def get_agent_pod_host(self, return_host_name=False):
"""Obtain host the agent is running on in Kubernetes.
Used when trying to connect to services running on the node (Kubelet, cAdvisor)
"""
# Get pod name and namespace from environment variables
pod_name = os.environ.get("AGENT_POD_NAME")
pod_namespace = os.environ.get("AGENT_POD_NAMESPACE")
if not pod_name:
raise exceptions.MissingEnvironmentVariables(
"pod_name is not set as environment variables cannot derive"
" host from Kubernetes API")
if not pod_namespace:
raise exceptions.MissingEnvironmentVariables(
"pod_namespace is not set as environment variables cannot "
"derive host from Kubernetes API")
pod_url = "/api/v1/namespaces/{}/pods/{}".format(pod_namespace, pod_name)
try:
agent_pod = self.get_request(pod_url)
except Exception as e:
exception_message = "Could not get agent pod from Kubernetes API" \
" to get host IP with error - {}".format(e)
log.exception(exception_message)
raise exceptions.KubernetesAPIConnectionError(exception_message)
if not return_host_name:
return agent_pod['status']['hostIP']
else:
return agent_pod['spec']['nodeName']
def get_request(self, request_endpoint, as_json=True, retried=False):
"""Sends request to Kubernetes API with given endpoint.
Will retry the request once, with updated token/cert, if unauthorized.
"""
api_url = self.api_url
if api_url[-1] == '/':
api_url = api_url[:-1]
if request_endpoint[0] == '/':
request_endpoint = request_endpoint[1:]
request_url = "{}/{}".format(api_url, request_endpoint)
result = requests.get(request_url,
timeout=self.connection_timeout,
headers=self.api_request_header,
verify=self.api_verify)
if result.status_code >= 300:
if result.status_code == 401 and not retried:
log.info("Could not authenticate with Kubernetes API at the"
" first time. Rereading in cert and token.")
self._set_kubernetes_service_account_info()
return self.get_request(request_endpoint, as_json=as_json,
retried=True)
exception_message = "Could not obtain data from {} with the " \
"given status code {} and return text {}".\
format(request_url, result.status_code, result.text)
raise exceptions.KubernetesAPIConnectionError(exception_message)
return result.json() if as_json else result