added check for 404 response if not found

test/test_classifier_routes.py

@@ -95,3 +95,11 @@ def test_peer_info(client_with_mocked_data, peer_address, peer_type):
         "peer should be only vpn-rr or ix-public, not both"
 
     assert peer_type in response_data
+
+
+def test_peer_not_found(client_with_mocked_data):
+
+    rv = client_with_mocked_data.get(
+        '/classifier/peer-info/1.2.3.4.5',
+        headers = DEFAULT_REQUEST_HEADERS)
+    assert rv.status_code == 404