如何使用Jinja2过滤器清理Ansible Playbook中的字典值

Question

I have a playbook task that returns a list of dicts like this:

mydict:
  - { "ip": "192.168.0.1", "mac": "00324a:ac6789" }
  - { "ip": "192.168.0.2", "mac": "00324a.ac6790" }
  - { "ip": "192.168.0.3", "mac": "00:32:4a:ac:67:91" }

I would like to scrub the mac addresses so they all appear in the same format, something like:

- set_fact:
    myarp: "{{ mydict|map(attribute='mac')|ipaddr('eui48')  }}"

would return:

myarp:
  - { "ip": "192.168.0.1", "mac": "00-32-4A-AC-67-89" }
  - { "ip": "192.168.0.2", "mac": "00-32-4A-AC-67-90" }
  - { "ip": "192.168.0.3", "mac": "00-32-4A-AC-67-91" }

Answer 1

It won't work with map because this filter either only returns one specific attribute OR applies another filter to each element of the list. But you can not apply a filter to a specific attribute of each list element. I don't think there is a way to do that with the built-in filters and if there is one, it gets too unreadable.

The best you can do here is to write a custom filter plugin :

from ansible import errors
from jinja2.filters import environmentfilter
import re

class FilterModule(object):
    def filters(self):
        return {
            'scrubmac': self.scrubmac
        }
    def scrubmac(*args):
        data = args[1]
        for item in data:
            mac = re.sub('[^A-z0-9]', '', item['mac'])
            item['mac'] = re.sub('(.{2})(?=.)', '\\1-', mac)
        return data

_{That's for Ansible 2. Not sure, might need some small changes for Ansible 1.}

Then call it as

- set_fact:
    myarp: "{{ mydict | scrubmac }}"