Ansible常用Filter

╰半橙微兮° 2023-06-18 13:52 2阅读 0赞

### 文章目录 ###

*  Ansible 常用Filter
 *   *  示例json文件
     *  \`from\_json\`
     *  \`json query filter\`
     *  \`list filters\`
     *  \`\`random number filter\`\`
     *  \`IP address filter\`
     *  \`Hashing filters\`
     *  \`URL Split Filter\`
     *  \`path Filter\`
     *  \`Debug Filters\`
     *  \`Debug Filters\`
 *  参考文档

# Ansible 常用Filter #

Ansible中的过滤器来自Jinja2，用于在模板表达式中转换数据。在写playbook的时候，偶尔需要对变量进行处理，比如在一段json文件中查找某些值进行循环，又比如获取了一段地址但是需要对它进行切分取basename，又比如直接从对一段url进行切分处理，等等等等，在Ansible内部实现了许多Filter对上述的这些场景都提供了比较健全的Filter，这里列出一些常用的Filter，更全面的可以查看ansible的官方文档，和jinja2的文档，地址都已在参考文档章节中给出，

## 示例json文件 ##

// 示例字符串
    // $ cat domain_definition.json
    { 
            "domain": { 
                "cluster": [
                    { 
                        "name": "cluster1"
                    },
                    { 
                        "name": "cluster2"
                    }
                ],
                "server": [
                    { 
                        "name": "server11",
                        "cluster": "cluster1",
                        "port": "8080"
                    },
                    { 
                        "name": "server12",
                        "cluster": "cluster1",
                        "port": "8090"
                    },
                    { 
                        "name": "server21",
                        "cluster": "cluster2",
                        "port": "9080"
                    },
                    { 
                        "name": "server22",
                        "cluster": "cluster2",
                        "port": "9090"
                    }
                ],
                "library": [
                    { 
                        "name": "lib1",
                        "target": "cluster1"
                    },
                    { 
                        "name": "lib2",
                        "target": "cluster2"
                    }
                ]
            }
    }

## `from_json` ##

`from_json filter`从json格式变量中加载成字典变量

# 查看playbook内容，从加载json文件
    $ cat from_json.yml
    - hosts: 192.168.240.33
      gather_facts: no # 本次playbook 不收集fact信息
      tasks:
        - name: from_json filter test
          debug:
            var:  domain_definition
      vars:
        domain_definition: "{ { lookup('file','/home/ansible/ADT/domain_definition.json') | from_json }}"
        
    # 执行
    $ ansible-playbook from_json.yml
    
    PLAY [192.168.240.33] ***********************************************************************************************************************************************
    
    TASK [from_json filter test] ****************************************************************************************************************************************
    ok: [192.168.240.33] => { 
        "domain_definition": { 
            "domain": { 
                "cluster": [
                    { 
                        "name": "cluster1"
                    },
                    { 
                        "name": "cluster2"
                    }
                ],
                "library": [
                    { 
                        "name": "lib1",
                        "target": "cluster1"
                    },
                    { 
                        "name": "lib2",
                        "target": "cluster2"
                    }
                ],
                "server": [
                    { 
                        "cluster": "cluster1",
                        "name": "server11",
                        "port": "8080"
                    },
                    { 
                        "cluster": "cluster1",
                        "name": "server12",
                        "port": "8090"
                    },
                    { 
                        "cluster": "cluster2",
                        "name": "server21",
                        "port": "9080"
                    },
                    { 
                        "cluster": "cluster2",
                        "name": "server22",
                        "port": "9090"
                    }
                ]
            }
        }
    }
    
    PLAY RECAP **********************************************************************************************************************************************************
    192.168.240.33             : ok=1    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

## `json query filter` ##

json查询过滤器,测试的playbook如下，\#注释部分表示对应task的输出信息

$ cat json_query.yml
    ---
    
    - hosts: 192.168.240.33
      gather_facts: no
      vars:
        domain_definition: "{ { lookup('file','/home/ansible/ADT/domain_definition.json') | from_json }}"
      tasks:
        - name: "Display all cluster names"
          debug:
            var:  item
          loop: "{ { domain_definition | json_query('domain.cluster[*].name') }}"
    
    #TASK [Display all cluster names] ************************************************************************************************************************************
    #ok: [192.168.240.33] => (item=cluster1) => { 
    # "ansible_loop_var": "item",
    # "item": "cluster1"
    #}
    #ok: [192.168.240.33] => (item=cluster2) => { 
    # "ansible_loop_var": "item",
    # "item": "cluster2"
    #}
    
    
        - name: "Display all server names"
          debug:
            var: item
          loop: "{ { domain_definition | json_query('domain.server[*].name') }}"
    
    #TASK [Display all server names] *************************************************************************************************************************************
    #ok: [192.168.240.33] => (item=server11) => { 
    # "ansible_loop_var": "item",
    # "item": "server11"
    #}
    #ok: [192.168.240.33] => (item=server12) => { 
    # "ansible_loop_var": "item",
    # "item": "server12"
    #}
    #ok: [192.168.240.33] => (item=server21) => { 
    # "ansible_loop_var": "item",
    # "item": "server21"
    #}
    #ok: [192.168.240.33] => (item=server22) => { 
    # "ansible_loop_var": "item",
    # "item": "server22"
    #}
    #
    
    
        - name: "Display all server ports and names from cluster1"
          debug:
            var: item
          loop: "{ { domain_definition | json_query(server_name_cluster1_query) }}"
          vars:
            server_name_cluster1_query: "domain.server[?cluster=='cluster1'].port"
    
    #TASK [Display all server ports and names from cluster1] *************************************************************************************************************
    #ok: [192.168.240.33] => (item=8080) => { 
    # "ansible_loop_var": "item",
    # "item": "8080"
    #}
    #ok: [192.168.240.33] => (item=8090) => { 
    # "ansible_loop_var": "item",
    # "item": "8090"
    #}
    
    
        - name: "Display all ports from cluster1 as a string"
          debug:
            msg: "{ { domain_definition | json_query('domain.server[?cluster==`cluster1`].port') | join(', ') }}"
    
    #TASK [Display all ports from cluster1 as a string] ******************************************************************************************************************
    #ok: [192.168.240.33] => { 
    # "msg": "8080, 8090"
    #}
    
    
        - name: "Display all server ports and names from cluster1"
          debug:
            var: item
          loop: "{ { domain_definition | json_query(server_name_cluster1_query) }}"
          vars:
            server_name_cluster1_query: "domain.server[?cluster=='cluster2'].{name: name, port: port}"
    
    
    
    #TASK [Display all server ports and names from cluster1] *************************************************************************************************************
    #ok: [192.168.240.33] => (item={u'name': u'server21', u'port': u'9080'}) => { 
    # "ansible_loop_var": "item",
    # "item": { 
    # "name": "server21",
    # "port": "9080"
    # }
    #}
    #ok: [192.168.240.33] => (item={u'name': u'server22', u'port': u'9090'}) => { 
    # "ansible_loop_var": "item",
    # "item": { 
    # "name": "server22",
    # "port": "9090"
    # }
    #}

## `list filters` ##

列表过滤器

# 求列表最小值
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,3,4] | min }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "1"
    }
    # 求列表最大值
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,3,4] | max }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "4"
    }
    # 将列表展开，这个在某些场景下非常有用
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,[3,4]] | flatten }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": [
            1,
            2,
            3,
            4
        ]
    }
    
    # 也可以指定展开多少层
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,[3,[4]]] | flatten(levels=1) }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": [
            1,
            2,
            3,
            [
                4
            ]
        ]
    }
    
    # 对列表去重
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,3,3,3,4,5,5]| unique }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": [
            1,
            2,
            3,
            4,
            5
        ]
    }
    
    # 对比两个列表去除不同的值
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,3,3,3,4,5,5]| difference([1,2,3]) }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": [
            4,
            5
        ]
    }

## `random number filter` ##

随机数生成器

# 60以内随机生成一个整数
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { 60 | random }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "1"
    }
    
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { 60 | random }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "21"
    }
    
    # 从列表中随机选择一个数字
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,4,5] | random }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "5"
    }
    
    $ ansible 192.168.240.33 -m debug -a 'msg="{ { [1,2,4,5] | random }}"'
    192.168.240.33 | SUCCESS => { 
        "msg": "2"
    }

## `IP address filter` ##

ip地址过滤器,此filter需要安装netaddr模块，安装方法如下`pip install netaddr`，否则会报错，报错信息如下：

fatal: [192.168.240.33]: FAILED! => { "msg": "The ipaddr filter requires python's netaddr be installed on the ansible controller"}

示例：

{
       { '192.0.2.1/24' | ipaddr('address') }}

## `Hashing filters` ##

hash过滤器

# 示例playbook
    $ cat hash_filter.yml
    ---
    - hosts: 192.168.240.33
      gather_facts: no
      vars:
        str: 'string'
      tasks:
        - debug:
            msg: "{ { str | hash('md5') }}"
    
    # 执行结果
    $ ansible-playbook hash_filter.yml
    
    PLAY [192.168.240.33] *******************************************************************************************************************
    
    TASK [debug] ****************************************************************************************************************************
    ok: [192.168.240.33] => { 
        "msg": "b45cffe084dd3d20d928bee85e7b0f21"
    }
    
    PLAY RECAP ******************************************************************************************************************************
    192.168.240.33             : ok=1    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

## `URL Split Filter` ##

url切分过滤器

$ cat url_split_filter.yml
    ---
    - hosts: 192.168.240.33
      gather_facts: no
      vars:
        url: 'http://user:password@www.acme.com:9000/dir/index.html?query=term#fragment'
      tasks:
        - name: "get url hostname"
          debug:
            msg: "{ { url | urlsplit('hostname') }}"
            
    # ==> "msg": "www.acme.com"
    
        - name: "get url netloc"
          debug:
            msg: "{ { url | urlsplit('netloc') }}"
    # ==> "user:password@www.acme.com:9000"
        - name: "get url path"
          debug:
            msg: "{ { url | urlsplit('path') }}"
    
    # ==> "msg": "/dir/index.html"
        - name: "get url port"
          debug:
            msg: "{ { url | urlsplit('port') }}"
    
    # ==> "msg": "9000"
    
        - name: "get url scheme"
          debug:
            msg: "{ { url | urlsplit('scheme') }}"
    
    # ==> "msg": "http"
    
        - name: "get url query"
          debug:
            msg: "{ { url | urlsplit('query') }}"
    
    # ==> "msg": "query=term"

## `path Filter` ##

路径filter

# 获取basename
    $ ansible 192.168.240.33 -m debug -a 'msg={ { "/home/archforce/ADT/hosts.ini" | basename }}'
    192.168.240.33 | SUCCESS => { 
        "msg": "hosts.ini"
    }
    
    # 获取目录
    $ ansible 192.168.240.33 -m debug -a 'msg={ { "/home/archforce/ADT/hosts.ini" | dirname }}'
    192.168.240.33 | SUCCESS => { 
        "msg": "/home/archforce/ADT"
    }
    
    # 获取绝对路径
    $ ansible 192.168.240.33 -m debug -a 'msg={ { "./hosts.ini" | realpath }}'
    192.168.240.33 | SUCCESS => { 
        "msg": "/home/ansible/ADT/hosts.ini"
    }

## `Debug Filters` ##

用于debug的filter

$ ansible 192.168.240.33 -m debug -a 'msg={ { "hello world" | type_debug }}'
    192.168.240.33 | SUCCESS => { 
        "msg": "str"
    }

## `Debug Filters` ##

用于debug的filter

$ ansible 192.168.240.33 -m debug -a 'msg={ { "hello world" | type_debug }}'
    192.168.240.33 | SUCCESS => { 
        "msg": "str"
    }

# 参考文档 #

*  Ansible 官方文档：https://docs.ansible.com/ansible/latest/user\_guide/playbooks\_filters.html\#filters-for-formatting-data
 *  jinja2官方文档：https://jinja.palletsprojects.com/en/2.10.x/templates/\#builtin-filters
 *  ip address filter官方文档：https://docs.ansible.com/ansible/latest/user\_guide/playbooks\_filters\_ipaddr.html