How to write varibles/hard code values in nested json in ansible? - ansible

Question

I'm trying to create a json file with hard codes valuesas a output in nested json.But the second play is overwriting the first play value.So do we have any best option to do this?
I have tried with to_nice_json template to copy the variable to json file.But not able to keep multiple variable values in imported_var to copy to json file
---
- hosts: localhost
connection: local
gather_facts: false
tasks:
- name: load var from file
include_vars:
file: /tmp/var.json
name: imported_var
- name: Checking mysqld status
shell: service mysqld status
register: mysqld_stat
ignore_errors: true
- name: Checking mysqld status
shell: service httpd status
register: httpd_stat
ignore_errors: true
- name: append mysqld status to output json
set_fact:
imported_var: "{{ imported_var | combine({ 'status_checks':[{'mysqld_status': (mysqld_stat.rc == 0)|ternary('good', 'bad') }]})}}"
# - name: write var to file
# copy:
# content: "{{ imported_var | to_nice_json }}"
# dest: /tmp/final.json
- name: append httpd status to output json
set_fact:
imported_var: "{{ imported_var| combine({ 'status_checks':[{'httpd_status': (httpd_stat.rc == 0)|ternary('good', 'bad') }]})}}"
# - debug:
# var: imported_var
- name: write var to file
copy:
content: "{{ imported_var | to_nice_json }}"
dest: /tmp/final.json
Expected result:
{
"status_checks": [
{
"mysqld_status": "good"
"httpd_status": "good"
}
]
}
Actual result:
{
"status_checks": [
{
"httpd_status": "good"
}
]
}

Answer 1

You're trying to perform the sort of data manipulation that Ansible really isn't all that good at. Any time you attempt to modify an existing variable -- especially if you're trying to set a nested value -- you're making life complicated. Having said that, it is possible to do what you want. For example:
---
- hosts: localhost
gather_facts: false
vars:
imported_var: {}
tasks:
- name: Checking sshd status
command: systemctl is-active sshd
register: sshd_stat
ignore_errors: true
- name: Checking httpd status
command: systemctl is-active httpd
register: httpd_stat
ignore_errors: true
- set_fact:
imported_var: "{{ imported_var|combine({'status_checks': []}) }}"
- set_fact:
imported_var: >-
{{ imported_var|combine({'status_checks':
imported_var.status_checks + [{'sshd_status': (sshd_stat.rc == 0)|ternary('good', 'bad')}]}) }}
- set_fact:
imported_var: >-
{{ imported_var|combine({'status_checks':
imported_var.status_checks + [{'httpd_status': (httpd_stat.rc == 0)|ternary('good', 'bad')}]}) }}
- debug:
var: imported_var
On my system (which is running sshd but is not running httpd, this will output:
TASK [debug] **********************************************************************************
ok: [localhost] => {
"imported_var": {
"status_checks": [
{
"sshd_status": "good"
},
{
"httpd_status": "bad"
}
]
}
}
You could dramatically simplify the playbook by restructuring your data. Make status_checks a top level variable, and instead of having it be a list, have it be a dictionary that maps a service name to the corresponding status. Combine this with some loops and you end up with something that is dramatically simpler:
---
- hosts: localhost
gather_facts: false
tasks:
# We can use a loop here instead of writing a separate task
# for each service.
- name: Checking service status
command: systemctl is-active {{ item }}
register: services
ignore_errors: true
loop:
- sshd
- httpd
# Using a loop in the previous task means we can use a loop
# when creating the status_checks variable, which again removes
# a bunch of duplicate code.
- name: set status_checks variable
set_fact:
status_checks: "{{ status_checks|default({})|combine({item.item: (item.rc == 0)|ternary('good', 'bad')}) }}"
loop: "{{ services.results }}"
- debug:
var: status_checks
The above will output:
TASK [debug] **********************************************************************************************************************************************************************************
ok: [localhost] => {
"status_checks": {
"httpd": "bad",
"sshd": "good"
}
}
If you really want to add this information to your imported_var, you can do that in a single task:
- set_fact:
imported_var: "{{ imported_var|combine({'status_checks': status_checks}) }}"