DOCUMENT_ADDED,