ric_robot_suite/ric-python-utils/ricutils/KubernetesEntity.py

   1 #   Copyright (c) 2019 AT&T Intellectual Property.
   2 #   Copyright (c) 2019 Nokia.
   3 #
   4 #   Licensed under the Apache License, Version 2.0 (the "License");
   5 #   you may not use this file except in compliance with the License.
   6 #   You may obtain a copy of the License at
   7 #
   8 #       http://www.apache.org/licenses/LICENSE-2.0
   9 #
  10 #   Unless required by applicable law or agreed to in writing, software
  11 #   distributed under the License is distributed on an "AS IS" BASIS,
  12 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 #   See the License for the specific language governing permissions and
  14 #   limitations under the License.
  15
  16 from kubernetes import client, config
  17 import string
  18 import random
  19 import time
  20 import sys
  21
  22 # This library provides a massively-simplified interface to the kubernetes
  23 # API library to reduce bloat in robot tests.
  24
  25 class KubernetesEntity(object):
  26  def __init__(self, namespace):
  27   self._ns = namespace
  28   self._annotationGensym = ''.join(random.choice(string.ascii_letters) for _ in range(16))
  29
  30   # FIXME: this needs to be configurable.
  31   config.load_kube_config()
  32
  33   self._k8sApp = client.AppsV1Api()
  34   self._k8sCore = client.CoreV1Api()
  35   self._k8sEV1B1 = client.ExtensionsV1beta1Api()
  36
  37  def Deployment(self, name):
  38   # this will throw kubernetes.client.rest.ApiException if
  39   # the deployment doesn't exist.  we'll let robot cope with
  40   # that.
  41
  42   # calling code will most likely want to check that
  43   # deploy.status.replicas == deploy.status.available_replicas
  44   return self._k8sApp.read_namespaced_deployment(namespace=self._ns,
  45                                                  name=name)
  46
  47  def Service(self, name):
  48   # as above, we'll rely on this to throw if the svc dne.
  49
  50   # not much to check directly here.  calling code will want
  51   # to hit svc.spec.cluster_ip:r.spec.ports[0..n] with some
  52   # sort of health-check request
  53   return self._k8sCore.read_namespaced_service(namespace=self._ns,
  54                                                name=name)
  55
  56  def Pod(self, name):
  57   return self._k8sCore.read_namespaced_pod(namespace=self._ns,
  58                                            name=name)
  59
  60  def Redeploy(self, name, wait=True, timeout=30):
  61   # restart an existing deployment by doing a nonsense update
  62   # to its spec.
  63   body = {'spec':
  64           {'template':
  65            {'metadata':
  66             {'annotations':
  67              { self._annotationGensym: str(time.time()) }}}}}
  68
  69   r = self._k8sEV1B1.patch_namespaced_deployment(namespace=self._ns,
  70                                                  name=name,
  71                                                  body=body)
  72   if wait:
  73    r = self.WaitForDeployment(name, timeout)
  74   return r
  75
  76  def WaitForDeployment(self, name, timeout=30):
  77   # block until a deployment is available
  78   while timeout > 0:
  79    dep = self.Deployment(name)
  80    if dep and dep.status.conditions[-1].type == 'Available':
  81     return True
  82    time.sleep(1)
  83    timeout -= 1
  84   raise TimeoutError('Kubernetes timeout waiting for ' + name + ' to become available')
  85
  86  def RetrievePodsForDeployment(self, name):
  87   # return the pod names associated with a deployment
  88   d = self.Deployment(name)
  89   labels = d.spec.selector.match_labels
  90   pods = self._k8sCore.list_namespaced_pod(self._ns,
  91                                            label_selector=",".join(map(lambda k: k + "=" + labels[k],
  92                                                                        labels)))
  93   return map(lambda i: i.metadata.name, pods.items)
  94
  95  def RetrieveLogForPod(self, pod, container='', tail=sys.maxsize):
  96   # not really an "entity" thing per se, but.
  97   # kinda want to include timestamps, but i don't have a use case for them.
  98   return self._k8sCore.read_namespaced_pod_log(namespace=self._ns,
  99                                                name=pod,
 100                                                container=container,
 101                                                tail_lines=tail).split('\n')[0:-1]