Azure devops: pass variable group as parameter to Template - templates

Question

I am using Azure devops yml pipeline at code base.
I have created Variable Group at pipeline (pipeline > Library > variable group > called 'MY_VG')
In my pipeline (yml) file i want to send this variable group MY_VG to template my_template.yml as parameter.
But this parameter MY_VG is not being expanded when i use it under 'Variable' (though while printing it gives me value)
How to access the value of this MY_VG in the template here group: ${{parameters.variable_group}} shown below?
(I am calling a template file my_template_iterator.yml which iterates the environments and call the my_template.yml)
azure-pipelines.yml
resources:
repositories:
- repository: templates
type: git
name: MY_PROJECT/GIT_REPO_FOR_TEMPLATE
stages:
- stage: "CheckOut"
displayName: Checkout
jobs:
- job: Checkout
displayName: Checkout Application
pool:
name: $(my_pool_name)
workspace:
clean: all
steps:
- checkout: self
- template: folder_name/my_template_iterator.yml#templates
parameters:
agent_pool_name: $(my_pool)
db_resource_path: $(System.DefaultWorkingDirectory)/src/main/resources/db
envs:
- env:
env_name: 'dev'
variable_group: MY_VG
pipeline_environment_name: DEV_ENV
is_master: and(succeeded(), eq(variables['Build.SourceBranch'], 'refs/heads/master'))
## Iterator: my_template_iterator.yml
parameters:
agent_pool_name: ''
db_resource_path: ''
envs: {}
stages:
- ${{ each env in parameters.envs }}:
- template: my_template.yml
parameters:
agent_pool_name: ${{ parameters.agent_pool_name }}
db_resource_path: ${{ parameters.db_resource_path }}
env_name: ${{ env.env_name }}
variable_group: ${{ env.variable_group }}
pipeline_environment_name: ${{ env.pipeline_environment_name }}
is_master: ${{ env.is_master }}
## my_template.yml
parameters:
- name: 'variable_group'
type: string
default: 'default_variable_group'
stages:
- stage:
displayName: Read Parameters
jobs:
- job: READ
displayName: Reading Parameters
steps:
- script: |
echo variable_group: ${{parameters.variable_group}}
- stage:
displayName: Deployment
variables:
group: ${{parameters.variable_group}}
condition: ${{parameters.is_master}}

Answer 1

I tested with above your yaml files. It seems fine. However i found a small mistake that you missed a - when you define a variable group in my_template.yml of yours. Maybe that is the reason the variable group didnot expand for you.
variables:
# a variable group
- group: myvariablegroup
I modified your my_template.yml file a little bit. And i got it working. See below:
parameters:
- name: 'variable_group'
type: string
default: 'default_variable_group'
- name: agent_pool_name
default: ""
- name: env_name
default: ""
- name: db_resource_path
default: ""
- name: pipeline_environment_name
default: ""
- name: is_master
default: ""
stages:
- stage:
displayName: ${{parameters.env_name}}
## i changed here add '-' to group
variables:
- group: ${{parameters.variable_group}}
jobs:
- job: READ
displayName: Reading Parameters
steps:
- script: |
echo variable_group: ${{parameters.variable_group}}
- powershell: echo "$(variableName-in-variablegroup)"

Answer 2

Ok. I'm not sure if this doable in a way how you are trying. But I tried another approach which seems to be working.
First let's define template for simple stage:
parameters:
- name: env_name
type: string
default: 'dev'
- name: variable_group
type: string
default: 'MY_VG'
- name: pipeline_environment_name
type: string
default: 'DEV_ENV'
stages:
- stage: ${{ parameters.env_name }}
jobs:
- job: angularinstall
steps:
- script: echo "${{ parameters.env_name }}"
- script: echo "${{ parameters.variable_group }}"
- script: echo "${{ parameters.pipeline_environment_name }}"
then template for main build:
parameters:
- name: stages # the name of the parameter is stageList
type: stageList # data type is stageList
default: [] # default value of stageList
stages: ${{ parameters.stages }}
and then we can combine them together in main build file:
extends:
template: template.yaml
parameters:
stages:
- template: stageTemplate.yaml
parameters:
env_name: 'dev'
variable_group: 'MY_VG'
pipeline_environment_name: 'DEV_ENV'
- template: stageTemplate.yaml
parameters:
env_name: 'stage'
variable_group: 'MY_STAGE'
pipeline_environment_name: 'STAGE_ENV'
And for that I got:
Does it sth what bring you closer to your solution?