How to run a script from file in another project using include in GitLab CI?

I'm trying to run a shell script from my template file located in another project via my include.

How should this be configured to work? Below scripts are simplified versions of my code.

Project A

template.yml

deploy:
  before_script:
    - chmod +x ./.run.sh
    - source ./.run.sh

Project B

gitlab-ci.yml

include:
 - project: 'project-a'
    ref: master
    file: '/template.yml'

stages:
  - deploy

Clearly, the commands are actually being run from ProjectB and not ProjectA where the template resides. This can further be confirmed by adding ls -a in the template file.

So how should we be calling run.sh? Both projects are on the same GitLab instance under different groups.

Solution

If you have access project A and B, you can use multi-project pipelines. You trigger a pipeline in project A from project B.

In project A, you clone project B and run your script.

Project B

job 1:
  variables:
    PROJECT_PATH: "$CI_PROJECT_PATH"
    RELEASE_BRANCH: "$CI_COMMIT_BRANCH"
  trigger:
    project: project-a
    strategy: depend

Project A

job 2:
  rules:
    - if: '$CI_PIPELINE_SOURCE == "pipeline" && $PROJECT_PATH && $RELEASE_BRANCH'
  script:
    - git clone -b "${RELEASE_BRANCH}" --depth 50 https://gitlab-ci-token:${CI_JOB_TOKEN}@${CI_SERVER_HOST}/${PROJECT_PATH}.git $(basename ${PROJECT_PATH})
    - cd $(basename ${PROJECT_PATH})
    - chmod +x ../.run.sh
    - source ../.run.sh