Executing Shell Scripts in Workflow

Running multiple commands as separate run steps can clutter your GitHub Actions workflow. By bundling them into a single shell script, you simplify maintenance, improve readability, and reduce duplication.

1. Why Consolidate `run` Steps?

When you split each command into its own run, your workflow becomes long and harder to manage:

jobs:
  ascii_job:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Repo
        uses: actions/checkout@v4

      - name: Install Cowsay
        run: sudo apt-get install cowsay -y

      - name: Generate ASCII Art
        run: cowsay -f dragon "Run for cover; I am a DRAGON... RAWR!" >> dragon.txt

      - name: Search for "dragon"
        run: grep -i "dragon" dragon.txt

      - name: Display File Contents
        run: cat dragon.txt

      - name: List Repo Files
        run: ls -ltra

Approach	Pros	Cons
Multiple `run` steps	Easy to read individual steps	Repetitive YAML; longer file
Single shell script call	Cleaner workflow; reusability	Must manage external script

2. Create a Reusable Shell Script

Add a file named ascii-script.sh at the root of your repository with all commands:

#!/bin/sh
sudo apt-get update
sudo apt-get install cowsay -y
cowsay -f dragon "Run for cover; I am a DRAGON... RAWR!" >> dragon.txt
grep -i "dragon" dragon.txt
cat dragon.txt
ls -ltra

Make sure to commit this script:

git add ascii-script.sh
git commit -m "Add ASCII art shell script"

Note

You can reference this pattern for any multi-step process—testing, building, or deployment—by swapping commands in your script.

3. Refactor Your Workflow to Invoke the Script

Update your workflow to run only the script:

jobs:
  ascii_job:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4

      - name: List Current Files
        run: ls -ltra

      - name: Run ASCII Art Script
        run: ./ascii-script.sh

After pushing, navigate to the Actions tab to see your new workflow run:

The image shows a GitHub Actions page with a list of workflow runs, displaying their status, branch, and timestamps. Some workflows are marked as successful, while others have failed or are in progress.

4. Troubleshoot “Permission denied”

If you see an exit code 126, it means the script lacks execute permissions:

The image shows a GitHub Actions page where a workflow named "Executing Shell Script" has failed. The job "ascii_job" completed with an exit code 126.

/home/runner/work/_temp/.../script.sh: line 1: ./ascii-script.sh: Permission denied
Error: Process completed with exit code 126

Warning

Always ensure your script is executable. You can either set the permission locally with chmod +x ascii-script.sh before committing, or update your workflow to grant permissions at runtime.

5. Grant Execute Permissions in the Workflow

Modify the step to add execution rights before running the script:

jobs:
  ascii_job:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4

      - name: List Current Files
        run: ls -ltra

      - name: Run ASCII Art Script
        run: |
          chmod +x ascii-script.sh
          ./ascii-script.sh

Commit and push these changes to restart the workflow.

6. Verify the Successful Run

When the workflow reruns, you’ll see:

Run ls -ltra
total 24
-rw-r--r-- 1 runner docker 161 Oct 11 11:17 ascii-script.sh
-rw-r--r-- 1 runner docker 227 Oct 11 11:17 README.md
...

And then:

chmod +x ascii-script.sh
./ascii-script.sh
shell: /usr/bin/bash -e {0}
# [sudo] password for runner: 
# Get:1 http://archive.ubuntu.com/ubuntu focal InRelease [265 kB]
# ...
# Code generated by Cowsay
dragon: I'm a DRAGON... RAWR!
# dragon.txt
...

Your script installs Cowsay, generates ASCII art, searches and displays content, and lists files—all in one step.

References

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