954e338d17
This patch adds mairadb controller that is responsible to mark one ready pod as mariadb_role: primary to forward all traffic to it. This will allow to drop nginx ingress controller which adds extra hops between client and server and uses heavy customized nginx templates. Change-Id: I3b29bc2029bfd39754516e73a09e4e14c52ccc99
113 lines
3.0 KiB
Smarty
113 lines
3.0 KiB
Smarty
#!/usr/bin/env python3
|
|
|
|
"""
|
|
Mariadb controller
|
|
|
|
The script is responsible for set mariadb_role: primary to first
|
|
active pod in mariadb deployment.
|
|
|
|
Env variables:
|
|
MARIADB_CONTROLLER_DEBUG: Flag to enable debug when set to 1.
|
|
MARIADB_CONTROLLER_CHECK_PODS_DELAY: The delay between check pod attempts.
|
|
MARIADB_CONTROLLER_PYKUBE_REQUEST_TIMEOUT: The timeout for kubernetes http session
|
|
MARIADB_CONTROLLER_PODS_NAMESPACE: The namespace to look for mariadb pods.
|
|
MARIADB_MASTER_SERVICE_NAME: The name of master service for mariadb.
|
|
|
|
Changelog:
|
|
0.1.0: Initial varsion
|
|
"""
|
|
|
|
|
|
import logging
|
|
import os
|
|
import sys
|
|
import time
|
|
|
|
import pykube
|
|
|
|
MARIADB_CONTROLLER_DEBUG = os.getenv("MARIADB_CONTROLLER_DEBUG")
|
|
MARIADB_CONTROLLER_CHECK_PODS_DELAY = int(
|
|
os.getenv("MARIADB_CONTROLLER_CHECK_PODS_DELAY", 10)
|
|
)
|
|
MARIADB_CONTROLLER_PYKUBE_REQUEST_TIMEOUT = int(
|
|
os.getenv("MARIADB_CONTROLLER_PYKUBE_REQUEST_TIMEOUT", 60)
|
|
)
|
|
MARIADB_CONTROLLER_PODS_NAMESPACE = os.getenv(
|
|
"MARIADB_CONTROLLER_PODS_NAMESPACE", "openstack"
|
|
)
|
|
MARIADB_MASTER_SERVICE_NAME = os.getenv(
|
|
"MARIADB_MASTER_SERVICE_NAME", "mariadb"
|
|
)
|
|
|
|
log_level = "DEBUG" if MARIADB_CONTROLLER_DEBUG else "INFO"
|
|
logging.basicConfig(
|
|
stream=sys.stdout,
|
|
format="%(asctime)s %(levelname)s %(name)s %(message)s",
|
|
datefmt="%Y-%m-%d %H:%M:%S",
|
|
)
|
|
LOG = logging.getLogger("mariadb-controller")
|
|
|
|
LOG.setLevel(log_level)
|
|
|
|
|
|
def login():
|
|
config = pykube.KubeConfig.from_env()
|
|
client = pykube.HTTPClient(
|
|
config=config, timeout=MARIADB_CONTROLLER_PYKUBE_REQUEST_TIMEOUT
|
|
)
|
|
LOG.info(f"Created k8s api client from context {config.current_context}")
|
|
return client
|
|
|
|
|
|
api = login()
|
|
|
|
|
|
def resource_list(klass, selector, namespace=None):
|
|
return klass.objects(api).filter(namespace=namespace, selector=selector)
|
|
|
|
|
|
def get_mariadb_pods():
|
|
sorted_pods = sorted(
|
|
resource_list(
|
|
pykube.Pod,
|
|
{"application": "mariadb", "component": "server"},
|
|
MARIADB_CONTROLLER_PODS_NAMESPACE,
|
|
).iterator(),
|
|
key=lambda i: i.name,
|
|
)
|
|
return sorted_pods
|
|
|
|
|
|
def get_mariadb_master_service(namespace):
|
|
return pykube.Service.objects(api).filter(namespace=namespace).get(name=MARIADB_MASTER_SERVICE_NAME)
|
|
|
|
|
|
def link_master_service(pod):
|
|
svc = get_mariadb_master_service(MARIADB_CONTROLLER_PODS_NAMESPACE)
|
|
svc.reload()
|
|
if svc.obj['spec']['selector'].get('statefulset.kubernetes.io/pod-name') == pod.name:
|
|
LOG.debug(f"Nothing to do, master service points to {pod.name}")
|
|
else:
|
|
svc.obj['spec']['selector']['statefulset.kubernetes.io/pod-name'] = pod.name
|
|
svc.update()
|
|
LOG.info(f"Link master service with {pod.name}")
|
|
|
|
|
|
def is_ready(pod):
|
|
if pod.ready and "deletionTimestamp" not in pod.metadata:
|
|
return True
|
|
|
|
|
|
def main():
|
|
while True:
|
|
for pod in get_mariadb_pods():
|
|
pod.reload()
|
|
if is_ready(pod):
|
|
link_master_service(pod)
|
|
break
|
|
LOG.debug(f"Sleeping for {MARIADB_CONTROLLER_CHECK_PODS_DELAY}")
|
|
time.sleep(MARIADB_CONTROLLER_CHECK_PODS_DELAY)
|
|
|
|
|
|
main()
|