Description
I noticed that calling Spanner.getDatabaseClient with a non-existent database and then trying to read from the database can cause new client IDs to appear in the OpenCensus session metrics. The client IDs for the non-existent database seem problematic because they can cause the size of the metrics to grow.
Here is a simplified reproduction:
google-cloud-spanner version: 1.54.0
opencensus-java version: 0.26.0
import com.google.cloud.spanner.DatabaseId;
import com.google.cloud.spanner.InstanceConfigId;
import com.google.cloud.spanner.InstanceId;
import com.google.cloud.spanner.InstanceInfo;
import com.google.cloud.spanner.Key;
import com.google.cloud.spanner.Spanner;
import com.google.cloud.spanner.SpannerOptions;
import io.opencensus.exporter.stats.stackdriver.StackdriverStatsExporter;
import java.util.Arrays;
import org.junit.Test;
public class ClientIdTest {
@Test
public void testClientId() throws Exception {
StackdriverStatsExporter.createAndRegister();
Spanner spanner = SpannerOptions.getDefaultInstance().getService();
String projectId = spanner.getOptions().getProjectId();
InstanceId instanceId = InstanceId.of(projectId, "my-instance");
InstanceConfigId instanceConfigId = InstanceConfigId.of(projectId, "regional-us-central1");
spanner
.getInstanceAdminClient()
.createInstance(
InstanceInfo.newBuilder(instanceId)
.setInstanceConfigId(instanceConfigId)
.setDisplayName("my-instance")
.setNodeCount(1)
.build())
.get();
DatabaseId databaseId = DatabaseId.of(instanceId, "my-database");
for (int i = 0; i < 100; i++) {
try {
spanner
.getDatabaseClient(databaseId)
.singleUse()
.readRow("MyTable", Key.of(0), Arrays.asList("MyColumn"));
} catch (Exception e) {
// ignore
}
}
Thread.sleep(300_000);
}
}The metrics exported to Stackdriver contain 100 client IDs. For example, here is in_use_sessions:
