Merge "Adding validation check for Spark plugin"

sahara/plugins/spark/plugin.py

@@ -75,6 +75,15 @@ class SparkProvider(p.ProvisioningPluginBase):
             raise ex.InvalidComponentCountException("datanode", _("1 or more"),
                                                     nn_count)
 
+        rep_factor = c_helper.get_config_value('HDFS', "dfs.replication",
+                                               cluster)
+        if dn_count < rep_factor:
+            raise ex.InvalidComponentCountException(
+                'datanode', _('%s or more') % rep_factor, dn_count,
+                _('Number of %(dn)s instances should not be less '
+                  'than %(replication)s')
+                % {'dn': 'datanode', 'replication': 'dfs.replication'})
+
         # validate Spark Master Node and Spark Slaves
         sm_count = sum([ng.count for ng
                         in utils.get_node_groups(cluster, "master")])

sahara/tests/integration/tests/gating/test_spark_gating.py

@@ -76,8 +76,7 @@ class SparkGatingTest(swift.SwiftTest, scaling.ScalingTest,
             'name': 'test-cluster-template-spark',
             'plugin_config': self.plugin_config,
             'description': 'test cluster template for Spark plugin',
-            'cluster_configs': {
-            },
+            'cluster_configs': {'HDFS': {'dfs.replication': 1}},
             'node_groups': [
                 {
                     'name': 'master-node',