Ansible nested variables syntax issue, error "dict object has no attribute" - variables

Question

I have the following data inside of Ansible variable server_info, set via register at the end of a task;
ok: [server123] => {
"msg": {
"changed": false,
"failed": false,
"instances": [
{
"ami_launch_index": 0,
"architecture": "x86_64",
"block_device_mappings": [
{
"device_name": "/dev/sda1",
"ebs": {
"attach_time": "2021-02-11T11:48:30+00:00",
"delete_on_termination": false,
"status": "attached",
"volume_id": "vol-5436546546"
}
},
{
"device_name": "/dev/sda2",
"ebs": {
"attach_time": "2021-02-11T11:48:30+00:00",
"delete_on_termination": false,
"status": "attached",
"volume_id": "vol-3546456535"
}
}
],
"capacity_reservation_specification": {
"capacity_reservation_preference": "open"
},
"client_token": "",
"cpu_options": {
"core_count": 2,
"threads_per_core": 1
},
"ebs_optimized": false,
"ena_support": true,
"enclave_options": {
"enabled": false
},
"hibernation_options": {
"configured": false
},
"hypervisor": "xen",
"iam_instance_profile": {
"arn": "arn:aws:iam::6346346356:instance-profile/bla",
"id": "SXIUIAHFKBAFIUAEKBADF"
},
"image_id": "ami-65754765475476",
"instance_id": "i-4657654765476547765",
"instance_type": "t2.large",
"key_name": "bla",
"launch_time": "2021-02-15T08:51:44+00:00",
"maintenance_options": {
"auto_recovery": "default"
},
etc... etc...
}
]
}
}
I am attempting to retrieve the value of "instance_id", however I get the following error;
- name: "Instance ID"
debug:
msg: "{{ server_info.instances.instance_id }}"
TASK [Instance ID]
************************************************************************************************************ fatal: [server123]: FAILED! => {"msg": "The task includes an option
with an undefined variable. The error was: 'list object' has no
attribute 'instance_id'\n\nThe error appears to be in
'/ansible/testing.yml': line 38, column 7,
but may\nbe elsewhere in the file depending on the exact syntax
problem.\n\nThe offending line appears to be:\n\n\n - name:
"Instance ID"\n ^ here\n"}
Where am I going wrong in my nested variable retrieval syntax?
Thank you.

Answer 1

See if the below code works
- name: get instance id
set_fact:
new_result: "{{ server_info.instances['instances'] }}"
register: filterd_result
- name: get all ids
vars:
reduce_query: >-
[].{
instance_id: instance_id
}
names: "{{ new_result | json_query(reduce_query)}}"
register: result_names
no_log: true
debug:
var: names
- name: display result
debug:
msg: "{{ result_names.names | map(attribute='instance_id') | flatten }}"

Answer 2

just modify your task:
- name: "Instance ID"
debug:
msg: "{{ server_info.instances.0.instance_id }}"
i suppose instances is an array with only one record ...
if you have more records in array you could use map:
- name: find all instances
debug:
msg:
- "==========================="
- "List of instances id"
- "==========================="
- '{{ server_info.instances | map(attribute="instance_id")|list}}'
- ""