ansible使用5-Variables

ansible使用5-Variables

变量命名

支持数字、字母、下划线

有效：foo_port, foo5 无效：foo-port, foo port, foo.port, 12

playbook定义

- hosts: webservers vars: http_port: 80

jinja2模板使用变量

My amp goes to {{ max_amp_value }} template: src=foo.cfg.j2 dest={{ remote_install_path }}/foo.cfg

Jinja2 Filters

格式化数据

{{ some_variable | to_nice_json }} {{ some_variable | to_nice_yaml }}

使用条件表达式

tasks: - shell: /usr/bin/foo register: result ignore_errors: True - debug: msg="it failed" when: result|failed # in most cases you'll want a handler, but if you want to do something right now, this is nice - debug: msg="it changed" when: result|changed - debug: msg="it succeeded" when: result|success - debug: msg="it was skipped" when: result|skipped

强制变量定义

{{ variable | mandatory }}

变量默认值

{{ some_variable | default(5) }}

变量省略值

- name: touch files with an optional mode file: dest={{item.path}} state=touch mode={{item.mode|default(omit)}} with_items: - path: /tmp/foo - path: /tmp/bar - path: /tmp/baz mode: "0444"

列表

# 最小值 {{ list1 | min }} # 最大值 {{ [3, 4, 2] | max }} # 唯一值 {{ list1 | unique }} # 并集 {{ list1 | union(list2) }} # 交集 {{ list1 | intersect(list2) }} # 补集（存在list1,不存在list2） {{ list1 | difference(list2) }} # 对称差集 (不同时存在每个列表) {{ list1 | symmetric_difference(list2) }}

版本比较

{{ ansible_distribution_version | version_compare('12.04', '>=') }} # <, lt, <=, le, >, gt, >=, ge, ==, =, eq, !=, <>, ne # 版本分析strict=True，默认值false

随机数

{{ ['a','b','c']|random }} => 'c' {{ 59 |random}} * * * * root /script/from/cron {{ 100 |random(step=10) }} => 70 {{ 100 |random(1, 10) }} => 31 {{ 100 |random(start=1, step=10) }} => 51

洗牌(shuffle)

{{ ['a','b','c']|shuffle }} => ['c','a','b'] {{ ['a','b','c']|shuffle }} => ['b','c','a']

其他

# 列表转字符串 {{ list | join(" ") }} # 文件全路径 {{ path | basename }} # 目录全路径 {{ path | dirname }} # 用户目录（～）全路径 {{ path | expanduser }} #　link的路径 {{ path | readlink }} #　Base64加解密 {{ encoded | b64decode }} {{ decoded | b64encode }} # 文件的sha1sum {{ filename | sha1 }}

bool

- debug: msg=test when: some_string_value | bool

正则

vars: url: "http://example.com/users/foo/resources/bar" tasks: - shell: "msg='matched pattern 1'" when: url | match("http://example.com/users/.*/resources/.*") - debug: "msg='matched pattern 2'" when: url | search("/users/.*/resources/.*") # convert "ansible" to "able" {{ 'ansible' | regex_replace('^a.*i(.*)$', 'a\\1') }} # convert "foobar" to "bar" {{ 'foobar' | regex_replace('^f.*o(.*)$', '\\1') }} - hosts: app_servers vars: app_path: "{{ base_path }}/22"

Facts

'''bash ansible hostname -m setup

{{ ansible_devices.sda.model }} {{ ansible_hostname }} '''

Turning Off Facts

- hosts: whatever gather_facts: no

本地facts(自定义facts)

# /etc/ansible/facts.d/preferences.fact [general] asdf=1 bar=2 # 命令 ansible <hostname> -m setup -a "filter=ansible_local" # API "ansible_local": { "preferences": { "general": { "asdf" : "1", "bar" : "2" } } } # 引用 {{ ansible_local.preferences.general.asdf }} # 部署 - hosts: webservers tasks: - name: create directory for ansible custom facts file: state=directory recurse=yes path=/etc/ansible/facts.d - name: install custom impi fact copy: src=ipmi.fact dest=/etc/ansible/facts.d - name: re-read facts after adding custom fact setup: filter=ansible_local

Fact Caching

{{ hostvars['asdf.example.com']['ansible_os_family'] }} # /etc/ansible/ansible.cfg [defaults] fact_caching = redis fact_caching_timeout = 86400 # seconds yum install redis service redis start pip install redis

Registered Variables

- hosts: web_servers tasks: - shell: /usr/bin/foo register: foo_result ignore_errors: True - shell: /usr/bin/bar when: foo_result.rc == 5

Accessing Complex Variable Data

{{ ansible_eth0["ipv4"]["address"] }} {{ ansible_eth0.ipv4.address }} {{ foo[0] }}

Magic Variables, and How To Access Information About Other Hosts

{{ hostvars['test.example.com']['ansible_distribution'] }} {% if 'webserver' in group_names %} # some part of a configuration file that only applies to webservers {% endif %} {% for host in groups['app_servers'] %} # something that applies to all app servers. {% endfor %} # example {% for host in groups['app_servers'] %} {{ hostvars[host]['ansible_eth0']['ipv4']['address'] }} {% endfor %}

Variable File Separation

--- - hosts: all remote_user: root vars: favcolor: blue vars_files: - /vars/external_vars.yml tasks: - name: this is just a placeholder command: /bin/echo foo --- # in the above example, this would be vars/external_vars.yml somevar: somevalue password: magic

Passing Variables On The Command Line

ansible-playbook release.yml --extra-vars "version=1.23.45 other_variable=foo" #example --- - hosts: '{{ hosts }}' remote_user: '{{ user }}' tasks: - ... ansible-playbook release.yml --extra-vars "hosts=vipers user=starbuck" or --extra-vars '{"pacman":"mrs","ghosts":["inky","pinky","clyde","sue"]}' or --extra-vars "@some_file.json"

Variable Precedence: Where Should I Put A Variable?

#组变量默认值在group_vars/all --- # file: /etc/ansible/group_vars/all # this is the site wide default ntp_server: default-time.example.com # 组变量，覆盖组默认变量 --- # file: /etc/ansible/group_vars/boston ntp_server: boston-time.example.com # 主机变量，覆盖组变量 --- # file: /etc/ansible/host_vars/xyz.boston.example.com ntp_server: override.example.com

role variable precedence

--- # file: roles/x/defaults/main.yml # if not overridden in inventory or as a parameter, this is the value that will be used http_port: 80 # 不能覆盖默认值 --- # file: roles/x/vars/main.yml # this will absolutely be used in this role http_port: 80 # 使用这种方式覆盖默认值 roles: - { name: apache, http_port: 8080 } roles: - { role: app_user, name: Ian } - { role: app_user, name: Terry } - { role: app_user, name: Graham } - { role: app_user, name: John } # roles/common/vars/main.yml roles: - { role: common_settings } - { role: something, foo: 12 } - { role: something_else } posted on 2015-01-04 11:27 北京涛子 阅读( ...) 评论( ...) 编辑 收藏

转载于:https://www.cnblogs.com/liujitao79/p/4200646.html