fact_diff

Collection Note

This module is part of the ansible.utils collection. To install the collection, use:

ansible-galaxy collection install ansible.utils

Added in version 2.12.0.

Synopsis

• Compare two facts or variables and get a diff.

Parameters

Parameter	Defaults / Choices	Comments
after raw required		The second fact to be used in the comparison.
before raw required		The first fact to be used in the comparison.
common bool		Show all common lines.
plugin dict		Configure and specify the diff plugin to use
plugin.name	Default: ansible.utils.native	The diff plugin to use, in fully qualified collection name format.
plugin.vars		Parameters passed to the diff plugin.

Examples

- name: Set fact
  ansible.builtin.set_fact:
    before:
      a:
        b:
          c:
            d:
              - 0
              - 1
    after:
      a:
        b:
          c:
            d:
              - 2
              - 3

- name: Show the difference in json format
  ansible.builtin.set_fact:
    result: "{{before | ansible.utils.fact_diff(after)}}"

# TASK [Show the difference in json format] **********************************************************************************************
# ok: [localhost] => {
#     "ansible_facts": {
#         "result": [
#             "--- before",
#             "+++ after",
#             "@@ -3,8 +3,8 @@",
#             "         "b": {",
#             "             "c": {",
#             "                 "d": [",
#             "-                    0,",
#             "-                    1",
#             "+                    2,",
#             "+                    3",
#             "                 ]",
#             "             }",
#             "         }",
#             ""
#         ]
#     },
#     "changed": false
# }

- name: Set fact
  ansible.builtin.set_fact:
    before: "{{ before|ansible.utils.to_paths }}"
    after: "{{ after|ansible.utils.to_paths }}"

- name: Show the difference in path format
  ansible.builtin.set_fact:
    result: "{{before | ansible.utils.fact_diff(after)}}"

# TASK [Show the difference in path format] **********************************************************************************************
# ok: [localhost] => {
#     "ansible_facts": {
#         "result": [
#             "--- before",
#             "+++ after",
#             "@@ -1,4 +1,4 @@",
#             " {",
#             "-    "a.b.c.d[0]": 0,",
#             "-    "a.b.c.d[1]": 1",
#             "+    "a.b.c.d[0]": 2,",
#             "+    "a.b.c.d[1]": 3",
#             " }",
#             ""
#         ]
#     },
#     "changed": false
# }

- name: Set fact
  ansible.builtin.set_fact:
    before: "{{ before|to_nice_yaml }}"
    after: "{{ after|to_nice_yaml }}"

- name: Show the difference in yaml format
  ansible.builtin.set_fact:
    result: "{{before | ansible.utils.fact_diff(after)}}"

# TASK [Show the difference in yaml format] **********************************************************************************************
# ok: [localhost] => {
#     "ansible_facts": {
#         "result": [
#             "--- before",
#             "+++ after",
#             "@@ -1,2 +1,2 @@",
#             "-a.b.c.d[0]: 0",
#             "-a.b.c.d[1]: 1",
#             "+a.b.c.d[0]: 2",
#             "+a.b.c.d[1]: 3",
#             ""
#         ]
#     },
#     "changed": false
# }

Return Values

Key	Data Type	Description	Returned
result	list	Returns diff between before and after facts.

Authors

• Ashwini Mhatre ((@amhatre))