ansible using loop and multiple variables

Question

i am using "shell:" to get some data by looping over "with_items:" and registering it as another variable. Later using "lineinfile:" i am trying to apply the contents of earlier variable,but not able to use "{{variable.stdout}}" as it is showing as undefined in "with_items:"

Is there a way to tell ansible that for "variable.stdout" don't look in "with_items:"

---
- include_vars: /root/template.yml

- name: Getting MAC
  shell: "cat /sys/class/net/{{item.name}}/address"
  register: mac
  with_items:
  - "{{ interfaces_ipv4 }}"

- name: Setting MAC
   lineinfile:
   state=present
   dest=/etc/sysconfig/network-scripts/ifcfg-{{item.name}}
   regexp='^HWADDR=.*'
   line="HWADDR={{mac.stdout}}"
  with_items:
   - "{{ interfaces_ipv4 }}"
  tags:
   - set_mac

Contents of variable file

#/root/tempplate.yml

- name: ens35
  bootproto: dhcp
- name: ens34
  bootproto: none

When executing:

TASK: [mac | Setting MAC] ***************************************************** fatal: [192.168.211.146] => One or more undefined variables: 'dict' object has no attribute 'stdout'

FATAL: all hosts have already failed -- aborting

Answer 1

register works a bit differently when used inside loops (see here). In that case, your variable will have a results item, which is a list with the result of each iteration as items. Each item in that list will also have an item item, with the element iterated on.

For example:

mac: {
    msg: "All items completed",
    results: [
        {
          changed: True,
          stdout: "some_stdout",
          item: {
               name: "some_name1"
          }
        },
        {
          changed: True,
          stdout: "some_stdout2",
          item: {
               name: "some_name2"
          }
        }
    ]
}

You could then loop over that instead of the original list:

- name: Setting MAC
  lineinfile:
     state=present
     dest=/etc/sysconfig/network-scripts/ifcfg-{{item.item.name}}
     regexp='^HWADDR=.*'
     line="HWADDR={{item.stdout}}"
  with_items: mac.results
  tags:
   - set_mac