"""Functions that update system services."""
import subprocess
import docker
from . import log
from .config import ClientConfig
from .config.service import (
DockerContainer,
DockerService,
RCService,
Script,
SystemdUnit,
)
from .errors import (
DockerContainerError,
DockerContainerNotFound,
DockerServiceError,
DockerServiceNotFound,
RCServiceError,
ScriptError,
SystemdError,
UpdateError,
)
[docs]
def update_docker_container(spec: DockerContainer, client_config: ClientConfig):
"""Update a docker container.
Arguments:
spec: The update service specifications.
client_config: The CertDeploy client config.
Raises:
DockerContainerError: When there is a docker error while restarting the
container.
DockerContainerNotFound: When the specified container cannot be found.
"""
log.debug('Updating %s', spec)
api = docker.DockerClient(base_url=client_config.docker_url)
matches = api.containers.list(filters=spec.filters)
if not matches:
err = DockerContainerNotFound(spec)
if client_config.fail_fast:
raise err
log.error(err)
return
for container in matches:
try:
container.restart(timeout=spec.timeout)
except docker.errors.APIError as err:
error = DockerContainerError(
spec,
err,
str(container.attrs.get('Names')),
)
if client_config.fail_fast:
raise error from err
log.error(error, exc_info=err)
else:
log.info(
'Docker container updated: names=%s, filters=%s',
container.attrs.get('Names'),
spec.filters,
)
[docs]
def update_docker_service(spec: DockerService, client_config: ClientConfig):
"""Force update a docker service.
Arguments:
spec: The update service specifications.
client_config: The CertDeploy client config.
Raises:
DockerServiceError: When there is a docker error while force updating
the service.
DockerServiceNotFound: When the specified service cannot be found.
"""
log.debug('Updating %s', spec)
api = docker.DockerClient(base_url=client_config.docker_url)
if spec.name:
try:
matches = [api.services.get(spec.name)]
except docker.errors.NotFound:
matches = []
else:
matches = api.services.list(filters=spec.filters)
if not matches:
# Borrowing the formatting from the exception
err = DockerServiceNotFound(spec)
if client_config.fail_fast:
raise err
log.error(err)
return
for service in matches:
try:
warnings = service.force_update()
except docker.errors.APIError as err:
# Borrowing the formatting from the exception
error = DockerServiceError(spec, service_name=service.name)
if client_config.fail_fast:
raise error from err
log.error(error, exc_info=err)
else:
for warn in warnings.get('Warnings') or []:
log.warning('Got warning from the Docker API: %s', warn)
log.info('Docker service updated: name=%s', service.name)
[docs]
def update_rc_service(spec: RCService, client_config: ClientConfig):
"""Update an init system service.
Arguments:
spec: The update service specifications.
client_config: The CertDeploy client config.
Raises:
RCServiceError: When the `service` encounters an `OSError`, doesn't
finish in a timely manner (according to `script.timeout`), or exits
non-zero.
"""
log.debug('Updating %s', spec)
cmd = [client_config.rc_service_exec, spec.name, spec.action]
try:
proc = subprocess.Popen(
cmd,
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
)
proc.wait(timeout=spec.timeout)
except (OSError, subprocess.TimeoutExpired) as err:
# Regular errors from the `service` call shouldn't halt the whole
# set of updates unless fail_fast is True.
# Borrowing the exception's formatting.
error = RCServiceError(spec, err)
if client_config.fail_fast:
raise error from err
log.error(error, exc_info=err)
return
stdout = proc.stdout.read().decode()
log.debug(
'RC service command %s returned=%s. Got combined '
'stdout/stderr: \n%s', # nofmt
proc.returncode,
cmd,
stdout,
)
if proc.returncode != 0:
# Borrowing the exception's formatting.
err = RCServiceError(spec, stdout=stdout)
if client_config.fail_fast:
raise err
log.error(err)
log.info('RC service %s %sed.', spec.name, spec.action)
[docs]
def update_script(script: Script, client_config: ClientConfig):
"""Update the system with a script.
Arguments:
script: The update service specifications.
client_config: The CertDeploy client config.
Raises:
ScriptError: When the script encounters an `OSError`, doesn't finish in
a timely manner (according to `script.timeout`), or exits non-zero.
"""
log.debug('Updating %s', script)
try:
proc = subprocess.Popen(
[script.script_path],
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
)
proc.wait(timeout=script.timeout)
except (OSError, subprocess.TimeoutExpired) as err:
# Regular errors from the script shouldn't halt the whole
# set of updates unless fail_fast is True.
# Borrowing the exception's formatting.
error = ScriptError(script, err)
if client_config.fail_fast:
raise error from err
log.error(error, exc_info=err)
return
stdout = proc.stdout.read().decode()
log.debug(
'Script %s returned=%s, combined stdout/stderr: \n%s',
script.script_path,
proc.returncode,
stdout,
)
if proc.returncode != 0:
# Borrowing the exception's formatting
err = ScriptError(script, proc=proc, stdout=stdout)
if client_config.fail_fast:
raise err
log.error(err)
else:
log.info('Script %s returned=%s', script.script_path, proc.returncode)
[docs]
def update_systemd_unit(unit: SystemdUnit, client_config: ClientConfig):
"""Update a Systemd unit.
Arguments:
unit: The update service specifications.
client_config: The CertDeploy client config.
Raises:
SystemdError: When the systemctl encounters an `OSError`, doesn't
finish in a timely manner (according to `script.timeout`), or exits
non-zero.
"""
log.debug('Updating %s', unit)
cmd = [client_config.systemd_exec, unit.action, unit.name]
try:
proc = subprocess.Popen(
cmd,
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
)
proc.wait(timeout=unit.timeout)
except (OSError, subprocess.TimeoutExpired) as err:
# Regular errors from the systemctl call shouldn't halt the whole
# set of updates unless fail_fast is True.
# Borrowing the exception's formatting.
error = SystemdError(unit, err)
if client_config.fail_fast:
raise error from err
log.error(error, exc_info=err)
return
stdout = proc.stdout.read().decode()
log.debug(
'Systemctl command %s returned=%s. Got combined ' 'stdout/stderr: \n%s',
proc.returncode,
cmd,
stdout,
)
if proc.returncode != 0:
# Borrowing the exception's formatting.
err = SystemdError(unit, stdout=stdout)
if client_config.fail_fast:
raise err
log.error(err)
log.info('Systemd unit %s %sed.', unit.name, unit.action)
# An index of Service types to update functions
_UPDATER_MAP = {
DockerContainer: update_docker_container,
DockerService: update_docker_service,
RCService: update_rc_service,
Script: update_script,
SystemdUnit: update_systemd_unit,
}
[docs]
def update_services(config: ClientConfig):
"""Update all services in `config.services`.
Arguments:
config: The CertDeploy client config.
"""
for service in config.services:
try:
_UPDATER_MAP[type(service)](service, config)
except UpdateError as err:
# Don't halt on UpdateError unless fail_fast is True
# ConfigError and any unexpected errors should halt
if config.fail_fast:
raise err from err