Cloud Monitoring Exporter Example
=================================

These examples show how to use OpenTelemetry to send metrics data to Cloud Monitoring.


Basic Example
-------------

To use this exporter you first need to:

* `Create a Google Cloud project <https://console.cloud.google.com/projectcreate>`_.
* Set up `Application Default Credentials
  <https://cloud.google.com/docs/authentication/provide-credentials-adc>`_ by `installing
  gcloud <https://cloud.google.com/sdk/install>`_ and running ``gcloud auth
  application-default login``.

* Installation

.. code-block:: sh

    pip install opentelemetry-exporter-gcp-monitoring \
        opentelemetry-api \
        opentelemetry-sdk 

* Run example code

.. literalinclude:: basic_metrics.py
    :language: python
    :lines: 1-

Viewing Output
--------------------------

After running the example:

* Go to the `Cloud Monitoring Metrics Explorer page <https://console.cloud.google.com/monitoring/metrics-explorer>`_.
* In "Select a Metric" enter "workload.googleapis.com/request_counter".
* You can filter by labels and change the graphical output here as well.

Troubleshooting
--------------------------

``One or more points were written more frequently than the maximum sampling period configured for the metric``
##############################################################################################################

Currently, Cloud Monitoring allows one write every 5 seconds for any unique tuple (metric_name, metric_label_value_1, metric_label_value_2, ...). The exporter should rate limit on its own but issues arise if:

* You are restarting the server more than once every 5 seconds.
* You have a multiple exporters (possibly on different threads) writing to the same tuple.

For both cases, you can pass ``add_unique_identifier=True`` to the CloudMonitoringMetricsExporter constructor. This adds a UUID label_value, making the tuple unique again. For the first case, you can also choose to just wait longer than 5 seconds between restarts.