Is there a way to extend multiple templates with resources in Azure DevOps?

Question

I have one pipeline that is referencing several templates with resources and I know you can extend a template with resources by using the extend keyword. I've been looking at this documentation trying to make it work.

azure-pipeline.yaml

trigger: none

resources:
  repositories:
    - repository: repoName
      type: git
      name: project/repoName
    - repository: 'Release Notes'
      name: 'project/Release Notes'
      type: git
  pipelines:
    - pipeline: ooi-adf-ci
      source: ooi-adf-ci

extends:
  - {template: '/cicd/pipelines/templates/stages-deploy-app-registration.yaml'}
  - {template: '/cicd/pipelines/templates/stages-set-app-credentials.yaml'}
  - {template: '/cicd/pipelines/templates/stages-buying-release-apps.yaml'}
  - {template: '/cicd/pipelines/templates/stages-buying-adf.yaml'}

I also tried something like:

extends:
  template:
    [
      '/cicd/pipelines/templates/stages-deploy-app-registration.yaml',
      '/cicd/pipelines/templates/stages-set-app-credentials.yaml',
      '/cicd/pipelines/templates/stages-buying-release-apps.yaml',
      '/cicd/pipelines/templates/stages-buying-adf.yaml',
    ]

template.yaml where the resource is consumed:

...
resources:
  pipelines:
    - pipeline: ooi-adf-ci
      source: ooi-adf-ci
...

I get an error in my azure-pipeline.yaml file saying "A sequence was not expected". I'm wondering if this is actually possible as I haven't been able to find any documentation on it or if I'm just incorrectly doing it.

Answer 1

I dont think you can infinitely extend templates at the root level, as in your example.

What you can do is compose a azure-pipeline.yaml file where each job / step is from a template. I do this a lot and works perfectly.

Here is the official docs: enter link description here