Initial commit of script

Add the script and the Dockerfile
Make the script pass pylint (one issue left)
Make Dockerfile from base ONAP image

Issue-ID: OOM-2418
Issue-ID: OOM-761
Signed-off-by: Sylvain Desbureaux <sylvain.desbureaux@orange.com>
Change-Id: Ia93e3e85a16c764eca0c14af2dbe166117ea769a

1 files changed, 309 insertions, 0 deletions

diff --git a/ready.py b/ready.py
new file mode 100755
index 0000000..0640ed5
--- /dev/null
+++ b/ready.py
@@ -0,0 +1,309 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# Copyright © 2020 Orange
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Kubernetes readiness check.
+
+Checks if a container is ready or if a job is finished.
+The check is done according to the name of the container, not the name of
+its parent (Job, Deployment, StatefulSet, DaemonSet).
+"""
+
+import getopt
+import logging
+import os
+import sys
+import time
+import random
+
+from kubernetes import client
+from kubernetes.client.rest import ApiException
+
+# extract env variables.
+namespace = os.environ['NAMESPACE']
+cert = os.environ['CERT']
+host = os.environ['KUBERNETES_SERVICE_HOST']
+token_path = os.environ['TOKEN']
+
+with open(token_path, 'r') as token_file:
+    token = token_file.read().replace('\n', '')
+
+# setup logging
+log = logging.getLogger(__name__)
+handler = logging.StreamHandler(sys.stdout)
+formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
+handler.setFormatter(formatter)
+handler.setLevel(logging.INFO)
+log.addHandler(handler)
+log.setLevel(logging.INFO)
+
+configuration = client.Configuration()
+configuration.host = "https://" + host
+configuration.ssl_ca_cert = cert
+configuration.api_key['authorization'] = token
+configuration.api_key_prefix['authorization'] = 'Bearer'
+coreV1Api = client.CoreV1Api(client.ApiClient(configuration))
+api_instance = client.ExtensionsV1beta1Api(client.ApiClient(configuration))
+api = client.AppsV1beta1Api(client.ApiClient(configuration))
+batchV1Api = client.BatchV1Api(client.ApiClient(configuration))
+
+
+def is_job_complete(job_name):
+    """
+    Check if Job is complete.
+
+    Args:
+        job_name (str): the name of the Job.
+
+    Returns:
+        True if job is complete, false otherwise
+    """
+    complete = False
+    log.info("Checking if %s is complete", job_name)
+    try:
+        response = batchV1Api.read_namespaced_job_status(job_name, namespace)
+        if response.status.succeeded == 1:
+            job_status_type = response.status.conditions[0].type
+            if job_status_type == "Complete":
+                complete = True
+                log.info("%s is complete", job_name)
+            else:
+                log.info("%s is NOT complete", job_name)
+        else:
+            log.info("%s has not succeeded yet", job_name)
+    except ApiException as exc:
+        log.error("Exception when calling read_namespaced_job_status: %s\n",
+                  exc)
+    return complete
+
+
+def wait_for_statefulset_complete(statefulset_name):
+    """
+    Check if StatefulSet is running.
+
+    Args:
+        statefulset_name (str): the name of the StatefulSet.
+
+    Returns:
+        True if StatefulSet is running, false otherwise
+    """
+    complete = False
+    try:
+        response = api.read_namespaced_stateful_set(statefulset_name,
+                                                    namespace)
+        status = response.status
+        if (status.replicas == response.spec.replicas and
+                status.ready_replicas == response.spec.replicas and
+                status.observed_generation == response.metadata.generation):
+            log.info("Statefulset %s is ready", statefulset_name)
+            complete = True
+        else:
+            log.info("Statefulset %s is NOT ready", statefulset_name)
+    except ApiException as exc:
+        log.error("Exception when waiting for Statefulset status: %s\n", exc)
+    return complete
+
+
+def wait_for_deployment_complete(deployment_name):
+    """
+    Check if Deployment is running.
+
+    Args:
+        deployment_name (str): the name of the Deployment.
+
+    Returns:
+        True if Deployment is running, false otherwise
+    """
+    complete = False
+    try:
+        response = api.read_namespaced_deployment(deployment_name, namespace)
+        status = response.status
+        if (status.unavailable_replicas is None and
+                (status.updated_replicas is None or
+                 status.updated_replicas == response.spec.replicas) and
+                status.replicas == response.spec.replicas and
+                status.ready_replicas == response.spec.replicas and
+                status.observed_generation == response.metadata.generation):
+            log.info("Deployment %s is ready", deployment_name)
+            complete = True
+        else:
+            log.info("Deployment %s is NOT ready", deployment_name)
+    except ApiException as exc:
+        log.error("Exception when waiting for deployment status: %s\n", exc)
+    return complete
+
+
+def wait_for_daemonset_complete(daemonset_name):
+    """
+    Check if DaemonSet is running.
+
+    Args:
+        daemonset_name (str): the name of the DaemonSet.
+
+    Returns:
+        True if DaemonSet is running, false otherwise
+    """
+    complete = False
+    try:
+        response = api_instance.read_namespaced_daemon_set(
+            daemonset_name, namespace)
+        status = response.status
+        if status.desired_number_scheduled == status.number_ready:
+            log.info("DaemonSet: %s/%s nodes ready --> %s is ready",
+                     status.number_ready, status.desired_number_scheduled,
+                     daemonset_name)
+            complete = True
+        else:
+            log.info("DaemonSet: %s/%s nodes ready --> %s is NOT ready",
+                     status.number_ready, status.desired_number_scheduled,
+                     daemonset_name)
+    except ApiException as exc:
+        log.error("Exception when waiting for DaemonSet status: %s\n", exc)
+    return complete
+
+
+def is_ready(container_name):
+    """
+    Check if a container is ready.
+
+    For a container owned by a Job, it means the Job is complete.
+    Otherwise, it means the parent (Deployment, StatefulSet, DaemonSet) is
+    running with the right number of replicas
+
+    Args:
+        container_name (str): the name of the container.
+
+    Returns:
+        True if container is ready, false otherwise
+    """
+    ready = False
+    log.info("Checking if %s is ready", container_name)
+    try:
+        response = coreV1Api.list_namespaced_pod(namespace=namespace,
+                                                 watch=False)
+        for item in response.items:
+            # container_statuses can be None, which is non-iterable.
+            if item.status.container_statuses is None:
+                continue
+            for container in item.status.container_statuses:
+                if container.name == container_name:
+                    name = read_name(item)
+                    if item.metadata.owner_references[0].kind == "StatefulSet":
+                        ready = wait_for_statefulset_complete(name)
+                    elif item.metadata.owner_references[0].kind == "ReplicaSet":
+                        deployment_name = get_deployment_name(name)
+                        ready = wait_for_deployment_complete(deployment_name)
+                    elif item.metadata.owner_references[0].kind == "Job":
+                        ready = is_job_complete(name)
+                    elif item.metadata.owner_references[0].kind == "DaemonSet":
+                        ready = wait_for_daemonset_complete(
+                            item.metadata.owner_references[0].name)
+                    return ready
+    except ApiException as exc:
+        log.error("Exception when calling list_namespaced_pod: %s\n", exc)
+    return ready
+
+
+def read_name(item):
+    """
+    Return the name of the owner's item.
+
+    Args:
+        item (str): the item.
+
+    Returns:
+        the name of first owner's item
+    """
+    return item.metadata.owner_references[0].name
+
+
+def get_deployment_name(replicaset):
+    """
+    Return the name of the Deployment owning the ReplicatSet.
+
+    Args:
+        replicaset (str): the ReplicatSet.
+
+    Returns:
+        the name of the Deployment owning the ReplicatSet
+    """
+    api_response = api_instance.read_namespaced_replica_set_status(replicaset,
+                                                                   namespace)
+    deployment_name = read_name(api_response)
+    return deployment_name
+
+
+DEF_TIMEOUT = 10
+DESCRIPTION = "Kubernetes container readiness check utility"
+USAGE = "Usage: ready.py [-t <timeout>] -c <container_name> " \
+        "[-c <container_name> ...]\n" \
+        "where\n" \
+        "<timeout> - wait for container readiness timeout in min, " \
+        "default is " + str(DEF_TIMEOUT) + "\n" \
+        "<container_name> - name of the container to wait for\n"
+
+
+def main(argv):
+    """
+    Checks if a container is ready or if a job is finished.
+    The check is done according to the name of the container, not the name of
+    its parent (Job, Deployment, StatefulSet, DaemonSet).
+
+    Args:
+        argv: the command line
+    """
+    # args are a list of container names
+    container_names = []
+    timeout = DEF_TIMEOUT
+    try:
+        opts, _args = getopt.getopt(argv, "hc:t:", ["container-name=",
+                                                    "timeout=",
+                                                    "help"])
+        for opt, arg in opts:
+            if opt in ("-h", "--help"):
+                print("{}\n\n{}".format(DESCRIPTION, USAGE))
+                sys.exit()
+            elif opt in ("-c", "--container-name"):
+                container_names.append(arg)
+            elif opt in ("-t", "--timeout"):
+                timeout = float(arg)
+    except (getopt.GetoptError, ValueError) as exc:
+        print("Error parsing input parameters: {}\n".format(exc))
+        print(USAGE)
+        sys.exit(2)
+    if container_names.__len__() == 0:
+        print("Missing required input parameter(s)\n")
+        print(USAGE)
+        sys.exit(2)
+
+    for container_name in container_names:
+        timeout = time.time() + timeout * 60
+        while True:
+            ready = is_ready(container_name)
+            if ready is True:
+                break
+            if time.time() > timeout:
+                log.warning("timed out waiting for '%s' to be ready",
+                            container_name)
+                sys.exit(1)
+            else:
+                # spread in time potentially parallel execution in multiple
+                # containers
+                time.sleep(random.randint(5, 11))
+
+
+if __name__ == "__main__":
+    main(sys.argv[1:])