In Ansible, how can I iterate over stdout with an array? - ansible

Question

Ansible v2.6.3
I have the simple task, which gets the AWS ARNs in my jenkins ECS cluster
tasks:
- command: aws ecs list-container-instances --cluster jenkins
register: jenkins_ecs_containers
- debug: var=jenkins_ecs_containers.stdout
and has the following output
TASK [debug] *******************************************************************
ok: [localhost] => {
"jenkins_ecs_containers.stdout": {
"containerInstanceArns": [
"arn:aws:ecs:us-east-1:arn0",
"arn:aws:ecs:us-east-1:arn1"
]
}
}
How can I iterate over the ARNs? I tried
- debug: var=item
with_items: jenkins_ecs_containers.stdout.containerInstanceArns
gives
TASK [debug] *******************************************************************
ok: [localhost] => (item=jenkins_ecs_containers.stdout.containerInstanceArns) => {
"item": "jenkins_ecs_containers.stdout.containerInstanceArns"
}
or
- debug: var=item
with_items: "{{ jenkins_ecs_containers.stdout.containerInstanceArns }}"
gives
TASK [debug] *******************************************************************
fatal: [localhost]: FAILED! => {"msg": "'ansible.utils.unsafe_proxy.AnsibleUnsafeText object' has no attribute 'containerInstanceArns'"}
to retry, use: --limit #/Users/cfouts/git-repos/ansible/playbooks/loop.retry
Thanks!

Answer 1

I created a file with your output. So I used set_fact. Otherwise, it's just a string, not a JSON object:
tasks:
- command: cat files/stdout.txt
register: result
- debug: var=result.stdout
- set_fact:
jenkins_ecs_containers: "{{ result.stdout }}"
- debug:
msg: "{{ item }}"
with_items: "{{ jenkins_ecs_containers.containerInstanceArns }}"
This gave me the following output:
PLAY [localhost] ***************************************************************
TASK [Gathering Facts] *********************************************************
ok: [localhost]
TASK [command] *****************************************************************
changed: [localhost]
TASK [debug] *******************************************************************
ok: [localhost] => {
"result.stdout": {
"containerInstanceArns": [
"arn:aws:ecs:us-east-1:arn0",
"arn:aws:ecs:us-east-1:arn1"
]
}
}
TASK [set_fact] ****************************************************************
ok: [localhost]
TASK [debug] *******************************************************************
ok: [localhost] => (item=None) => {
"msg": "arn:aws:ecs:us-east-1:arn0"
}
ok: [localhost] => (item=None) => {
"msg": "arn:aws:ecs:us-east-1:arn1"
}
PLAY RECAP *********************************************************************
localhost : ok=5 changed=1 unreachable=0 failed=0

Answer 2

You can iterate over like this:
- debug:
msg: "{{ item[1] }}"
with_subelements:
- "{{ jenkins_ecs_containers }}"
- containerInstanceArns
Go through this link, it will make it clearer.