Azure Devops Return Variable from Template - azure-devops

Question

Is there a way to return a variable from a template so I can use that as a parameter for other templates?
I have a yml file that looks something like this (actual names redacted).
- stage: A
jobs:
- template: a.yml
parameters:
environment: foo
group: bar
- template: b.yml
parameters:
dependsOn: a
environment: foo
group: bar
- template: c.yml
parameters:
dependsOn: a
environment: foo
group: bar
Each template is a deployment.
I want a.yml to set a variable, then for that to be returned so that I could use that variable as a parameter for the other 2 templates. How can I return a variable using 'a.yml'?

Answer 1

You can use depands to pass parameters between two templates just as passing parameters between stages. Here is an example. I use environment as the parameters to be passed between a.yml and b.yml.
a.yml:
parameters:
environment: foo
group: bar
jobs:
- job: deployA
variables:
env: ${{ parameters.environment }}
steps:
- pwsh: |
echo "##vso[task.setvariable variable=env;isOutput=true]$($env:ENV)"
name: outputVar
b.yml:
parameters:
dependsOn: a
environment: foo
group: bar
jobs:
- job: deployB
dependsOn: deployA
steps:
...
pipeline.yml:
trigger: none
pool:
vmImage: ubuntu-latest
stages:
- stage: A
jobs:
- template: a.yml
parameters:
environment: Test
- template: templateB.yml
parameters:
environment: $[dependencies.deployA.outputs['outputVar.env']]