Implement metrics export.

Author: michaelsafyan

opentelemetry-configurator-gcp/src/opentelemetry/configurator/gcp/metrics.py

@@ -1,5 +1,15 @@
+from opentelemetry import metrics as otel_metrics
+from opentelemetry.sdk import metrics as otel_metrics_sdk
+from opentelemetry.sdk.metrics import export as otel_metrics_sdk_export
+from opentelemetry.exporter import cloud_monitoring as otel_cloud_monitoring
 
 
 def configure_metrics_exporter(resource=None):
-    # TODO:...
-    pass
+    provider = otel_metrics_sdk.MeterProvider(
+        metric_readers=[
+            otel_metrics_sdk_export.PeriodicExportingMetricReader(
+                otel_cloud_monitoring.CloudMonitoringMetricsExporter()
+            ),
+        ],
+        resource=resource)
+    otel_metrics.set_meter_provider(provider)