openstack/sunbeam-charms
Code Issues Proposed changes

Add support for healthchecks

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Add healthchecks for WSGI, OVN services
Check healthcheck in update-status

Change-Id: I3df7026f18cdf5ad897f4dcf1d06a3c3f6fd80c4
This commit is contained in:
Hemanth Nakkina 2022-08-25 09:51:04 +05:30
parent c0a56f4928
commit cdf186793d
4 changed files with 149 additions and 1 deletions
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27
ops-sunbeam/ops_sunbeam/charm.py
View File

@ -66,6 +66,8 @@ class OSBaseOperatorCharm(ops.charm.CharmBase):
self.relation_handlers = self.get_relation_handlers()
self.pebble_handlers = self.get_pebble_handlers()
self.framework.observe(self.on.config_changed, self._on_config_changed)
# TODO: change update_status based on compound_status feature
self.framework.observe(self.on.update_status, self._on_update_status)
def can_add_handler(
self,
@ -235,6 +237,10 @@ class OSBaseOperatorCharm(ops.charm.CharmBase):
if self.unit.is_leader() and self.supports_peer_relation:
self.set_leader_ready()
# Add healthchecks to the plan
for ph in self.pebble_handlers:
ph.add_healthchecks()
self.unit.status = ops.model.ActiveStatus()
self._state.bootstrapped = True
@ -395,6 +401,22 @@ class OSBaseOperatorCharm(ops.charm.CharmBase):
self._state.bootstrapped = False
return
def _on_update_status(self, event: ops.framework.EventBase) -> None:
"""Update status event handler."""
status = []
for ph in self.pebble_handlers:
ph.assess_status()
# Below lines are not required with compound status feature
if ph.status:
status.append(ph.status)
# Need to be changed once compound status in place
if len(status) == 0:
self.unit.status = ops.model.ActiveStatus()
else:
status_msg = ','.join(status)
self.unit.status = ops.model.BlockedStatus(status_msg)
class OSBaseOperatorAPICharm(OSBaseOperatorCharm):
"""Base class for OpenStack API operators."""
@ -623,3 +645,8 @@ class OSBaseOperatorAPICharm(OSBaseOperatorCharm):
def db_sync_container_name(self) -> str:
"""Name of Containerto run db sync from."""
return self.wsgi_container_name
@property
def healthcheck_http_url(self) -> str:
"""Healthcheck HTTP URL for the service."""
return f'http://localhost:{self.default_public_ingress_port}/'

89
ops-sunbeam/ops_sunbeam/container_handlers.py
View File

@ -66,6 +66,9 @@ class PebbleHandler(ops.charm.Object):
self.openstack_release = openstack_release
self.callback_f = callback_f
self.setup_pebble_handler()
# The structure of status variable and corresponding logic
# will change with compund status feature
self.status = ""
def setup_pebble_handler(self) -> None:
"""Configure handler for pebble ready event."""
@ -111,6 +114,10 @@ class PebbleHandler(ops.charm.Object):
"""Pebble configuration layer for the container."""
return {}
def get_healthcheck_layer(self) -> dict:
"""Pebble configuration for health check layer for the container."""
return {}
@property
def directories(self) -> List[ContainerDir]:
"""List of directories to create in container."""
@ -194,6 +201,61 @@ class PebbleHandler(ops.charm.Object):
if exception_on_error:
raise
def add_healthchecks(self) -> None:
"""Add healthcheck layer to the plan."""
healthcheck_layer = self.get_healthcheck_layer()
if not healthcheck_layer:
logger.debug("Healthcheck layer not defined in pebble handler")
return
container = self.charm.unit.get_container(self.container_name)
try:
plan = container.get_plan()
if not plan.checks:
logger.debug("Adding healthcheck layer to the plan")
container.add_layer(
"healthchecks", healthcheck_layer, combine=True)
except ops.pebble.ConnectionError as connect_error:
logger.error("Not able to add Healthcheck layer")
logger.exception(connect_error)
def assess_status(self) -> str:
"""Assess Healthcheck status.
:return: status message based on healthchecks
:rtype: str
"""
failed_checks = []
container = self.charm.unit.get_container(self.container_name)
try:
checks = container.get_checks(level=ops.pebble.CheckLevel.READY)
for name, check in checks.items():
if check.status != ops.pebble.CheckStatus.UP:
failed_checks.append(name)
# Verify alive checks if ready checks are missing
if not checks:
checks = container.get_checks(
level=ops.pebble.CheckLevel.ALIVE)
for name, check in checks.items():
if check.status != ops.pebble.CheckStatus.UP:
failed_checks.append(name)
except ops.model.ModelError:
logger.warning(
f'Health check online for {self.container_name} not defined')
except ops.pebble.ConnectionError as connect_error:
logger.exception(connect_error)
failed_checks.append("Pebble Connection Error")
if failed_checks:
self.status = (
f'Health check failed for {self.container_name}: '
f'{failed_checks}'
)
else:
self.status = ''
class ServicePebbleHandler(PebbleHandler):
"""Container handler for containers which manage a service."""
@ -295,6 +357,33 @@ class WSGIPebbleHandler(PebbleHandler):
},
}
def get_healthcheck_layer(self) -> dict:
"""Apache WSGI health check pebble layer.
:returns: pebble health check layer configuration for wsgi service
"""
return {
"checks": {
"up": {
"override": "replace",
"level": "alive",
"period": "10s",
"timeout": "3s",
"threshold": 3,
"exec": {
"command": "service apache2 status"
}
},
"online": {
"override": "replace",
"level": "ready",
"http": {
"url": self.charm.healthcheck_http_url
}
},
}
}
def init_service(self, context: sunbeam_core.OPSCharmContexts) -> None:
"""Enable and start WSGI service."""
container = self.charm.unit.get_container(self.container_name)

29
ops-sunbeam/ops_sunbeam/ovn/container_handlers.py
View File

@ -28,6 +28,11 @@ class OVNPebbleHandler(sunbeam_chandlers.ServicePebbleHandler):
"""Path to OVN service wrapper."""
raise NotImplementedError
@property
def status_command(self) -> str:
"""Command to check status of service."""
raise NotImplementedError
def init_service(self, context: sunbeam_core.OPSCharmContexts) -> None:
"""Initialise service ready for use.
@ -46,7 +51,11 @@ class OVNPebbleHandler(sunbeam_chandlers.ServicePebbleHandler):
raise NotImplementedError
def get_layer(self) -> dict:
"""Pebble configuration layer for OVN service."""
"""Pebble configuration layer for OVN service.
:returns: pebble layer configuration for service
:rtype: dict
"""
return {
"summary": f"{self.service_description} service",
"description": ("Pebble config layer for "
@ -61,6 +70,24 @@ class OVNPebbleHandler(sunbeam_chandlers.ServicePebbleHandler):
},
}
def get_healthcheck_layer(self) -> dict:
"""Health check pebble layer.
:returns: pebble health check layer configuration for OVN service
:rtype: dict
"""
return {
"checks": {
"online": {
"override": "replace",
"level": "ready",
"exec": {
"command": f"{self.status_command}"
}
},
}
}
@property
def directories(self) -> List[sunbeam_chandlers.ContainerDir]:
"""Directories to creete in container."""

5
ops-sunbeam/unit_tests/test_charms.py
View File

@ -250,3 +250,8 @@ class MyAPICharm(sunbeam_charm.OSBaseOperatorAPICharm):
def template_dir(self) -> str:
"""Templates dir."""
return self._template_dir
@property
def healthcheck_http_url(self) -> str:
"""Healthcheck HTTP URL for the service."""
return f'http://localhost:{self.default_public_ingress_port}/v3'