saya menciptakan skrip untuk menerapkan image Docker yang diperbarui ke layanan staging di ECS, sehingga definisi tugas yang sesuai mengacu pada versi image Docker saat ini. Saya tidak tahu pasti apakah saya mengikuti praktik terbaik, jadi masukan akan kami terima.
Agar skrip berfungsi, Anda memerlukan instans ECS cadangan atau file deploymentConfiguration.minimumHealthyPercent nilai sehingga ECS dapat mencuri instans untuk menerapkan definisi tugas yang diperbarui.
Algoritme saya seperti ini:
- Beri tag pada gambar Docker yang sesuai dengan container dalam definisi tugas dengan revisi Git.
- Dorong tag gambar Docker ke registri yang sesuai.
- Batalkan pendaftaran definisi tugas lama dalam keluarga definisi tugas.
- Daftarkan definisi tugas baru, sekarang mengacu pada gambar Docker yang ditandai dengan revisi Git saat ini.
- Perbarui layanan untuk menggunakan definisi tugas baru.
Kode saya ditempel di bawah ini:
deploy-ecs
#!/usr/bin/env python3
import subprocess
import sys
import os.path
import json
import re
import argparse
import tempfile
_root_dir = os.path.abspath(os.path.normpath(os.path.dirname(__file__)))
sys.path.insert(0, _root_dir)
from _common import *
def _run_ecs_command(args):
run_command(['aws', 'ecs', ] + args)
def _get_ecs_output(args):
return json.loads(run_command(['aws', 'ecs', ] + args, return_stdout=True))
def _tag_image(tag, qualified_image_name, purge):
log_info('Tagging image \'{}\' as \'{}\'...'.format(
qualified_image_name, tag))
log_info('Pulling image from registry in order to tag...')
run_command(
['docker', 'pull', qualified_image_name], capture_stdout=False)
run_command(['docker', 'tag', '-f', qualified_image_name, '{}:{}'.format(
qualified_image_name, tag), ])
log_info('Pushing image tag to registry...')
run_command(['docker', 'push', '{}:{}'.format(
qualified_image_name, tag), ], capture_stdout=False)
if purge:
log_info('Deleting pulled image...')
run_command(
['docker', 'rmi', '{}:latest'.format(qualified_image_name), ])
run_command(
['docker', 'rmi', '{}:{}'.format(qualified_image_name, tag), ])
def _register_task_definition(task_definition_fpath, purge):
with open(task_definition_fpath, 'rt') as f:
task_definition = json.loads(f.read())
task_family = task_definition['family']
tag = run_command([
'git', 'rev-parse', '--short', 'HEAD', ], return_stdout=True).strip()
for container_def in task_definition['containerDefinitions']:
image_name = container_def['image']
_tag_image(tag, image_name, purge)
container_def['image'] = '{}:{}'.format(image_name, tag)
log_info('Finding existing task definitions of family \'{}\'...'.format(
task_family
))
existing_task_definitions = _get_ecs_output(['list-task-definitions', ])[
'taskDefinitionArns']
for existing_task_definition in [
td for td in existing_task_definitions if re.match(
r'arn:aws:ecs+:[^:]+:[^:]+:task-definition/{}:\d+'.format(
task_family),
td)]:
log_info('Deregistering task definition \'{}\'...'.format(
existing_task_definition))
_run_ecs_command([
'deregister-task-definition', '--task-definition',
existing_task_definition, ])
with tempfile.NamedTemporaryFile(mode='wt', suffix='.json') as f:
task_def_str = json.dumps(task_definition)
f.write(task_def_str)
f.flush()
log_info('Registering task definition...')
result = _get_ecs_output([
'register-task-definition',
'--cli-input-json', 'file://{}'.format(f.name),
])
return '{}:{}'.format(task_family, result['taskDefinition']['revision'])
def _update_service(service_fpath, task_def_name):
with open(service_fpath, 'rt') as f:
service_config = json.loads(f.read())
services = _get_ecs_output(['list-services', ])[
'serviceArns']
for service in [s for s in services if re.match(
r'arn:aws:ecs:[^:]+:[^:]+:service/{}'.format(
service_config['serviceName']),
s
)]:
log_info('Updating service with new task definition...')
_run_ecs_command([
'update-service', '--service', service,
'--task-definition', task_def_name,
])
parser = argparse.ArgumentParser(
description="""Deploy latest Docker image to staging server.
The task definition file is used as the task definition, whereas
the service file is used to configure the service.
""")
parser.add_argument(
'task_definition_file', help='Your task definition JSON file')
parser.add_argument('service_file', help='Your service JSON file')
parser.add_argument(
'--purge_image', action='store_true', default=False,
help='Purge Docker image after tagging?')
args = parser.parse_args()
task_definition_file = os.path.abspath(args.task_definition_file)
service_file = os.path.abspath(args.service_file)
os.chdir(_root_dir)
task_def_name = _register_task_definition(
task_definition_file, args.purge_image)
_update_service(service_file, task_def_name)
_common.py
import sys
import subprocess
__all__ = ['log_info', 'handle_error', 'run_command', ]
def log_info(msg):
sys.stdout.write('* {}\n'.format(msg))
sys.stdout.flush()
def handle_error(msg):
sys.stderr.write('* {}\n'.format(msg))
sys.exit(1)
def run_command(
command, ignore_error=False, return_stdout=False, capture_stdout=True):
if not isinstance(command, (list, tuple)):
command = [command, ]
command_str = ' '.join(command)
log_info('Running command {}'.format(command_str))
try:
if capture_stdout:
stdout = subprocess.check_output(command)
else:
subprocess.check_call(command)
stdout = None
except subprocess.CalledProcessError as err:
if not ignore_error:
handle_error('Command failed: {}'.format(err))
else:
return stdout.decode() if return_stdout else None