list - Ansible - 根据另一个列表的值从一个列表中获取一个项目

Question

我有一个像这样的站点信息列表:

sites:
  - {host: host1, path: path1, db: db1 }
  - {host: host2, path: path2, db: db2 }
  - {host: host3, path: path3, db: db3 }

和列表中的数据库信息如下:

mysql_databases:
 - { name: db1, encoding: utf8mb4, collation: utf8mb4_unicode_ci }
 - { name: db2, encoding: utf8mb4, collation: utf8mb4_unicode_ci }
 - { name: db3, encoding: utf8mb4, collation: utf8mb4_unicode_ci }

mysql_users:
  - { name: db1, host: "%", password: pass1, priv: "db1.*:ALL", db: db1 }
  - { name: db2, host: "%", password: pass2, priv: "db2.*:ALL", db: db2 }
  - { name: db3, host: "%", password: pass3, priv: "db3.*:ALL", db: db3 }

我有一个使用上述信息创建凭据文件的角色。像这样的东西:

- name: Create file
  template:
    src: "credentials.conf.j2"
    dest: "{{ item.path}}/{{ item.name }}.conf"
  with_items: "{{ sites }}"

有没有什么方法可以在遍历 sites 时向模板发送所有三个列表中的相应信息？列表？

为了便于使用 geerlingguy 的 mysql 角色，这些列表的结构是这样的。

Answer 1

一种系统的方法是将 mysql_* 列表转换为字典。例如

- set_fact:
    db_dict: "{{ db_dict|default({})|combine({item.name: item}) }}"
  loop: "{{ mysql_databases }}"
- set_fact:
    users_dict: "{{ users_dict|default({})|combine({item.name: item}) }}"
  loop: "{{ mysql_users }}"
- template:
    src: credentials.conf.j2
    dest: "{{ item.path}}/{{ item.db }}.conf"
  loop: "{{ sites }}"

然后，使用正确结构化的数据进行操作是微不足道的。例如模板

$ cat credentials.conf.j2
{% for k,v in db_dict[item.db].iteritems() %}
{{ k }}: {{ v }}
{% endfor %}

{% for k,v in users_dict[item.db].iteritems() %}
{{ k }}: {{ v }}
{% endfor %}

给

$ cat path1/db1.conf 
collation: utf8mb4_unicode_ci
name: db1
encoding: utf8mb4

host: %
password: pass1
db: db1
name: db1
priv: db1.*:ALL

可以删除属性 name从字典。例如

- set_fact:
    db_dict: "{{ db_dict|default({})|
                 combine({item.name: item|dict2items|
                                     rejectattr('key', 'match', 'name')|
                                     list|items2dict}) }}"
  loop: "{{ mysql_databases }}"
- debug:
    var: db_dict

- set_fact:
    users_dict: "{{ users_dict|default({})|
                 combine({item.name: item|dict2items|
                                     rejectattr('key', 'match', 'name')|
                                     list|items2dict}) }}"
  loop: "{{ mysql_users }}"
- debug:
    var: users_dict

给

"db_dict": {
    "db1": {
        "collation": "utf8mb4_unicode_ci", 
        "encoding": "utf8mb4"
    }, 
    "db2": {
        "collation": "utf8mb4_unicode_ci", 
        "encoding": "utf8mb4"
    }, 
    "db3": {
        "collation": "utf8mb4_unicode_ci", 
        "encoding": "utf8mb4"
    }
}

和

"users_dict": {
    "db1": {
        "db": "db1", 
        "host": "%", 
        "password": "pass1", 
        "priv": "db1.*:ALL"
    }, 
    "db2": {
        "db": "db2", 
        "host": "%", 
        "password": "pass2", 
        "priv": "db2.*:ALL"
    }, 
    "db3": {
        "db": "db3", 
        "host": "%", 
        "password": "pass3", 
        "priv": "db3.*:ALL"
    }
}

然后，

- template:
    src: credentials.conf.j2
    dest: "{{ item.path}}/{{ item.db }}.conf"
  loop: "{{ sites }}"

给

$ cat path1/db1.conf 
collation: utf8mb4_unicode_ci
encoding: utf8mb4

host: %
password: pass1
db: db1
priv: db1.*:ALL