Skip SLO-reconciling probe test when SLO is off

The probe test in question tries to make a manifest referencing
unavailable objects and expects that to fail with a 400. If the SLO
middleware is enabled, then it checks the segments, can't find some,
and returns the 400. If it's disabled, the PUT succeeds and makes an
object whose contents are some JSON blob. In the latter case, the
probe test would fail because it expected a real SLO manifest but
didn't find one.

Now we skip the remainder of the test when we detect that SLO is not
enabled.

Change-Id: I3e7e8e98107608e675efc24156e703bc167458bb

test/probe/test_container_merge_policy_index.py

@@ -20,6 +20,7 @@ import unittest
 
 from nose import SkipTest
 
+from six.moves.urllib.parse import urlparse
 from swift.common.manager import Manager
 from swift.common.internal_client import InternalClient
 from swift.common import utils, direct_client
@@ -237,6 +238,14 @@ class TestContainerMergePolicyIndex(ReplProbeTest):
                         orig_policy_index, node))
 
     def test_reconcile_manifest(self):
+        info_url = "%s://%s/info" % (urlparse(self.url).scheme,
+                                     urlparse(self.url).netloc)
+        proxy_conn = client.http_connection(info_url)
+        cluster_info = client.get_capabilities(proxy_conn)
+        if 'slo' not in cluster_info:
+            raise SkipTest("SLO not enabled in proxy; "
+                           "can't test manifest reconciliation")
+
         # this test is not only testing a split brain scenario on
         # multiple policies with mis-placed objects - it even writes out
         # a static large object directly to the storage nodes while the
@@ -278,18 +287,18 @@ class TestContainerMergePolicyIndex(ReplProbeTest):
             write_part(i)
 
         # write manifest
-        try:
+        with self.assertRaises(ClientException) as catcher:
             client.put_object(self.url, self.token, self.container_name,
                               self.object_name,
                               contents=utils.json.dumps(manifest_data),
                               query_string='multipart-manifest=put')
-        except ClientException as err:
-            # so as it works out, you can't really upload a multi-part
-            # manifest for objects that are currently misplaced - you have to
-            # wait until they're all available - which is about the same as
-            # some other failure that causes data to be unavailable to the
-            # proxy at the time of upload
-            self.assertEqual(err.http_status, 400)
+
+        # so as it works out, you can't really upload a multi-part
+        # manifest for objects that are currently misplaced - you have to
+        # wait until they're all available - which is about the same as
+        # some other failure that causes data to be unavailable to the
+        # proxy at the time of upload
+        self.assertEqual(catcher.exception.http_status, 400)
 
         # but what the heck, we'll sneak one in just to see what happens...
         direct_manifest_name = self.object_name + '-direct-test'