A metrics graph becomes not to appear when adding/deleting a dimension.

[Sayako Kondo]

1. NOT specify the dimension in configuration file(/etc/monasca/agent/conf.d/kafka_consumer.yaml) and restart monasca-agent.
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init_config:
instances:
 - consumer_groups:
     '1_alarm-state-transitions':
        'alarm-state-transitions': [0, 1]
   kafka_connect_str: localhost:9092
   zk_connect_str: localhost:2181
   per_partition: True
   zk_prefix: /0.8
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2. open Monitoring Dashboard from Alarm tab of Horizon GUI. and the metrics graph appears.

3. edit kafka_consumer.yaml to add the dimension as below and restart monasca-agent.
------------------------------
init_config:
instances:
 - consumer_groups:
     '1_alarm-state-transitions':
        'alarm-state-transitions': [0, 1]
   kafka_connect_str: localhost:9092
   zk_connect_str: localhost:2181
   per_partition: True
   zk_prefix: /0.8
   dimensions:
     dim1: val1
------------------------------

4. The 2 metrics, one doesn't have the dimension(dim1) and the other has dimension(dim1), are displayed in "Matching Metrics" of "Create Alarm Definition", however the graph for each data are NOT displayed on "Graph Metrics" (please see the attachement).

Then occur the below error in /var/log/monasca/api/monasca-api.log.
ERROR [2015-08-18 11:54:37,251] monasca.api.resource.exception.Exceptions: CONFLICT 4ff4f0c9d6955483 - Found multiple metrics matching metric name and dimensions. Please refine your search criteria using a unique metric name or additional dimensions. Alternatively, you may specify 'merge_metrics=true' as a query param to combine all metrics matching search criteria into a single series. search criteria: {metric name: kafka.consumer_lag, dimensions: {topic=metrics, consumer_group=1_metrics, component=kafka, service=monitoring, hostname=mini-mon}}