Add and use ansible module for docker-compose

This ansible module for docker-compose allows for idempotency. I have
submitted a pull request upstream to ansible-modules-extra to include
this new module. When/if the module is accepted upstream if can be
removed from the local module library.

The two playbooks have been updated to use this module. The database
data container does not support idempotency due to the fact that it
exists instead of sleeps. Therefore each time `docker-compose up` is
called, it will start the container and register a change. The
message-broker does not have this issue and will remain unchanged even
repeatedly running these playbooks.

Due to the use of a special branch of docker-compose provided by sdake,
this module requires at least docker-compose==1.2.0rc1

Change-Id: If1644eaa3bff0c2a007fa2d479a95bea941945f6
This commit is contained in:
Sam Yaple 2015-03-30 22:19:20 -05:00
parent cf3086ed3b
commit fd5c23ad7a
3 changed files with 312 additions and 2 deletions

View File

@ -0,0 +1,302 @@
#!/usr/bin/python
DOCUMENTATION = '''
---
module: docker_compose
version_added: 1.8.4
short_description: Manage docker containers with docker-compose
description:
- Manage the lifecycle of groups of docker containers with docker-compose
options:
command:
description:
- Select the compose action to perform
required: true
choices: ['build', 'kill', 'pull', 'rm', 'scale', 'start', 'stop', 'restart', 'up']
compose_file:
description:
- Specify the compose file to build from
required: true
type: bool
insecure_registry:
description:
- Allow access to insecure registry (HTTP or TLS with a CA not known by the Docker daemon)
type: bool
kill_signal:
description:
- The SIG to send to the docker container process when killing it
default: SIGKILL
no_build:
description:
- Do not build an image, even if it's missing
type: bool
no_deps:
description:
- Don't start linked services
type: bool
no_recreate:
description:
- If containers already exist, don't recreate them
type: bool
project_name:
description:
- Specify project name (defaults to directory name of the compose file)
type: str
service_names:
description:
- Only modify services in this list (can be used in conjunction with no_deps)
type: list
stop_timeout:
description:
- The amount of time in seconds to wait for an instance to cleanly terminate before killing it (can be used in conjunction with stop_timeout)
default: 10
type: int
author: Sam Yaple
requirements: [ "docker-compose", "docker >= 1.3" ]
'''
EXAMPLES = '''
Compose web application:
- hosts: web
tasks:
- name: compose super important weblog
docker_compose: command="up" compose_file="/opt/compose/weblog.yml"
Compose only mysql server from previous example:
- hosts: web
tasks:
- name: compose mysql
docker_compose: command="up" compose_file="/opt/compose/weblog.yml" service_names=['mysql']
Compose project with specified prefix:
- hosts: web
tasks:
- name: compose weblog named "myproject_weblog_1"
docker_compose: command="up" compose_file="/opt/compose/weblog.yml" project_name="myproject"
Compose project only if already built (or no build instructions). Explicitly refuse to build the container image(s):
- hosts: web
tasks:
- name: compose weblog
docker_compose: command="up" compose_file="/opt/compose/weblog.yml" no_build=True
Allow the container image to be pulled from an insecure registry (this requires the docker daemon to allow the insecure registry as well):
- hosts: web
tasks:
- name: compose weblog from local registry
docker_compose: command="up" compose_file="/opt/compose/weblog.yml" insecure_registry=True
Start the containers in the compose project, but do not create any:
- hosts: web
tasks:
- name: compose weblog
docker_compose: command="start" compose_file="/opt/compose/weblog.yml"
Removed all the containers associated with a project; only wait 5 seconds for the container to respond to a SIGTERM:
- hosts: web
tasks:
- name: Destroy ALL containers for project "devweblog"
docker_compose: command="rm" stop_timeout=5 compose_file="/opt/compose/weblog.yml" project_name="devweblog"
'''
HAS_DOCKER_COMPOSE = True
import re
try:
from compose import config
from compose.cli.command import Command as compose_command
from compose.cli.docker_client import docker_client
except ImportError, e:
HAS_DOCKER_COMPOSE = False
TIMEMAP = {
'second': 0,
'seconds': 0,
'minute': 1,
'minutes': 1,
'hour': 2,
'hours': 2,
'weeks': 3,
'months': 4,
'years': 5,
}
class DockerComposer:
def __init__(self, module):
self.module = module
self.compose_file = self.module.params.get('compose_file')
self.insecure_registry = self.module.params.get('insecure_registry')
self.no_build = self.module.params.get('no_build')
self.no_cache = self.module.params.get('no_cache')
self.no_deps = self.module.params.get('no_deps')
self.no_recreate = self.module.params.get('no_recreate')
self.project_name = self.module.params.get('project_name')
self.stop_timeout = self.module.params.get('stop_timeout')
self.scale = self.module.params.get('scale')
self.service_names = self.module.params.get('service_names')
self.project = compose_command.get_project(compose_command(),
self.compose_file,
self.project_name,
)
self.containers = self.project.client.containers(all=True)
def build(self):
self.project.build(no_cache = self.no_cache,
service_names = self.service_names,
)
def kill(self):
self.project.kill(signal = self.kill_signal,
service_names = self.service_names,
)
def pull(self):
self.project.pull(insecure_registry = self.insecure_registry,
service_names = self.service_names,
)
def rm(self):
self.stop()
self.project.remove_stopped(service_names = self.service_names)
def scale(self):
for s in self.service_names:
try:
num = int(self.scale[s])
except ValueError:
msg = ('Value for scaling service "%s" should be an int, but '
'value "%s" was recieved' % (s, self.scale[s]))
module.fail_json(msg=msg, failed=True)
try:
project.get_service(s).scale(num)
except CannotBeScaledError:
msg = ('Service "%s" cannot be scaled because it specifies a '
'port on the host.' % s)
module.fail_json(msg=msg, failed=True)
def start(self):
self.project.start(service_names = self.service_names)
def stop(self):
self.project.stop(service_names = self.service_names,
timeout = self.stop_timeout,
)
def restart(self):
self.project.restart(service_names = self.service_names)
def up(self):
self.project_contains = self.project.up(
detach = True,
do_build = not self.no_build,
insecure_registry = self.insecure_registry,
recreate = not self.no_recreate,
service_names = self.service_names,
start_deps = not self.no_deps,
)
def check_if_changed(self):
new_containers = self.project.client.containers(all=True)
for pc in self.project_contains:
old_container = None
new_container = None
name = '/' + re.split(' |>',str(pc))[1]
for c in self.containers:
if c['Names'][0] == name:
old_container = c
for c in new_containers:
if c['Names'][0] == name:
new_container = c
if not old_container or not new_container:
return True
if old_container['Created'] != new_container['Created']:
return True
old_status = re.split(' ', old_container['Status'])
new_status = re.split(' ', new_container['Status'])
if old_status[0] != new_status[0]:
return True
if old_status[0] == 'Up':
if TIMEMAP[old_status[-1]] > TIMEMAP[new_status[-1]]:
return True
else:
if TIMEMAP[old_status[-2]] < TIMEMAP[new_status[-2]]:
return True
return False
def check_dependencies(module):
if not HAS_DOCKER_COMPOSE:
msg = ('`docker-compose` does not seem to be installed, but is required '
'by the Ansible docker-compose module.')
module.fail_json(failed=True, msg=msg)
def main():
module = AnsibleModule(
argument_spec = dict(
command = dict(required=True,
choices=['build', 'kill', 'pull', 'rm',
'scale', 'start', 'stop',
'restart', 'up']
),
compose_file = dict(required=True, type='str'),
insecure_registry = dict(type='bool'),
kill_signal = dict(default='SIGKILL'),
no_build = dict(type='bool'),
no_cache = dict(type='bool'),
no_deps = dict(type='bool'),
no_recreate = dict(type='bool'),
project_name = dict(type='str'),
scale = dict(type='dict'),
service_names = dict(type='list'),
stop_timeout = dict(default=10, type='int')
)
)
check_dependencies(module)
try:
composer = DockerComposer(module)
command = getattr(composer, module.params.get('command'))
command()
changed = composer.check_if_changed()
module.exit_json(changed=changed)
except Exception, e:
try:
changed = composer.check_if_changed()
except Exception:
changed = True
module.exit_json(failed=True, changed=changed, msg=repr(e))
# import module snippets
from ansible.module_utils.basic import *
if __name__ == '__main__':
main()

View File

@ -1,3 +1,7 @@
---
- name: Bringing up mariadb service(s)
command: docker-compose -f /root/kolla/compose/mariadb.yml up -d
docker_compose:
project_name: mariadb
compose_file: /usr/share/kolla/compose/mariadb.yml
command: up
no_recreate: true

View File

@ -1,3 +1,7 @@
---
- name: Bringing up rabbitmq service(s)
command: docker-compose -f /root/kolla/compose/rabbitmq.yml up -d
docker_compose:
project_name: rabbitmq
compose_file: /usr/share/kolla/compose/rabbitmq.yml
command: up
no_recreate: true