Relax cleanliness condition to allow the empty tree

When, at cluster init, checking for left overs of a previous
cluster, only look for spurious files. This will the directory
structure to be set up ahead of time.
Signed-off-by: Klaus Aehlig <aehlig@google.com>
Reviewed-by: Petr Pudlak <pudlak@google.com>

lib/bootstrap.py

@@ -576,20 +576,16 @@ def InitCluster(cluster_name, mac_prefix, # pylint: disable=R0913, R0914
                                errors.ECODE_STATE)
 
   data_dir = vcluster.AddNodePrefix(pathutils.DATA_DIR)
-  if os.path.isdir(data_dir):
-    for entry in os.listdir(data_dir):
-      if not os.path.isdir(os.path.join(data_dir, entry)):
-        raise errors.OpPrereqError(
-          "%s contains non-directory enries like %s. Remove left-overs of an"
-          " old cluster before initialising a new one" % (data_dir, entry),
-          errors.ECODE_STATE)
-
   queue_dir = vcluster.AddNodePrefix(pathutils.QUEUE_DIR)
-  if os.path.isdir(queue_dir) and os.listdir(queue_dir):
-    raise errors.OpPrereqError(
-      "%s not empty. Remove left-overs of an old cluster before initialising"
-      " a new one" % queue_dir,
-      errors.ECODE_STATE)
+  archive_dir = vcluster.AddNodePrefix(pathutils.JOB_QUEUE_ARCHIVE_DIR)
+  for ddir in [queue_dir, data_dir, archive_dir]:
+    if os.path.isdir(ddir):
+      for entry in os.listdir(ddir):
+        if not os.path.isdir(os.path.join(ddir, entry)):
+          raise errors.OpPrereqError(
+            "%s contains non-directory enries like %s. Remove left-overs of an"
+            " old cluster before initialising a new one" % (ddir, entry),
+            errors.ECODE_STATE)
 
   if not enabled_hypervisors:
     raise errors.OpPrereqError("Enabled hypervisors list must contain at"