Datadog has a nice dashboard system, but I was having trouble creating a dashboard that combined multiple datasources and grafana was the easiest way to bring it all together.
Fork, make your change, and submit a Pull Request. Make sure you add tests where approprate, and don't break exisisting tests.
It's easy - select aggregation and metric. If you want to filter result, select one or more tags.
DataDog datasource supports advanced functions. Select it from dropdown and arrange by clicking function name.
Annotations allows to get events from DataDog and display it on graph. You can filter events by sources, tags and priority.
There are two options for getting values of tempate variable - metrics and tags. For fetching list of available metrics leave Query field blank or specify *. For tags type tag. Filter results by using Regex field. Multi-value variables are supported for using in tags (selected values will be converted into comma separated list of tags).
There's new special type of template variable in Grafana called Ad-hoc filters. This variable will apply to all DataDog queries on dashboard (all with specified datasource). This alollows to use it like a quick filter. Ad-hoc variable for DataDog fetches all key-value pairs from tags, for example, region:east, region:west, and use it as queries tags. To create this variable, select Ad-hoc filters type and choose your DataDog datasource. You can set any name to this variable.