Handle non-JSON responses on image check

arkindex/images/models.py

@@ -6,6 +6,7 @@ from django.db.models.functions import Concat, Substr
 from django.utils.functional import cached_property
 from django.utils.text import slugify
 from enumfields import EnumField
+from json import JSONDecodeError
 from arkindex.images.managers import ImageServerManager
 from arkindex.project.aws import S3FileMixin, S3FileStatus
 from arkindex.project.fields import StripSlashURLField, LStripTextField, MD5HashField
@@ -221,7 +222,11 @@ class Image(S3FileMixin, IndexableModel):
             # Load info
             resp = requests.get(info_url, timeout=15, allow_redirects=True)
             resp.raise_for_status()
-            self.check_from_payload(resp.json())
+            try:
+                payload = resp.json()
+            except JSONDecodeError:
+                raise ValueError('Server returned an invalid JSON document')
+            self.check_from_payload(payload)
         except Exception as e:
             logger.warning('Image check failed: {}'.format(str(e)))
             self.status = S3FileStatus.Error

arkindex/images/tests/test_perform_check.py

@@ -23,10 +23,32 @@ class TestImagePerformCheck(FixtureTestCase):
             self.img.perform_check(raise_exc=True, save=False)
         self.assertEqual(self.img.status, S3FileStatus.Error)
 
+    @responses.activate
+    def test_empty(self):
+        """
+        Test Image.perform_check fails when the server returns nothing
+        """
+        responses.add(responses.GET, 'http://server/img1/info.json', status=200)
+        self.img.status = S3FileStatus.Unchecked
+        with self.assertRaisesRegex(ValueError, 'Server returned an invalid JSON document'):
+            self.img.perform_check(raise_exc=True, save=False)
+        self.assertEqual(self.img.status, S3FileStatus.Error)
+
+    @responses.activate
+    def test_json(self):
+        """
+        Test Image.perform_check fails when the server returns invalid JSON
+        """
+        responses.add(responses.GET, 'http://server/img1/info.json', body='<blink>oh no</blink>')
+        self.img.status = S3FileStatus.Unchecked
+        with self.assertRaisesRegex(ValueError, 'Server returned an invalid JSON document'):
+            self.img.perform_check(raise_exc=True, save=False)
+        self.assertEqual(self.img.status, S3FileStatus.Error)
+
     @responses.activate
     def test_required_items(self):
         """
-        Test Image.perform_check fails on a HTTP error code
+        Test Image.perform_check fails when required items are missing from the JSON payload
         """
         base_payload = {
             '@id': 'http://server/img1',
@@ -38,7 +60,7 @@ class TestImagePerformCheck(FixtureTestCase):
             payload = base_payload.copy()
             del payload[key]
             responses.add(responses.GET, 'http://server/img1/info.json', json=payload)
-            with self.assertRaises(AssertionError, msg='Missing required properties'):
+            with self.assertRaisesRegex(AssertionError, 'Missing required properties'):
                 self.img.perform_check(raise_exc=True, save=False)
             self.assertEqual(self.img.status, S3FileStatus.Error)