kubernetes/readiness/src/main/scripts/ready.py

   1 #!/usr/bin/env python
   2 import getopt
   3 import logging
   4 import os
   5 import sys
   6 import time
   7 import random
   8
   9 from kubernetes import client
  10
  11 # extract env variables.
  12 namespace = os.environ['NAMESPACE']
  13 cert = os.environ['CERT']
  14 host = os.environ['KUBERNETES_SERVICE_HOST']
  15 token_path = os.environ['TOKEN']
  16
  17 with open(token_path, 'r') as token_file:
  18     token = token_file.read().replace('\n', '')
  19
  20 # setup logging
  21 log = logging.getLogger(__name__)
  22 handler = logging.StreamHandler(sys.stdout)
  23 formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
  24 handler.setFormatter(formatter)
  25 handler.setLevel(logging.INFO)
  26 log.addHandler(handler)
  27 log.setLevel(logging.INFO)
  28
  29 configuration = client.Configuration()
  30 configuration.host = "https://" + host
  31 configuration.ssl_ca_cert = cert
  32 configuration.api_key['authorization'] = token
  33 configuration.api_key_prefix['authorization'] = 'Bearer'
  34 coreV1Api = client.CoreV1Api(client.ApiClient(configuration))
  35 api_instance = client.ExtensionsV1beta1Api(client.ApiClient(configuration))
  36 api = client.AppsV1beta1Api(client.ApiClient(configuration))
  37 batchV1Api = client.BatchV1Api(client.ApiClient(configuration))
  38
  39
  40 def is_job_complete(job_name):
  41     complete = False
  42     log.info("Checking if " + job_name + "  is complete")
  43     try:
  44         response = batchV1Api.read_namespaced_job_status(job_name, namespace)
  45         if response.status.succeeded == 1:
  46             job_status_type = response.status.conditions[0].type
  47             if job_status_type == "Complete":
  48                 complete = True
  49                 log.info(job_name + " is complete")
  50             else:
  51                 log.info(job_name + " is not complete")
  52         else:
  53             log.info(job_name + " has not succeeded yet")
  54         return complete
  55     except Exception as e:
  56         log.error("Exception when calling read_namespaced_job_status: %s\n" % e)
  57
  58
  59 def wait_for_statefulset_complete(statefulset_name):
  60     try:
  61         response = api.read_namespaced_stateful_set(statefulset_name, namespace)
  62         s = response.status
  63         if (s.replicas == response.spec.replicas and
  64                 s.ready_replicas == response.spec.replicas and
  65                 s.observed_generation == response.metadata.generation):
  66             log.info("Statefulset " + statefulset_name + "  is ready")
  67             return True
  68         else:
  69             log.info("Statefulset " + statefulset_name + "  is not ready")
  70         return False
  71     except Exception as e:
  72         log.error("Exception when waiting for Statefulset status: %s\n" % e)
  73
  74
  75 def wait_for_deployment_complete(deployment_name):
  76     try:
  77         response = api.read_namespaced_deployment(deployment_name, namespace)
  78         s = response.status
  79         if (s.unavailable_replicas is None and
  80                 ( s.updated_replicas is None or s.updated_replicas == response.spec.replicas ) and
  81                 s.replicas == response.spec.replicas and
  82                 s.ready_replicas == response.spec.replicas and
  83                 s.observed_generation == response.metadata.generation):
  84             log.info("Deployment " + deployment_name + "  is ready")
  85             return True
  86         else:
  87             log.info("Deployment " + deployment_name + "  is not ready")
  88         return False
  89     except Exception as e:
  90         log.error("Exception when waiting for deployment status: %s\n" % e)
  91
  92
  93 def wait_for_daemonset_complete(daemonset_name):
  94     try:
  95         response = api_instance.read_namespaced_daemon_set(daemonset_name, namespace)
  96         s = response.status
  97         if s.desired_number_scheduled == s.number_ready:
  98             log.info("DaemonSet: " + str(s.number_ready) + "/" + str(s.desired_number_scheduled) + " nodes ready --> " + daemonset_name + " is ready")
  99             return True
 100         else:
 101             log.info("DaemonSet: " + str(s.number_ready) + "/" + str(s.desired_number_scheduled) + " nodes ready --> " + daemonset_name + " is not ready")
 102             return False
 103     except Exception as e:
 104         log.error("Exception when waiting for DaemonSet status: %s\n" % e)
 105
 106
 107 def is_ready(container_name):
 108     ready = False
 109     log.info("Checking if " + container_name + "  is ready")
 110     try:
 111         response = coreV1Api.list_namespaced_pod(namespace=namespace,
 112                                                  watch=False)
 113         for i in response.items:
 114             # container_statuses can be None, which is non-iterable.
 115             if i.status.container_statuses is None:
 116                 continue
 117             for s in i.status.container_statuses:
 118                 if s.name == container_name:
 119                     name = read_name(i)
 120                     if i.metadata.owner_references[0].kind == "StatefulSet":
 121                         ready = wait_for_statefulset_complete(name)
 122                     elif i.metadata.owner_references[0].kind == "ReplicaSet":
 123                         deployment_name = get_deployment_name(name)
 124                         ready = wait_for_deployment_complete(deployment_name)
 125                     elif i.metadata.owner_references[0].kind == "Job":
 126                         ready = is_job_complete(name)
 127                     elif i.metadata.owner_references[0].kind == "DaemonSet":
 128                         ready = wait_for_daemonset_complete(i.metadata.owner_references[0].name)
 129
 130                     return ready
 131
 132                 else:
 133                     continue
 134         return ready
 135     except Exception as e:
 136         log.error("Exception when calling list_namespaced_pod: %s\n" % e)
 137
 138
 139 def read_name(item):
 140     return item.metadata.owner_references[0].name
 141
 142
 143 def get_deployment_name(replicaset):
 144     api_response = api_instance.read_namespaced_replica_set_status(replicaset,
 145                                                                    namespace)
 146     deployment_name = read_name(api_response)
 147     return deployment_name
 148
 149
 150 DEF_TIMEOUT = 10
 151 DESCRIPTION = "Kubernetes container readiness check utility"
 152 USAGE = "Usage: ready.py [-t <timeout>] -c <container_name> " \
 153         "[-c <container_name> ...]\n" \
 154         "where\n" \
 155         "<timeout> - wait for container readiness timeout in min, " \
 156         "default is " + str(DEF_TIMEOUT) + "\n" \
 157         "<container_name> - name of the container to wait for\n"
 158
 159
 160 def main(argv):
 161     # args are a list of container names
 162     container_names = []
 163     timeout = DEF_TIMEOUT
 164     try:
 165         opts, args = getopt.getopt(argv, "hc:t:", ["container-name=",
 166                                                    "timeout=",
 167                                                    "help"])
 168         for opt, arg in opts:
 169             if opt in ("-h", "--help"):
 170                 print("%s\n\n%s" % (DESCRIPTION, USAGE))
 171                 sys.exit()
 172             elif opt in ("-c", "--container-name"):
 173                 container_names.append(arg)
 174             elif opt in ("-t", "--timeout"):
 175                 timeout = float(arg)
 176     except (getopt.GetoptError, ValueError) as e:
 177         print("Error parsing input parameters: %s\n" % e)
 178         print(USAGE)
 179         sys.exit(2)
 180     if container_names.__len__() == 0:
 181         print("Missing required input parameter(s)\n")
 182         print(USAGE)
 183         sys.exit(2)
 184
 185     for container_name in container_names:
 186         timeout = time.time() + timeout * 60
 187         while True:
 188             ready = is_ready(container_name)
 189             if ready is True:
 190                 break
 191             elif time.time() > timeout:
 192                 log.warning("timed out waiting for '" + container_name +
 193                             "' to be ready")
 194                 exit(1)
 195             else:
 196                 # spread in time potentially parallel execution in multiple
 197                 # containers
 198                 time.sleep(random.randint(5, 11))
 199
 200
 201 if __name__ == "__main__":
 202     main(sys.argv[1:])
 203