How can I access GitHub Action environment variables within a Bash script run by the Action?

Question

I'm not able to access environment variables defined at the top-level of a GitHub Action configuration file from within a script run by the action.

For example, given the following config file:

name: x-pull-request
on: pull_request
env:
  FOO: bar
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v1
      - name: does a thing
        run: ./scripts/do-a-thing.sh

... and the following script:

X=${FOO:default}
echo "X: $X" # X: default

The FOO environment variable defined in the config file is not available to the script and the default value is being used.

So, how can I access the environment variable from a Bash script run by the build step? Am I missing a prefix or something? (I know values defined in the input hash require you to use an INPUT_ prefix when referencing them.)

Answer 1

You can use env at any level, since the root action, also in job and step.

I wrote a test action and a test script to validate it. Take a look.

The action file:

name: Env tests
on: push

env:
  FOO_ROOT: bar on root

jobs:
  test:
    runs-on: ubuntu-latest
    env:
      FOO_JOB: bar on job
    steps:
      - uses: actions/checkout@v1
      - name: Test envs
        run: ./env-test.sh
        env:
          FOO_STEP: bar on step

The script file:

#!/usr/bin/env bash

echo "FOO_ROOT: $FOO_ROOT"
echo "FOO_JOB: $FOO_JOB"
echo "FOO_STEP: $FOO_STEP"
echo " "
printenv

The results:

FOO_ROOT: bar on root
FOO_JOB: bar on job
FOO_STEP: bar on step

LEIN_HOME=/usr/local/lib/lein
M2_HOME=/usr/share/apache-maven-3.6.3
...

Check mine results here.

In fact, I don't know why it didn't work on you side, because, it must work.

Answer 2

If some one else is searching for a solution:

You have to explicity pass the environment variables to the bash script. Otherwise they are not available.

name: x-pull-request
on: pull_request
env:
  FOO: bar
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v1
      - name: does a thing
        run: ./scripts/do-a-thing.sh $FOO

And in the Script you have to map the parameter to a variable.

X=$1
echo "X: $X" # X: default

Hope this helps.