Issue with using Omit option - ansible

Question

I am trying configure a attribute only if my_int_http is defined else I dont want it. So I coded it like below:
profiles:
- "{{ my_int_L4 }}"
- "{{ my_int_http | default(omit) }}"
However my execution fail and when check the arguments passed by the code in actual configuration it shows like below:
"profiles": [
"my_example.internal_tcp",
"__omit_place_holder__ef8c5b99e9707c044ac07fda72fa950565f248a4"
So how to pass absolutely no value where it is passing __omit_place_holder_****?

Answer 1

Q: "How to pass absolutely no value where it is passing omit_place_holder ?"
A1: Some filters also work with omit as expected. For example, the play
- hosts: localhost
vars:
test:
- "{{ var1|default(false) }}"
- "{{ var1|default(omit) }}"
tasks:
- debug:
msg: "{{ {'a': item}|combine({'b': true}) }}"
loop: "{{ test }}"
gives
msg:
a: false
b: true
msg:
b: true
As a sidenote, default(omit) is defined type string
- debug:
msg: "{{ item is defined }}"
loop: "{{ test }}"
- debug:
msg: "{{ item|type_debug }}"
loop: "{{ test }}"
give
TASK [debug] *************************************************************
ok: [localhost] => (item=False) =>
msg: true
ok: [localhost] => (item=__omit_place_holder__6e56f2f992faa6e262507cb77410946ea57dc7ef) =>
msg: true
TASK [debug] *************************************************************
ok: [localhost] => (item=False) =>
msg: bool
ok: [localhost] => (item=__omit_place_holder__6e56f2f992faa6e262507cb77410946ea57dc7ef) =>
msg: str
A2: No value in Ansible is YAML null. Quoting:
This is typically converted into any native null-like value (e.g., undef in Perl, None in Python).
(Given my_int_L4=bob). If the variable my_int_http defaults to null instead of omit
profiles:
- "{{ my_int_L4 }}"
- "{{ my_int_http | default(null) }}"
the list profiles will be undefined
profiles: VARIABLE IS NOT DEFINED!
Use None instead
profiles:
- "{{ my_int_L4 }}"
- "{{ my_int_http | default(None) }}"
The variable my_int_http will default to an empty string
profiles:
- bob
- ''
See also section "YAML tags and Python types" in PyYAML Documentation.

Answer 2

You can try something like this,
profiles:
- "{{ my_int_L4 }}"
- "{{ my_int_http | default(None) }}"
This will give you an empty string. And you can add a check while iterating over the profiles.
Please have a look at this GitHub Issue to get more understanding.