Ansible 开发Filters插件之【split】

需求

---

1. 实现python的字符串分割
2. 实现re的正则表达式分割

Filter 类

---

class FilterModule(object):
    ''' A filter to split a string into a list. '''
    def filters(self):
        return {
            'filter_name' : filter_function,
        }

所有的filter类都是上诉构造

• filter_name 是 Ansible Jinja2 filter的name。
• filter_function(string) 是处理字符的方法, 如{{ 'test' | filter_name }}， test字符串会传递给string。

实现代码

---

cat filter_plugins/split.py
import re

def split_string(string, seperator=None, maxsplit=-1):
    try:
        return string.split(seperator, maxsplit)
    except:
        return list(string)

def split_regex(string, seperator_pattern):
    try:
        return re.split(seperator_pattern, string)
    except:
        return list(string)

class FilterModule(object):
    ''' A filter to split a string into a list. '''
    def filters(self):
        return {
            'split' : split_string,
            'split_regex' : split_regex,
        }

Playbook

---

- hosts: localhost
  gather_facts: no
  tasks:
    - debug: msg={{ 'a b c' | split }}
    - debug: msg={{ '1c2c3' | split('c') }}
    - debug: msg={{ 'dev.example.com' | split_regex('\.') }}

主机清单

localhost ansible_connection=local

运行playbook

image.png