Use ujson instead of json for parsing messages

ujson is simply faster than json :)

Change-Id: I1f33dda01cc4ee09f0bae1c2d2a33fbda65c1cac

monasca_persister/repositories/cassandra/alarm_state_history_repository.py

@@ -12,7 +12,7 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import json
+import ujson as json
 
 from cassandra import query
 from oslo_log import log

monasca_persister/repositories/cassandra/metrics_repository.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import hashlib
-import json
+import ujson as json
 
 from cassandra import query
 from oslo_log import log

monasca_persister/repositories/influxdb/alarm_state_history_repository.py

@@ -12,7 +12,7 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import json
+import ujson as json
 
 from oslo_log import log
 

monasca_persister/repositories/influxdb/line_utils.py

@@ -28,12 +28,17 @@ def escape_tag(tag):
         u"=", u"\\="
     )
 
+
 def get_unicode(data):
     if PY2:
-        return unicode(data)
+        if isinstance(data, unicode):
+            return data
+        else:
+            return data.decode('utf-8')
     else:
         return str(data)
 
+
 def escape_value(value):
     return u"\"{0}\"".format(
         get_unicode(value).replace(

monasca_persister/repositories/influxdb/metrics_repository.py

@@ -12,7 +12,7 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import json
+import ujson as json
 
 from oslo_log import log
 

monasca_persister/repositories/utils.py

@@ -12,7 +12,7 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import json
+import ujson as json
 
 
 def parse_measurement_message(message):