ansible, jinja template with loops, losing newlines [duplicate] - ansible

Question

This question already has answers here:
How do I get an Ansible template to honor new lines after a conditional
(5 answers)
Closed 4 years ago.
Trying to build a JSON file from a template. It works ok as such, but for some reason newlines within loop constructs go missing, which I find rather irksome; the file "works" (is machine readable just fine), but for human consumption it's pretty ill-suited.
Here's my template:
{
"Users":
[
{% for username,user in _vpn_user_accounts.items() %}
{
"Name" : "{{ user.name }}",
"Hash" : "{{ user.hash }}",
"Cns" : [
{% for cn in user.cns.get(server_name, []) %}
"{{ cn }}"{% if not loop.last -%},{% endif %}
{% endfor %}
],
"key_ids" : [
{% for key in user.get( 'keys' , []) %}
{% if key.public is defined %}
"{{ key.public }}"{% if not loop.last %},{% endif %}
{% endif %}
{% endfor %}
],
"comment" : "{{ user.get( 'comment', '' ) }}"
} {% if not loop.last %},{% endif %}
{% endfor %}
]
}
Here's some sample data:
- andrej:
name: "andrej"
hash: "$2b$10$8EF3H.../Wj0RchEqU6"
cns:
h:
- "andrej_linux_h_201808171440"
- "andrej_linuxvm_h_201809131031"
- "andrej_mac_h_201808171441"
- "andrej_phone_h_201808171441"
w:
- "andrej_linux_w_201808171439"
- "andrej_linuxvm_w_201809131031"
- "andrej_mac_w_201808171441"
- "andrej_phone_w_201808171441"
keys:
- name: "andrej"
public: "kbjrvtni"
- name: "andrej2"
public: "ijrltifu"
- name: "andrej3"
public: "rbcvncbt"
comment: "systems"
This is my desired outcome (running against server "w"):
{
"Users":
[
{
"Name" : "andrej",
"Hash" : "$2b$10$8EF3H.../Wj0RchEqU6",
"Cns" : [
"andrej_linux_w_201808171439",
"andrej_linuxvm_w_201809131031",
"andrej_mac_w_201808171441",
"andrej_phone_w_201808171441"
],
"key_ids" : [
"kbjrvtni",
"ijrltifu",
"rbcvncbt"
],
"comment" : "systems guy"
}
]
}
This is what I get:
{
"Users":
[
{
"Name" : "andrej",
"Hash" : "$2b$10$8EF3H.../Wj0RchEqU6",
"Cns" : [
"andrej_linux_w_201808171439", "andrej_linuxvm_w_201809131031", "andrej_mac_w_201808171441", "andrej_phone_w_201808171441" ],
"key_ids" : [
"kbjrvtni", "ijrltifu", "rbcvncbt" ],
"comment" : "systems guy"
}
]
}
I have experimented with #Jinja2: trim_blocks and #Jinja2: keep_newline, neither of which showed the desired result. Well, trim_blocks kind of did, but it also gave me a bunch of empty lines where the jinja conditionals were ... unsatisfactory.
Any hints on how to resolve this? As I said, it works, but it irks me immensely that I can't get human readable, nice output.

Answer 1

And this little change actually made the problem go away in the end.
#jinja2: trim_blocks:False
{
"Users":
[
{% for username,user in _vpn_user_accounts.items() %}
{
"Name" : "{{ user.name }}",
"Hash" : "{{ user.hash }}",
"Cns" : [
{%- for cn in user.cns.get(server_name, []) %}
"{{ cn }}"{% if not loop.last -%},{% endif %}
{%- endfor %}
],
"key_ids" : [
{%- for key in user.get( 'keys' , []) %}
{% if key.public is defined %}
"{{ key.public }}"{% if not loop.last %},{% endif %}
{% endif %}
{%- endfor %}
],
"comment" : "{{ user.get( 'comment', '' ) }}"
} {% if not loop.last %},{% endif %}
{% endfor %}
]
}