从 Ansible 中的字典列表中提取值

Question

我有这个剧本，我需要找到一种方法来显示

prerequisite

下的字典列表的值，因为我知道我们有不同的键名称。如何显示这些值并保持与我的剧本相同的语法？

预期输出：

"linux/mysql/8.0.19/prerequis/mysql-community-common-8.0.19-1.el7.x86_64.rpm"
"mysql-community-common-8.0.19-1.el7.x86_64"
"linux/mysql/8.0.19/prerequis/mysql-community-libs-8.0.19-1.el7.x86_64.rpm"
"mysql-community-libs-8.0.19-1.el7.x86_64"
"linux/mysql/8.0.19/prerequis/mysql-community-client-8.0.11-1.el7.x86_64.rpm"
"mysql-community-client-8.0.11-1.el7.x86_64"
"linux/mysql/8.0.19/prerequis/mysql-shell-8.0.19-1.el7.x86_64.rpm"
"mysql-shell-8.0.19-1.el7.x86_64"

---

- name: "extract values from a list of dictionaries"
 hosts: localhost
 tasks:
 - name: "adding variables"
   set_fact:
     products:
       mysql_8_0_19:
         CentOS_7:
           signature: "mysql-community-server-8.0.19-1.el7.x86_64"
           url: "linux/mysql/8.0.19/mysql-community-server-8.0.19-1.el7.x86_64.rpm"
         pymysql_url: "linux/mysql/8.0.19/prerequis/PyMySQL-0.9.3.tar.gz"
         prerequisite:
         - mysql_c_common_url: "linux/mysql/8.0.19/prerequis/mysql-community-common-8.0.19-1.el7.x86_64.rpm"
           mysql_c_common_signature: "mysql-community-common-8.0.19-1.el7.x86_64"
         - mysql_c_libs_url: "linux/mysql/8.0.19/prerequis/mysql-community-libs-8.0.19-1.el7.x86_64.rpm"
           mysql_c_libs_signature: "mysql-community-libs-8.0.19-1.el7.x86_64"
         - mysql_c_client_url: "linux/mysql/8.0.19/prerequis/mysql-community-client-8.0.11-1.el7.x86_64.rpm"
           mysql_c_client_signature: "mysql-community-client-8.0.11-1.el7.x86_64"
         - mysql_shell_url: "linux/mysql/8.0.19/prerequis/mysql-shell-8.0.19-1.el7.x86_64.rpm"
           mysql_shell_signature: "mysql-shell-8.0.19-1.el7.x86_64"

 - name: " display "
   debug:
     msg: "{{ item }}"
   with_items: "{{ products.mysql_8_0_19.prerequisite }}"'

Answer 1

在 Ansible 中使用一组“未知”键获取字典的值通常需要使用 dict2items

。

您的用例确实符合要求，您只需对

map

列表的所有元素进行

prerequisite

过滤器，然后 flatten

 它，最后使用另一个 

map 过滤器提取值。因此，您可以通过任务实现所需的目标：

- debug:
    msg: "{{ item }}"
  loop: >-
    {{ 
      products.mysql_8_0_19.prerequisite 
      | map('dict2items') 
      | flatten 
      | map(attribute='value') 
    }}

如果您使用旧版本的 Ansible 并收到类似 | list

 的错误，您可能需要在末尾添加 

<generator object do_map at 0x7f3xxxxx> 过滤器

给定任务：

---

- debug:
    var: >-
      products.mysql_8_0_19.prerequisite
      | map('dict2items')
      | flatten
      | map(attribute='value')
  vars:
    products:
      mysql_8_0_19:
        prerequisite: "{{ prerequisite }}"
    prerequisite:
      - mysql_c_common_url: >-
          linux/mysql/8.0.19/prerequis{#- allows line wrap -#}
          /mysql-community-common-8.0.19-1.el7.x86_64.rpm
        mysql_c_common_signature: >-
          mysql-community-common-8.0.19-1.el7.x86_64
      - mysql_c_libs_url: >-
          linux/mysql/8.0.19/prerequis{#- allows line wrap -#}
          /mysql-community-libs-8.0.19-1.el7.x86_64.rpm
        mysql_c_libs_signature: >-
          mysql-community-libs-8.0.19-1.el7.x86_64
      - mysql_c_client_url: >-
          linux/mysql/8.0.19/prerequis{#- allows line wrap -#}
          /mysql-community-client-8.0.11-1.el7.x86_64.rpm
        mysql_c_client_signature: >-
          mysql-community-client-8.0.11-1.el7.x86_64
      - mysql_shell_url: >-
          linux/mysql/8.0.19/prerequis{#- allows line wrap -#}
          /mysql-shell-8.0.19-1.el7.x86_64.rpm
        mysql_shell_signature: >-
          mysql-shell-8.0.19-1.el7.x86_64

这产生：

- linux/mysql/8.0.19/prerequis/mysql-community-common-8.0.19-1.el7.x86_64.rpm
- mysql-community-common-8.0.19-1.el7.x86_64
- linux/mysql/8.0.19/prerequis/mysql-community-libs-8.0.19-1.el7.x86_64.rpm
- mysql-community-libs-8.0.19-1.el7.x86_64
- linux/mysql/8.0.19/prerequis/mysql-community-client-8.0.11-1.el7.x86_64.rpm
- mysql-community-client-8.0.11-1.el7.x86_64
- linux/mysql/8.0.19/prerequis/mysql-shell-8.0.19-1.el7.x86_64.rpm
- mysql-shell-8.0.19-1.el7.x86_64