add skeleton for e2e test

e2e/tests/test_e2e.py

@@ -268,6 +268,66 @@ class EndToEndTestCase(unittest.TestCase):
         self.assertEqual(0, len(jobs),
                          "Expected 0 logical backup jobs, found {}".format(len(jobs)))
 
+
+    @timeout_decorator.timeout(TEST_TIMEOUT_SEC)
+    def test_safe_pod_recreation(self):
+        '''
+        Operator skips pods re-creation if there is at least one pod for which patroni reports "creating replica" state
+        '''
+
+        k8s = self.k8s
+        nodes = self.get_pg_nodes()
+
+         # get test data for re-init
+        master = nodes[0]
+        cmd = 'pgbench -i -s 30 -n'
+        k8s.exec_into_pod(master, cmd)
+
+        # start reinit
+        replica = nodes[1][0]
+        cmd = 'patronictl reinit $SCOPE ' + replica
+        k8s.exec_into_pod(master, cmd)
+
+        # force rolling upgrade
+        patch = {
+            "spec": {
+                "resources": {
+                    "requests": {
+                        "cpu": "100m",
+                        "memory": "50Mi"
+                    },
+                    "limits": {
+                        "cpu": "200m",
+                        "memory": "200Mi"
+                    }
+                }
+            }
+        }
+        k8s.api.custom_objects_api.patch_namespaced_custom_object(
+            "acid.zalan.do", "v1", "default", "postgresqls", "acid-minimal-cluster", patch)
+
+        replica_state = ""
+        while replica_state != "running":
+            replica_state = k8s.get_patroni_state(self, replica)
+            time.sleep(k8s.RETRY_TIMEOUT_SEC)
+
+        # next Sync does the update
+        k8s.delete_operator_pod()
+        k8s.wait_for_pod_start('spilo-role=replica')
+
+        cluster_label = 'application=spilo,cluster-name=acid-minimal-cluster'
+        labels = 'spilo-role=master,' + cluster_label
+
+        pods = k8s.api.core_v1.list_namespaced_pod(
+            'default', label_selector=labels).items
+        self.assert_master_is_unique()
+        masterPod = pods[0]
+
+        self.assertEqual(masterPod.spec.containers[0].resources.requests['cpu'], "100m",
+                         "Expected CPU requests {}, found {}"
+                         .format("100cpu", masterPod.spec.containers[0].resources.requests['cpu']))
+
+
     @timeout_decorator.timeout(TEST_TIMEOUT_SEC)
     def test_min_resource_limits(self):
         '''
@@ -709,20 +769,26 @@ class K8s:
     def wait_for_logical_backup_job_creation(self):
         self.wait_for_logical_backup_job(expected_num_of_jobs=1)
 
-    def update_config(self, config_map_patch):
-        self.api.core_v1.patch_namespaced_config_map("postgres-operator", "default", config_map_patch)
-
+    def delete_operator_pod(self):
         operator_pod = self.api.core_v1.list_namespaced_pod(
             'default', label_selector="name=postgres-operator").items[0].metadata.name
         self.api.core_v1.delete_namespaced_pod(operator_pod, "default")  # restart reloads the conf
         self.wait_for_operator_pod_start()
 
+    def update_config(self, config_map_patch):
+        self.api.core_v1.patch_namespaced_config_map("postgres-operator", "default", config_map_patch)
+        self.delete_operator_pod()
+
     def create_with_kubectl(self, path):
         return subprocess.run(
             ["kubectl", "create", "-f", path],
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE)
 
+    def get_patroni_state(self, pod):
+        return pod.metadata.annotations["status"]["state"]
+
+
 
 if __name__ == '__main__':
     unittest.main()