Insert lines in a file from an other file lines in Ansible - linux

Question

I would copy lines from a file /tmp/test1 to a file /tmp/test2
the /tmp/test1 contains:
argument1
argument2
#test1
#test2
#test3
the /tmp/test2 contains:
argument1.1
argument2192
#example
#test2
#example1
So my main goal is to insert every line that doesn't exist in /tmp/test2 from file /tmp/test1
and that the line added must be added at the end of the last line which is containing the same begin of line: ^[[:alpha:]] and ^#, so /tmp/test2 should look like this:
argument1.1
argument2192
argument1
argument2
#example
#test2
#example1
#test1
#test3
I created this playbook but it doesn't do what i am looking for:
- name: check test1 content
command: cat /tmp/test1
register: tmp_content
- name: insert line
lineinfile:
path: /tmp/test2
line: '{{item}}'
insertafter: "^#*"
loop: "{{tmp_content.stdout_lines}}"

Answer 1

1) "Insert every line that doesn't exist in /tmp/test2 from file /tmp/test1"
2) "The line added must be added at the end of the last line which is containing the same beginning."
A: The task below does the job. If the first character is # the line is inserted at the end of the file. Otherwise, the line is inserted before the first line starting with #. The parameters insertafter and insertbefore may not be used together. The negative options omit make the parameters insertafter and insertbefore mutually exclusive
- name: insert line
lineinfile:
path: /tmp/test2
line: "{{ item }}"
insertafter: "{{ (item.0 == '#')|ternary('EOF', omit) }}"
insertbefore: "{{ (item.0 != '#')|ternary('^#.*$', omit) }}"
firstmatch: true
loop: "{{ tmp_content.stdout_lines }}"
Notes
Example of a complete playbook for testing
shell> cat pb.yml
- hosts: localhost
tasks:
- name: check test1 content
command: cat /tmp/test1
register: tmp_content
changed_when: false
- name: insert line
lineinfile:
path: /tmp/test2
line: "{{ item }}"
insertafter: "{{ (item.0 == '#')|ternary('EOF', omit) }}"
insertbefore: "{{ (item.0 != '#')|ternary('^#.*$', omit)}}"
firstmatch: true
loop: "{{ tmp_content.stdout_lines }}"
The playbook is idempotent. See the output of the diff_mode below
shell> ansible-playbook pb.yml --diff
...
TASK [insert line] *************************************************
--- before: /tmp/test2 (content)
+++ after: /tmp/test2 (content)
## -1,5 +1,6 ##
argument1.1
argument2192
+argument1
#example
#test2
#example1
changed: [localhost] => (item=argument1)
--- before: /tmp/test2 (content)
+++ after: /tmp/test2 (content)
## -1,6 +1,7 ##
argument1.1
argument2192
argument1
+argument2
#example
#test2
#example1
changed: [localhost] => (item=argument2)
--- before: /tmp/test2 (content)
+++ after: /tmp/test2 (content)
## -5,3 +5,4 ##
#example
#test2
#example1
+#test1
changed: [localhost] => (item=#test1)
ok: [localhost] => (item=#test2)
--- before: /tmp/test2 (content)
+++ after: /tmp/test2 (content)
## -6,3 +6,4 ##
#test2
#example1
#test1
+#test3
changed: [localhost] => (item=#test3)
Brute force option
Read the files
- command: cat /tmp/test1
register: test1
- command: cat /tmp/test2
register: test2
Declare the variables
l1_alpha: "{{ test1.stdout_lines|select('match', '^[^#].*$') }}"
l1_glyph: "{{ test1.stdout_lines|select('match', '^#.*$') }}"
l2_alpha: "{{ test2.stdout_lines|select('match', '^[^#].*$') }}"
l2_glyph: "{{ test2.stdout_lines|select('match', '^#.*$') }}"
l1_alpha_diff: "{{ l1_alpha|difference(l2_alpha) }}"
l1_glyph_diff: "{{ l1_glyph|difference(l2_glyph) }}"
result: "{{ l2_alpha + l1_alpha_diff + l2_glyph + l1_glyph_diff }}"
This gives the expected result
- debug:
msg: |
{% for line in result %}
{{ line }}
{% endfor %}
msg: |-
argument1.1
argument2192
argument1
argument2
#example
#test2
#example1
#test1
#test3
Write it to a file
- copy:
dest: /tmp/test2
content: |
{% for line in result %}
{{ line }}
{% endfor %}
gives
shell> cat /tmp/test2
argument1.1
argument2192
argument1
argument2
#example
#test2
#example1
#test1
#test3
Example of a complete playbook for testing
shell> cat pb.yml
- hosts: localhost
vars:
l1_alpha: "{{ test1.stdout_lines|select('match', '^[^#].*$') }}"
l1_glyph: "{{ test1.stdout_lines|select('match', '^#.*$') }}"
l2_alpha: "{{ test2.stdout_lines|select('match', '^[^#].*$') }}"
l2_glyph: "{{ test2.stdout_lines|select('match', '^#.*$') }}"
l1_alpha_diff: "{{ l1_alpha|difference(l2_alpha) }}"
l1_glyph_diff: "{{ l1_glyph|difference(l2_glyph) }}"
result: "{{ l2_alpha + l1_alpha_diff + l2_glyph + l1_glyph_diff }}"
tasks:
- command: cat /tmp/test1
register: test1
changed_when: false
- command: cat /tmp/test2
register: test2
changed_when: false
- copy:
dest: /tmp/test2
content: |
{% for line in result %}
{{ line }}
{% endfor %}
The playbook is idempotent.