How to Club multiple ansible condition into one based on the set_facts - azure

Question

While going through one of the SO post for Ansible, was interested an usage of set_fact with different conditional checks.
However, I answered on the post based on my approach, but, I still see there can be an improvement to club multiple conditions for similar task like determine the location resource group and vnet.
Below is the playbook and variables file azure_vars.yml
Playbook:
---
- name: create azure vm
hosts: localhost
connection: local
tasks:
- include_vars: azure_vars.yml
- set_fact:
host: "{{ azure_vm_name.split('.') }}"
- set_fact:
domain: "{{ host.1 }}.{{ host.2 }}"
- name: Domain
debug:
msg: "{{ domain }}"
- set_fact:
location: "{{ azure_location[0] }}"
when: 'domain == azure_domain[0]'
- set_fact:
location: "{{ azure_location[1] }}"
when: 'domain == azure_domain[1]'
- set_fact:
location: "{{ azure_location[2] }}"
when: 'domain == azure_domain[2]'
- name: Location
debug:
msg: "{{ location }}"
- set_fact:
res_group: "{{ azure_res_group[0] }}"
when: 'domain == azure_domain[0]'
- set_fact:
res_group: "{{ azure_res_group[1] }}"
when: 'domain == azure_domain[1]'
- set_fact:
res_group: "{{ azure_res_group[2] }}"
when: 'domain == azure_domain[2]'
- name: Resource Group
debug:
msg: "{{ res_group }}"
- set_fact:
vnet: "{{ azure_nprod_vnet }}"
when: 'domain == azure_domain[0]'
- set_fact:
vnet: "{{ azure_prod03_vnet }}"
when: 'domain == azure_domain[2]'
- set_fact:
vnet: "{{ azure_prod02_vnet }}"
when: 'domain == azure_domain[1]'
- name: Vnet
debug:
msg: "{{ vnet }}"
Variable files: this file contains all the variable which will be a part of playbook and imported as include_vars under task section.
azure_vars.yml
---
azure_nprod_vnet: "/subscriptions/XXXXXXXX-XXX-XXXX-XXXX-XXXXXXXXXXXX/resourceGroups/rg001/providers/Microsoft.Network/virtualNetworks/vnet"
azure_prod02_vnet: "/subscriptions/XXXXXXXX-XXX-XXXX-XXXX-XXXXXXXXXXXX/resourceGroups/rg003/providers/Microsoft.Network/virtualNetworks/vnet"
azure_prod03_vnet: "/subscriptions/XXXXXXXX-XXX-XXXX-XXXX-XXXXXXXXXXXX/resourceGroups/rg002/providers/Microsoft.Network/virtualNetworks/vnet"
# Azure domain
azure_domains:
- us-sea01
- us-azrc2
- eu-azrc1
# Resource group
azure_res_group:
- rg001
- rg002
- rg003
# Azure locations
azure_location:
- westus2
- southcentralus
- westeurope
Expected would be to club below three into one condition:
- set_fact:
location: "{{ azure_location[0] }}"
when: 'domain == azure_domain[0]'
- set_fact:
location: "{{ azure_location[1] }}"
when: 'domain == azure_domain[1]'
- set_fact:
location: "{{ azure_location[2] }}"
when: 'domain == azure_domain[2]'
May be something like:
- set_fact:
location:
- azure_location[0]
- azure_location[1]
- azure_location[2]
when:
- 'domain == azure_domain[0]
- 'domain == azure_domain[1]
- 'domain == azure_domain[2]

Answer 1

You can solve this using a loop and zip filter, or in the older fashion way, with a with_together — not recommended anymore, if you want to future-proof your playbooks.
Given the playbook:
- hosts: all
vars:
azure_vm_name: foo.bar.us-sea01.whatever.example.org
tasks:
- include_vars: azure_vars.yml
- set_fact:
host: "{{ azure_vm_name.split('.') }}"
- set_fact:
domain: "{{ host.2 }}"
- name: Domain
debug:
msg: "{{ domain }}"
- set_fact:
location: "{{ item.1 }}"
loop: "{{ azure_domains | zip(azure_location) | list }}"
when: 'domain == item.0'
- name: Location
debug:
msg: "{{ location }}"
And the variable file azure_vars.yml:
azure_domains:
- us-sea01
- us-azrc2
- eu-azrc1
azure_location:
- westus2
- southcentralus
- westeurope
This yields the recap:
PLAY [all] *******************************************************************************************************
TASK [Gathering Facts] *******************************************************************************************
ok: [localhost]
TASK [include_vars] **********************************************************************************************
ok: [localhost]
TASK [set_fact] **************************************************************************************************
ok: [localhost]
TASK [set_fact] **************************************************************************************************
ok: [localhost]
TASK [Domain] ****************************************************************************************************
ok: [localhost] => {
"msg": "us-sea01"
}
TASK [set_fact] **************************************************************************************************
ok: [localhost] => (item=['us-sea01', 'westus2'])
skipping: [localhost] => (item=['us-azrc2', 'southcentralus'])
skipping: [localhost] => (item=['eu-azrc1', 'westeurope'])
TASK [Location] **************************************************************************************************
ok: [localhost] => {
"msg": "westus2"
}
PLAY RECAP *******************************************************************************************************
localhost : ok=7 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
This said there is another possibility, using Python's capacities of Ansible. You could use the index() method of a list to target the element of azure_location being at the same position as domain in azure_domains.
e.g. if the domain is at position 2 of azure_domains, you'll get the element of position 2 in azure_location.
Given the playbook:
- hosts: all
vars:
azure_vm_name: foo.bar.us-sea01.whatever.example.org
tasks:
- include_vars: azure_vars.yml
- set_fact:
host: "{{ azure_vm_name.split('.') }}"
- set_fact:
domain: "{{ host.2 }}"
- name: Domain
debug:
msg: "{{ domain }}"
- set_fact:
location: "{{ azure_location[azure_domains.index(domain)] }}"
- name: Location
debug:
msg: "{{ location }}"
And the same variable file azure_vars.yml, this yields the recap:
PLAY [all] ******************************************************************************************************************
TASK [Gathering Facts] ******************************************************************************************************
ok: [localhost]
TASK [include_vars] *********************************************************************************************************
ok: [localhost]
TASK [set_fact] *************************************************************************************************************
ok: [localhost]
TASK [set_fact] *************************************************************************************************************
ok: [localhost]
TASK [Domain] ***************************************************************************************************************
ok: [localhost] => {
"msg": "us-sea01"
}
TASK [set_fact] *************************************************************************************************************
ok: [localhost]
TASK [Location] *************************************************************************************************************
ok: [localhost] => {
"msg": "westus2"
}
PLAY RECAP ******************************************************************************************************************
localhost : ok=7 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
Which is not using a loop, so makes an easier recap.