Resource: Add deployment label for k8s resource. (#1943)

* Resource: Add deployment label for k8s resource.

* Add a missing annotation.

* Parse deployment name correctly.

Author: songy23

contrib/resource_util/src/main/java/io/opencensus/contrib/resource/util/K8sResource.java

@@ -19,8 +19,11 @@
 import static com.google.common.base.MoreObjects.firstNonNull;
 import static com.google.common.base.Preconditions.checkNotNull;
 
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Splitter;
 import io.opencensus.resource.Resource;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -57,6 +60,15 @@ public class K8sResource {
    */
   public static final String POD_NAME_KEY = "k8s.pod.name";
 
+  /**
+   * Key for the name of the deployment.
+   *
+   * @since 0.24
+   */
+  public static final String DEPLOYMENT_NAME_KEY = "k8s.deployment.name";
+
+  private static final Splitter splitter = Splitter.on('-');
+
   /**
    * Returns a {@link Resource} that describes Kubernetes deployment service.
    *
@@ -65,20 +77,60 @@ public class K8sResource {
    * @param podName the k8s pod name.
    * @return a {@link Resource} that describes a k8s container.
    * @since 0.20
+   * @deprecated in favor of {@link #create(String, String, String, String)}.
    */
+  @Deprecated
   public static Resource create(String clusterName, String namespace, String podName) {
+    return create(clusterName, namespace, podName, "");
+  }
+
+  /**
+   * Returns a {@link Resource} that describes Kubernetes deployment service.
+   *
+   * @param clusterName the k8s cluster name.
+   * @param namespace the k8s namespace.
+   * @param podName the k8s pod name.
+   * @param deploymentName the k8s deployment name.
+   * @return a {@link Resource} that describes a k8s container.
+   * @since 0.24
+   */
+  public static Resource create(
+      String clusterName, String namespace, String podName, String deploymentName) {
     Map<String, String> labels = new LinkedHashMap<String, String>();
     labels.put(CLUSTER_NAME_KEY, checkNotNull(clusterName, "clusterName"));
     labels.put(NAMESPACE_NAME_KEY, checkNotNull(namespace, "namespace"));
     labels.put(POD_NAME_KEY, checkNotNull(podName, "podName"));
+    labels.put(DEPLOYMENT_NAME_KEY, checkNotNull(deploymentName, "deploymentName"));
     return Resource.create(TYPE, labels);
   }
 
   static Resource detect() {
+    String podName = firstNonNull(System.getenv("HOSTNAME"), "");
+    String deploymentName = getDeploymentNameFromPodName(podName);
     return create(
         GcpMetadataConfig.getClusterName(),
         firstNonNull(System.getenv("NAMESPACE"), ""),
-        firstNonNull(System.getenv("HOSTNAME"), ""));
+        podName,
+        deploymentName);
+  }
+
+  @VisibleForTesting
+  static String getDeploymentNameFromPodName(String podName) {
+    StringBuilder deploymentName = new StringBuilder();
+    // Extract deployment name from the pod name. Pod name is created using
+    // format: [deployment-name]-[Random-String-For-ReplicaSet]-[Random-String-For-Pod]
+    List<String> parts = splitter.splitToList(podName);
+    if (parts.size() == 3) {
+      deploymentName.append(parts.get(0));
+    } else if (parts.size() > 3) { // Deployment name could also contain '-'
+      for (int i = 0; i < parts.size() - 2; i++) {
+        if (deploymentName.length() > 0) {
+          deploymentName.append('-');
+        }
+        deploymentName.append(parts.get(i));
+      }
+    }
+    return deploymentName.toString();
   }
 
   private K8sResource() {}

contrib/resource_util/src/test/java/io/opencensus/contrib/resource/util/K8sResourceTest.java

@@ -28,10 +28,11 @@
 public class K8sResourceTest {
   private static final String K8S_CLUSTER_NAME = "cluster";
   private static final String K8S_NAMESPACE_NAME = "namespace";
-  private static final String K8S_POD_NAME = "pod-id";
+  private static final String K8S_POD_NAME = "deployment-replica-pod";
+  private static final String K8S_DEPLOYMENT_NAME = "deployment";
 
   @Test
-  public void create_K8sContainerResourceTest() {
+  public void create_K8sContainerResourceTest_Deprecated() {
     Resource resource = K8sResource.create(K8S_CLUSTER_NAME, K8S_NAMESPACE_NAME, K8S_POD_NAME);
     assertThat(resource.getType()).isEqualTo(K8sResource.TYPE);
     assertThat(resource.getLabels())
@@ -41,6 +42,35 @@ public void create_K8sContainerResourceTest() {
             K8sResource.NAMESPACE_NAME_KEY,
             K8S_NAMESPACE_NAME,
             K8sResource.POD_NAME_KEY,
-            K8S_POD_NAME);
+            K8S_POD_NAME,
+            K8sResource.DEPLOYMENT_NAME_KEY,
+            "");
+  }
+
+  @Test
+  public void create_K8sContainerResourceTest() {
+    Resource resource =
+        K8sResource.create(K8S_CLUSTER_NAME, K8S_NAMESPACE_NAME, K8S_POD_NAME, K8S_DEPLOYMENT_NAME);
+    assertThat(resource.getType()).isEqualTo(K8sResource.TYPE);
+    assertThat(resource.getLabels())
+        .containsExactly(
+            K8sResource.CLUSTER_NAME_KEY,
+            K8S_CLUSTER_NAME,
+            K8sResource.NAMESPACE_NAME_KEY,
+            K8S_NAMESPACE_NAME,
+            K8sResource.POD_NAME_KEY,
+            K8S_POD_NAME,
+            K8sResource.DEPLOYMENT_NAME_KEY,
+            K8S_DEPLOYMENT_NAME);
+  }
+
+  @Test
+  public void getDeploymentNameFromPodName() {
+    assertThat(K8sResource.getDeploymentNameFromPodName(K8S_POD_NAME))
+        .isEqualTo(K8S_DEPLOYMENT_NAME);
+    assertThat(K8sResource.getDeploymentNameFromPodName("")).isEqualTo("");
+    assertThat(K8sResource.getDeploymentNameFromPodName("simple-name")).isEqualTo("");
+    assertThat(K8sResource.getDeploymentNameFromPodName("deployment-name-replica-pod"))
+        .isEqualTo("deployment-name");
   }
 }