diff --git a/workers/securityworker.py b/workers/securityworker.py
index 487b2f537..fb59754ac 100644
--- a/workers/securityworker.py
+++ b/workers/securityworker.py
@@ -26,6 +26,49 @@ unscanned_images_gauge = prometheus.create_gauge('unscanned_images',
 max_unscanned_images_gauge = prometheus.create_gauge('max_unscanned_image_id',
                                                      'Max ID of the unscanned images.')
 
+def index_images(min_id, target_version, analyzer):
+  def batch_query():
+    return get_images_eligible_for_scan(target_version)
+
+  # Get the ID of the last image we can analyze. Will be None if there are no images in the
+  # database.
+  max_id = get_max_id_for_sec_scan()
+  if max_id is None:
+    return None
+
+  if min_id is None or min_id > max_id:
+    logger.info('Could not find any available images for scanning.')
+    return None
+
+  max_unscanned_images_gauge.Set(max_id)
+
+  # 4^log10(total) gives us a scalable batch size into the billions.
+  batch_size = int(4 ** log10(max(10, max_id - min_id)))
+
+  with UseThenDisconnect(app.config):
+    to_scan_generator = yield_random_entries(
+      batch_query,
+      get_image_pk_field(),
+      batch_size,
+      max_id,
+      min_id,
+    )
+    for candidate, abt, num_remaining in to_scan_generator:
+      try:
+        analyzer.analyze_recursively(candidate)
+      except PreemptedException:
+        logger.info('Another worker pre-empted us for layer: %s', candidate.id)
+        abt.set()
+      except APIRequestFailure:
+        logger.exception('Security scanner service unavailable')
+        return
+
+      unscanned_images_gauge.Set(num_remaining)
+
+  # If we reach this point, we analyzed every images up to max_id, next time the worker runs,
+  # we want to start from the next image.
+  return max_id + 1
+
 class SecurityWorker(Worker):
   def __init__(self):
     super(SecurityWorker, self).__init__()
@@ -42,48 +85,9 @@ class SecurityWorker(Worker):
     self.add_operation(self._index_images, interval)
 
   def _index_images(self):
-    def batch_query():
-      return get_images_eligible_for_scan(self._target_version)
-
-    # Get the ID of the last image we can analyze. Will be None if there are no images in the
-    # database.
-    max_id = get_max_id_for_sec_scan()
-    if max_id is None:
-      return
-
-    if self.min_id is None or self.min_id > max_id:
-      logger.info('Could not find any available images for scanning.')
-      return
-
-    max_unscanned_images_gauge.Set(max_id)
-
-    # 4^log10(total) gives us a scalable batch size into the billions.
-    batch_size = int(4 ** log10(max(10, max_id - self.min_id)))
-
-    with UseThenDisconnect(app.config):
-      to_scan_generator = yield_random_entries(
-        batch_query,
-        get_image_pk_field(),
-        batch_size,
-        max_id,
-        self.min_id,
-      )
-      for candidate, abt, num_remaining in to_scan_generator:
-        try:
-          self._analyzer.analyze_recursively(candidate)
-        except PreemptedException:
-          logger.info('Another worker pre-empted us for layer: %s', candidate.id)
-          abt.set()
-        except APIRequestFailure:
-          logger.exception('Security scanner service unavailable')
-          return
-
-        unscanned_images_gauge.Set(num_remaining)
-
-    # If we reach this point, we analyzed every images up to max_id, next time the worker runs,
-    # we want to start from the next image.
-    self.min_id = max_id + 1
-
+    new_min_id = index_images(self.min_id, self._target_version, self._analyzer)
+    if new_min_id is not None:
+      self.min_id = new_min_id
 
   @property
   def min_id(self):
diff --git a/workers/test/test_securityworker.py b/workers/test/test_securityworker.py
new file mode 100644
index 000000000..de3927450
--- /dev/null
+++ b/workers/test/test_securityworker.py
@@ -0,0 +1,9 @@
+from mock import patch, Mock
+
+from test.fixtures import *
+from workers.securityworker import index_images
+
+def test_securityworker_realdb(initialized_db):
+  mock_analyzer = Mock()
+  assert index_images(0, 1, mock_analyzer) is not None
+  mock_analyzer.analyze_recursively.assert_called()