Checks for outstanding pod creation requests so that we don't create extraneous pods

Author: GaneshSPatil

src/main/java/cd/go/contrib/elasticagent/KubernetesAgentInstances.java

@@ -16,6 +16,7 @@
 
 package cd.go.contrib.elasticagent;
 
+import cd.go.contrib.elasticagent.model.JobIdentifier;
 import cd.go.contrib.elasticagent.requests.CreateAgentRequest;
 import io.fabric8.kubernetes.api.model.Pod;
 import io.fabric8.kubernetes.api.model.PodList;
@@ -55,13 +56,29 @@ public KubernetesAgentInstances(KubernetesClientFactory factory, KubernetesInsta
 
     @Override
     public KubernetesInstance create(CreateAgentRequest request, PluginSettings settings, PluginRequest pluginRequest) throws Exception {
+        JobIdentifier jobIdentifier = request.jobIdentifier();
+        if (isAgentCreatedForJob(jobIdentifier.getJobId())) {
+            LOG.warn("[Create Agent Request] Request for creating an agent for Job Identifier [" + jobIdentifier + "] has already been scheduled. Skipping current request.");
+            return null;
+        }
+
         KubernetesClient client = factory.kubernetes(settings);
         KubernetesInstance instance = kubernetesInstanceFactory.create(request, settings, client, pluginRequest, isUsingPodYaml(request));
         register(instance);
 
         return instance;
     }
 
+    private boolean isAgentCreatedForJob(Long jobId) {
+        for (KubernetesInstance instance : instances.values()) {
+            if (instance.jobId().equals(jobId)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     private boolean isUsingPodYaml(CreateAgentRequest request) {
         return Boolean.valueOf(request.properties().get(SPECIFIED_USING_POD_CONFIGURATION.getKey()));
     }
@@ -133,10 +150,6 @@ public KubernetesInstance find(String agentId) {
         return instances.get(agentId);
     }
 
-    public boolean hasInstance(String agentId) {
-        return instances.containsKey(agentId);
-    }
-
     private void register(KubernetesInstance instance) {
         instances.put(instance.name(), instance);
     }

src/main/java/cd/go/contrib/elasticagent/KubernetesInstance.java

@@ -56,4 +56,8 @@ public String environment() {
     public Map<String, String> getInstanceProperties() {
         return properties;
     }
+
+    public Long jobId() {
+        return jobId;
+    }
 }

src/test/java/cd/go/contrib/elasticagent/KubernetesAgentInstancesTest.java

@@ -51,8 +51,6 @@ public class KubernetesAgentInstancesTest {
     @Mock
     PluginRequest mockPluginRequest;
 
-    @Mock
-    PodOperationsImpl mockPods;
     private HashMap<String, String> testProperties;
 
     @Before
@@ -61,11 +59,13 @@ public void setUp() throws Exception {
         testProperties = new HashMap<>();
         when(mockCreateAgentRequest.properties()).thenReturn(testProperties);
         when(factory.kubernetes(mockPluginSettings)).thenReturn(mockKubernetesClient);
+        JobIdentifier jobId = new JobIdentifier("test", 1L, "Test pipeline", "test name", "1", "test job", 100L);
+        when(mockCreateAgentRequest.jobIdentifier()).thenReturn(jobId);
     }
 
     @Test
     public void shouldCreateKubernetesPodUsingPodYamlAndCacheCreatedInstance() throws Exception {
-        KubernetesInstance kubernetesInstance = new KubernetesInstance(new DateTime(), "test", "test-agent", new HashMap<>(), null);
+        KubernetesInstance kubernetesInstance = new KubernetesInstance(new DateTime(), "test", "test-agent", new HashMap<>(), 100L);
         when(mockKubernetesInstanceFactory.create(mockCreateAgentRequest, mockPluginSettings, mockKubernetesClient, mockPluginRequest, true)).
                 thenReturn(kubernetesInstance);
 
@@ -78,12 +78,30 @@ public void shouldCreateKubernetesPodUsingPodYamlAndCacheCreatedInstance() throw
 
     @Test
     public void shouldCreateKubernetesPodAndCacheCreatedInstance() throws Exception {
-        KubernetesInstance kubernetesInstance = new KubernetesInstance(new DateTime(), "test", "test-agent", new HashMap<>(), null);
+        KubernetesInstance kubernetesInstance = new KubernetesInstance(new DateTime(), "test", "test-agent", new HashMap<>(), 100L);
         when(mockKubernetesInstanceFactory.create(mockCreateAgentRequest, mockPluginSettings, mockKubernetesClient, mockPluginRequest, false)).
                 thenReturn(kubernetesInstance);
         testProperties.put("SpecifiedUsingPodConfiguration", "false");
         KubernetesAgentInstances agentInstances = new KubernetesAgentInstances(factory, mockKubernetesInstanceFactory);
         KubernetesInstance instance = agentInstances.create(mockCreateAgentRequest, mockPluginSettings, mockPluginRequest);
         assertTrue(agentInstances.instanceExists(instance));
     }
+
+    @Test
+    public void shouldNotCreatePodWhenOutstandingRequestsExistForJobs() throws Exception {
+        KubernetesInstance kubernetesInstance = new KubernetesInstance(new DateTime(), "test", "test-agent", new HashMap<>(), 100L);
+        when(mockKubernetesInstanceFactory.create(mockCreateAgentRequest, mockPluginSettings, mockKubernetesClient, mockPluginRequest, false)).
+                thenReturn(kubernetesInstance);
+        testProperties.put("SpecifiedUsingPodConfiguration", "false");
+
+        KubernetesAgentInstances agentInstances = new KubernetesAgentInstances(factory, mockKubernetesInstanceFactory);
+        JobIdentifier jobId = new JobIdentifier("test", 1L, "Test pipeline", "test name", "1", "test job", 100L);
+        when(mockCreateAgentRequest.jobIdentifier()).thenReturn(jobId);
+        agentInstances.create(mockCreateAgentRequest, mockPluginSettings, mockPluginRequest);
+        verify(mockKubernetesInstanceFactory, times(1)).create(any(), any(), any(), any(), any());
+        reset(mockKubernetesInstanceFactory);
+
+        agentInstances.create(mockCreateAgentRequest, mockPluginSettings, mockPluginRequest);
+        verify(mockKubernetesInstanceFactory, times(0)).create(any(), any(), any(), any(), any());
+    }
 }

src/test/java/cd/go/contrib/elasticagent/executors/ServerPingRequestExecutorTest.java

@@ -131,7 +131,7 @@ public void testShouldTerminateInstancesThatNeverAutoRegistered() throws Excepti
         verifyNoMoreInteractions(pluginRequest);
 
         new ServerPingRequestExecutor(agentInstances, pluginRequest).execute();
-        assertFalse(agentInstances.hasInstance(container.name()));
+        assertFalse(agentInstances.instanceExists(container));
     }
 
     @Test