Set embargoedUntil to actual unembargo timestamp upon status transition

dandiapi/api/models/version.py

@@ -11,6 +11,7 @@
 from django.core.validators import RegexValidator
 from django.db import models
 from django.db.models.query_utils import Q
+from django.utils import timezone
 from django_extensions.db.models import TimeStampedModel
 
 from dandiapi.api.asset_paths import get_root_paths
@@ -216,13 +217,26 @@ def _populate_access_metadata(self):
         # Ensure that every item in access is a dict
         access = [x for x in access if isinstance(x, dict)] or default_access
 
+        new_status = (
+            AccessType.EmbargoedAccess.value
+            if self.dandiset.embargoed
+            else AccessType.OpenAccess.value
+        )
+
+        # When transitioning from embargoed to open access, record the actual
+        # unembargo timestamp in embargoedUntil.
+        # See https://github.com/dandi/dandi-schema/pull/143 for the field semantics.
+        if (
+            access[0].get('status') == AccessType.EmbargoedAccess.value
+            and new_status == AccessType.OpenAccess.value
+        ):
+            access[0]['embargoedUntil'] = timezone.now().isoformat()
+
         # Set first access item
         access[0] = {
             **access[0],
             'schemaKey': 'AccessRequirements',
-            'status': AccessType.EmbargoedAccess.value
-            if self.dandiset.embargoed
-            else AccessType.OpenAccess.value,
+            'status': new_status,
         }
 
         return access

dandiapi/api/tests/test_unembargo.py

@@ -1,9 +1,11 @@
 from __future__ import annotations
 
+import datetime
 from typing import TYPE_CHECKING
 
 import dandischema
 from django.core.files.storage import default_storage
+from django.utils import timezone
 import pytest
 
 from dandiapi.api.manifests import all_manifest_filepaths
@@ -255,10 +257,22 @@ def test_unembargo_dandiset(
 
     write_manifest_files(draft_version.id)
 
+    # Seed access metadata to match what would exist in reality: the version was
+    # created while EMBARGOED (with EmbargoedAccess status and a future embargoedUntil),
+    # then kickoff changed the dandiset to UNEMBARGOING without saving the version.
+    original_embargoed_until = '2099-01-01T00:00:00+00:00'
+    draft_version.metadata['access'][0]['status'] = (
+        dandischema.models.AccessType.EmbargoedAccess.value
+    )
+    draft_version.metadata['access'][0]['embargoedUntil'] = original_embargoed_until
+    draft_version.save()
+
     assert all(asset.is_embargoed for asset in draft_version.assets.all())
     assert all(asset.status == Asset.Status.VALID for asset in draft_version.assets.all())
 
+    before_unembargo = timezone.now()
     unembargo_dandiset(dandiset, owners[0])
+    after_unembargo = timezone.now()
 
     for zarr_file in zarr_files:
         zarr_file_s3_path = zarr_archive.s3_path(str(zarr_file.path))
@@ -277,6 +291,12 @@ def test_unembargo_dandiset(
         == dandischema.models.AccessType.OpenAccess.value
     )
 
+    # Verify embargoedUntil was replaced with the actual unembargo timestamp
+    embargoed_until = draft_version.metadata['access'][0]['embargoedUntil']
+    assert embargoed_until != original_embargoed_until
+    embargoed_until_dt = datetime.datetime.fromisoformat(embargoed_until)
+    assert before_unembargo <= embargoed_until_dt <= after_unembargo
+
     # Check that a correct email exists
     assert mailoutbox
     assert 'has been unembargoed' in mailoutbox[0].subject