如何设置 register 变量以在 ansible 的播放之间保持不变? [英] How do I set register a variable to persist between plays in ansible?
问题描述
我有一个 ansible playbook，我希望我在一台机器上注册的变量在另一台机器上可用.
I have an ansible playbook, where I'd like a variable I register on one machine to be available on another.
就我而言，我想在 localhost 上运行一个命令，在这种情况下是 git rev-parse --abbrev-ref HEAD，这样我就可以记录当前 git 分支和 sha1，并注册此输出，以便我稍后在第二个游戏中在 main 组中的任何机器上工作时参考它.
In my case, I'd like to run a command on localhost, in this case git rev-parse --abbrev-ref HEAD, so I can make a note of the current git branch, and sha1, and register this output, so I can refer to it later when working any machine in the main group, in the second play.
但是，我不清楚如何在 localhost 上注册变量，因此我可以从 main 访问它.当我尝试在第二场比赛中访问该变量时，我收到以下消息:
However, it's not clear to me how I register a variable on localhost, so I can access it from main. When I try to access the variable in the second play I get this message:
TASK: [debug msg={{ app_git_sha1.stdout }}] ***********************************
fatal: [main] => One or more undefined variables: 'app_git_sha1' is undefined
这是我正在使用的游戏.有什么明显的我应该做的吗?
Here's the play I'm using. Is there anything obvious I should be doing?
---
- hosts: localhost
connection: local
gather_facts: no
tasks:
- name: register current branch
command: git rev-parse --abbrev-ref HEAD
register: git_branch
sudo: no
when: vagrant
tags:
- debugsha
- debug: msg={{ git_branch.stdout }}
tags:
- debugsha
- name: register the SHA1 of the branch being deployed
command: git rev-parse origin/{{ git_branch.stdout }}
register: app_git_sha1
sudo: no
tags:
- slack
- debugsha
- debug: msg={{ app_git_sha1.stdout }}
tags:
- debugsha
- hosts: main
sudo: yes
roles:
- role: productscience.deploy_user
# TODO reprovision using these roles, for consistency
# - role: app.essentials
# - role: zenoamaro.postgresql
- role: productscience.papertrailapp
- role: jdauphant.nginx
tasks:
- include: setup.yml
# - include: db.yml
- name: checkout source control when deploying to remote servers
include: source.yml
when: not vagrant
tags:
- deploy
- include: django.yml
tags:
- deploy
- name: include vagrant specific dependencies for local development
include: vagrant.yml
when: vagrant
handlers:
- name: restart postgres
sudo: yes
service: name=postgresql state=restarted
- name: start restart uwsgi
sudo: yes
service: name={{ app }} state=restarted
- hosts: localhost
connection: local
gather_facts: no
tasks:
- name: register the SHA1 of the branch being deployed
when: not vagrant
command: git rev-parse origin/{{ git_branch }}
register: git_sha
tags:
- slack
- name: Send notification message via Slack all options
when: not vagrant
tags:
- slack
local_action:
module: slack
token: "{{ wof_slack_token }}"
msg: "Deployment of `{{ git_branch }}` to {{ app_url }} completed with sha `{{ git_sha.stdout }}`"
channel: "#wof"
username: "Ansible deploy-o-tron"
推荐答案
您遇到的问题是您试图从另一台主机的事实/变量中引用一个主机的事实/变量.您需要记住，在 Ansible 中，分配给主机 localhost 的变量 app_git_sha1 不同于分配给主机 app_git_sha1 的变量 app_git_sha1code>main 或任何其他主机.如果您想从另一台主机访问一个主机的事实/变量，那么您需要通过 hostvars 变量显式引用它.关于这个在这个问题.
The problem you're running into is that you're trying to reference facts/variables of one host from those of another host. You need to keep in mind that in Ansible, the variable app_git_sha1 assigned to the host localhost is distinct from the variable app_git_sha1 assigned to the host main or any other host. If you want to access one hosts facts/variables from another host then you need to explicitly reference it via the hostvars variable. There's a bit more of a discussion on this in this question.
假设你有一个这样的剧本:
Suppose you have a playbook like this:
- hosts: localhost
tasks:
- command: /bin/echo "this is a test"
register: foo
- hosts: localhost
tasks:
- debug: var=foo
这将起作用，因为您在两个播放中都引用了主机 localhost 和 localhosts 变量 foo 的实例.这个剧本的输出是这样的:
This will work because you're referencing the host localhost and localhosts's instance of the variable foo in both plays. The output of this playbook is something like this:
PLAY [localhost] **************************************************************
GATHERING FACTS ***************************************************************
ok: [localhost]
TASK: [command /bin/echo "this is a test"] ************************************
changed: [localhost]
PLAY [localhost] **************************************************************
GATHERING FACTS ***************************************************************
ok: [localhost]
TASK: [debug var=foo] *********************************************************
ok: [localhost] => {
"var": {
"foo": {
"changed": true,
"cmd": [
"/bin/echo",
"this is a test"
],
"delta": "0:00:00.004585",
"end": "2015-11-24 20:49:27.462609",
"invocation": {
"module_args": "/bin/echo \"this is a test\"",
"module_complex_args": {},
"module_name": "command"
},
"rc": 0,
"start": "2015-11-24 20:49:27.458024",
"stderr": "",
"stdout": "this is a test",
"stdout_lines": [
"this is a test"
],
"warnings": []
}
}
}
如果您稍微修改此剧本以在一台主机上运行第一次播放，而在另一台主机上运行第二次播放，您将遇到遇到的错误.解决方案是使用 Ansible 的内置 hostvars 变量让第二个主机显式引用第一个 hosts 变量.所以像这样修改第一个例子:
If you modify this playbook slightly to run the first play on one host and the second play on a different host, you'll get the error that you encountered. The solution is to use Ansible's built-in hostvars variable to have the second host explicitly reference the first hosts variable. So modify the first example like this:
- hosts: localhost
tasks:
- command: /bin/echo "this is a test"
register: foo
- hosts: anotherhost
tasks:
- debug: var=foo
when: foo is defined
- debug: var=hostvars['localhost']['foo']
when: hostvars['localhost']['foo'] is defined
这个剧本的输出显示第一个任务被跳过，因为 foo 不是由主机 anotherhost 定义的.但是第二个任务成功了，因为它显式引用了 localhosts 变量的实例 foo:
The output of this playbook shows that the first task is skipped because foo is not defined by the host anotherhost. But the second task succeeds because it's explicitly referencing localhosts's instance of the variable foo:
TASK: [debug var=foo] *********************************************************
skipping: [anotherhost]
TASK: [debug var=hostvars['localhost']['foo']] **************************
ok: ['anotherhost'] => {
"var": {
"hostvars['localhost']['foo']": {
"changed": true,
"cmd": [
"/bin/echo",
"this is a test"
],
"delta": "0:00:00.005950",
"end": "2015-11-24 20:54:04.319147",
"invocation": {
"module_args": "/bin/echo \"this is a test\"",
"module_complex_args": {},
"module_name": "command"
},
"rc": 0,
"start": "2015-11-24 20:54:04.313197",
"stderr": "",
"stdout": "this is a test",
"stdout_lines": [
"this is a test"
],
"warnings": []
}
}
}
所以，简而言之，您希望修改 main 剧本中的变量引用，以这种方式引用 localhost 变量:
So, in a nutshell, you want to modify the variable references in your main playbook to reference the localhost variables in this manner:
{{ hostvars['localhost']['app_git_sha1'] }}
这篇关于如何设置 register 变量以在 ansible 的播放之间保持不变?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
