Why

So the datasource is automatically available to Grafana users and can be used by our default dashboards (e.g. App Metrics)

How

• Add the datasource to this file https://github.com/aerogearcatalog/metrics-apb/blob/ca15f9b2758254a3294fe6304b641a9c171eb487/roles/provision-metrics-apb/templates/grafana-data-sources.yml.j2
• It should be possible to reference the POSTGRES_ env vars in that file e.g. user & passowrd vars
• The name of the datasource should be 'Postgres'