Add download functionality for case DICOMs and metadata as ZIP

atlas/views.py

@@ -48,6 +48,10 @@ from django.urls.exceptions import NoReverseMatch
 from django.http import Http404, JsonResponse
 from django.http import HttpResponseRedirect, HttpResponse
 from django.contrib.contenttypes.models import ContentType
+import zipfile
+import os
+from django.core.files.base import ContentFile
+from django.core.exceptions import PermissionDenied
 
 from generic.models import CidUser, CidUserExam, CimarCase, Site
 from atlas.helpers import get_cases_available_to_user
@@ -3373,6 +3377,71 @@ class SeriesImagesZipView(SeriesImagesZipViewBase, SuperuserRequiredMixin):
     series_object = Series
 
 
+@login_required
+def case_download(request, pk):
+    """Allow a case author (or superuser) to download all linked series DICOMs
+    and a metadata export as a zip file.
+    """
+    case = get_object_or_404(Case, pk=pk)
+
+    # Only allow superusers or case authors
+    if not (request.user.is_superuser or case.author.filter(id=request.user.id).exists()):
+        raise PermissionDenied()
+
+    temp_file = ContentFile(b"", name=f"case_{case.pk}.zip")
+    with zipfile.ZipFile(temp_file, mode="w", compression=zipfile.ZIP_DEFLATED) as zip_file:
+        metadata = {
+            "case": {
+                "id": case.pk,
+                "title": case.title,
+                "authors": [str(a) for a in case.author.all()],
+            },
+            "series": [],
+        }
+
+        # Iterate ordered series if available, otherwise fall back to related series
+        try:
+            ordered_series = case.get_ordered_series()
+        except Exception:
+            ordered_series = list(case.series.all())
+
+        for series in ordered_series:
+            series_entry = {"pk": series.pk, "description": str(series)}
+            # Prefer series-provided dicom JSON if available
+            try:
+                series_entry["dicom_json"] = series.get_series_dicom_json()
+            except Exception:
+                series_entry["dicom_json"] = None
+
+            images = series.images.filter(removed=False).order_by("position")
+            series_entry["images"] = []
+            for img in images:
+                try:
+                    file_obj = img.image.file
+                    fname = os.path.split(file_obj.name)[-1]
+                    arcname = f"series_{series.pk}/{fname}"
+                    zip_file.writestr(arcname, file_obj.read())
+                    series_entry["images"].append({"filename": fname, "position": img.position})
+                except Exception:
+                    # skip missing files
+                    continue
+
+            metadata["series"].append(series_entry)
+
+        # Write metadata.json
+        zip_file.writestr("metadata.json", json.dumps(metadata, default=str, indent=2))
+
+    file_size = temp_file.tell()
+    temp_file.seek(0)
+
+    response = HttpResponse(temp_file, content_type="application/zip")
+    response["Content-Disposition"] = (
+        "attachment; filename=%s" % f"case_{case.pk}.zip"
+    )
+    response["Content-Length"] = file_size
+    return response
+
+
 # At the moment only the series owner / author can delete findings but anyone can create
 def create_series_findings(request):
     # posts = Post.objects.all()