Grafana
-------

In addition to providing archiver status by way of EPICS PVs, archstats
optionally can write to an elasticsearch database for long-term statistics.
This type of document database is natively supported by Kibana and Grafana.

An example Grafana dashboard that looks like the following is provided in this
repository:

.. image:: https://raw.githubusercontent.com/pcdshub/archstats/assets/images/grafana_1.png
   :target: https://github.com/pcdshub/archstats/blob/master/grafana/example.json

.. image:: https://raw.githubusercontent.com/pcdshub/archstats/assets/images/grafana_2.png
   :target: https://github.com/pcdshub/archstats/blob/master/grafana/example.json

It will need to be tailored for your site, as your elasticsearch index names
will depend on your archiver appliance setup.

Elasticsearch Index
^^^^^^^^^^^^^^^^^^^

By default, the index name will be in the following format::

    archiver-appliance-stats

You should consider using this form and rolling over the database every so
often with a cron job.

You may also configure it for monthly indices by changing the appropriate
environment variables, such as::

    ARCHSTATS_INDEX_FORMAT="archiver-metrics-{appliance}"
    ARCHSTATS_INDEX_SUFFIX="-%Y.%m"

Which would be specified as follows in Grafana::

    [archiver-metrics-APPLIANCE_NAME]-YYYY.MM

Replacing ``APPLIANCE_NAME_HERE`` with your appliance name.  The YYYY.MM
portion at the end indicates that the index will be updated on a monthly basis.
Elasticsearch handles these multiple indices natively.

With the above, the datasource configuration should look like the following in
Grafana:

.. image:: https://raw.githubusercontent.com/pcdshub/archstats/assets/images/datasource.png

Ensure the data source has a minimum interval of 1 minute configured.  This is
the pre-determined update rate archstats uses to not overwhelm the archiver,
and as such there is no benefit to attempting to display any finer granularity
in Grafana panels.