How do I get Ansible's json_query to return a value from this JSON document - ansible

Question

After several hours of beating my head against this (not to mention leaving it for a day) I'm pretty much stumped on trying to figure out why I can't JMESPath to return a value in Ansible.
I have a task which runs a shell command and returns the following output:
[
{
"ansible_loop_var": "item",
"changed": false,
"cmd": [
"pvesh",
"create",
"/access/users/user#pve/token/pve-apikey",
"-privsep=0",
"--output=json"
],
"delta": "0:00:00.707130",
"end": "2022-09-22 12:28:43.746253",
"failed": false,
"invocation": {
"module_args": {
"_raw_params": "pvesh create /access/users/\"user#pve\"/token/\"pve-apikey\" -privsep=0 --output=json",
"_uses_shell": false,
"argv": null,
"chdir": null,
"creates": null,
"executable": null,
"removes": null,
"stdin": null,
"stdin_add_newline": true,
"strip_empty_ends": true,
"warn": false
}
},
"item": {
"token": "pve-apikey",
"user": "user#pve"
},
"msg": "",
"rc": 0,
"start": "2022-09-22 12:28:43.039123",
"stderr": "",
"stderr_lines": [],
"stdout": "{\"full-tokenid\":\"user#pve!pve-apikey\",\"info\":{\"privsep\":\"0\"},\"value\":\"dc2aa48f-daf6-4efe-b95e-83774a588988\"}",
"stdout_lines": [
"{\"full-tokenid\":\"user#pve!pve-apikey\",\"info\":{\"privsep\":\"0\"},\"value\":\"dc2aa48f-daf6-4efe-b95e-83774a588988\"}"
]
}
]
I'm now trying to obtain the UUID returned as value in the stdout_line using json_query and this is far as I can get:
- debug:
msg: "{{ token | community.general.json_query(query) }}"
vars:
query: '[].stdout'
This json_query returns the following output:
"msg": [
"{\"full-tokenid\":\"tfuser#pve!tfe-pve-apikey\",\"info\":{\"privsep\":\"0\"},\"value\":\"e47e82d4-6798-47ea-9592-c7cf55cc8b61\"}"
]
I believe that this is a list, so I've tried extending the json_query as [].stdout[].value but that returns null. I've tried various permutations but so far nothing seems to work.
Any advice on how to proceed would be very welcome!

Answer 1

The items of the list stdout_lines are strings. You can test it. For example,
- debug:
var: output.0.stdout_lines.0|type_debug
gives
output.0.stdout_lines.0|type_debug: AnsibleUnsafeText
Convert the items to dictionaries. For example
- debug:
var: output.0.stdout_lines.0|from_yaml
gives
output.0.stdout_lines.0|from_yaml:
full-tokenid: user#pve!pve-apikey
info:
privsep: '0'
value: dc2aa48f-daf6-4efe-b95e-83774a588988
To get the UUID, declare the variable
UUID: "{{ output|map(attribute='stdout_lines')|
map('map', 'from_yaml')|list|
json_query('[].value') }}"
This gives the list of the values
UUID:
- dc2aa48f-daf6-4efe-b95e-83774a588988
Example of a complete playbook for testing
- hosts: localhost
vars:
output: "{{ lookup('file', 'output.json') }}"
UUID: "{{ output|map(attribute='stdout_lines')|
map('map', 'from_yaml')|list|
json_query('[].value') }}"
tasks:
- debug:
var: output.0.stdout_lines.0|type_debug
- debug:
var: output.0.stdout_lines.0|from_yaml
- debug:
var: UUID