# Stackdriver Google Cloud Monitoring Output Plugin

This plugin writes to the [Google Cloud Monitoring API][stackdriver] (formerly
Stackdriver) and requires [authentication][] with Google Cloud using either a
service account or user credentials

This plugin accesses APIs which are [chargeable][pricing]; you might incur
costs.

Requires `project` to specify where Stackdriver metrics will be delivered to.

Metrics are grouped by the `namespace` variable and metric key - eg: `custom.googleapis.com/telegraf/system/load5`

[Resource type](https://cloud.google.com/monitoring/api/resources) is configured by the `resource_type` variable (default `global`).

Additional resource labels can be configured by `resource_labels`. By default the required `project_id` label is always set to the `project` variable.

## Configuration

```toml
[[outputs.stackdriver]]
  ## GCP Project
  project = "erudite-bloom-151019"

  ## The namespace for the metric descriptor
  namespace = "telegraf"

  ## Custom resource type
  # resource_type = "generic_node"

  ## Additional resource labels
  # [outputs.stackdriver.resource_labels]
  #   node_id = "$HOSTNAME"
  #   namespace = "myapp"
  #   location = "eu-north0"
```

## Restrictions

Stackdriver does not support string values in custom metrics, any string
fields will not be written.

The Stackdriver API does not allow writing points which are out of order,
older than 24 hours, or more with resolution greater than than one per point
minute.  Since Telegraf writes the newest points first and moves backwards
through the metric buffer, it may not be possible to write historical data
after an interruption.

Points collected with greater than 1 minute precision may need to be
aggregated before then can be written.  Consider using the [basicstats][]
aggregator to do this.

Histogram / distribution and delta metrics are not yet supported. These will
be dropped silently unless debugging is on.

Note that the plugin keeps an in-memory cache of the start times and last
observed values of all COUNTER metrics in order to comply with the
requirements of the stackdriver API.  This cache is not GCed: if you remove
a large number of counters from the input side, you may wish to restart
telegraf to clear it.

[basicstats]: /plugins/aggregators/basicstats/README.md
[stackdriver]: https://cloud.google.com/monitoring/api/v3/
[authentication]: https://cloud.google.com/docs/authentication/getting-started
[pricing]: https://cloud.google.com/stackdriver/pricing#google-clouds-operations-suite-pricing