Image Resizer Action

A fast, Rust-powered GitHub Action to batch-resize images by width while preserving aspect ratio.

🎨 Example Output

From left to right: the original image (1024 px) is resized down to 256 px, 128 px, and 64 px.

📦 Usage

In your workflow, reference this action and supply the folder of source images, desired widths, and an output folder:

📖 Example Workflow

name: Resize App Images

on:
  push:
    branches: [master] # Trigger on pushes to master branch
  workflow_dispatch: # Allow manual runs from the Actions tab

# Grant write permission so the workflow can commit back to the repo
permissions:
  contents: write

jobs:
  resize:
    runs-on: ubuntu-latest

    steps:
      # 1. Checkout the repo so we can read/write files
      - name: Check out code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.GITHUB_TOKEN }} # Provides auth for checkout & push
          persist-credentials: true # Keep token in Git config for commits

      # 2. Configure a Git user so commits have a valid author
      - name: Configure Git user
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      # 3. Run the custom resize action
      - name: Resize images
        uses: elarsaks/resize-rs@v0.1.1
        with:
          source-dir: assets/original # Source directory of original images
          sizes: "64,128,256" # Target resize dimensions
          output-dir: assets/resized # Where resized images are saved

      # 4. Commit & push only if new/resized files exist
      - name: Commit & push resized files
        run: |
          git add assets/resized
          git diff --cached --quiet || (      # Check for staged changes
            git commit -m "ci: add resized images"
            git push                         # Push commits to the triggering branch
          )

🔧 Inputs

Input	Description	Required	Default
source-dir	Directory containing original images	true	—
sizes	Comma-separated list of target widths (px)	true	—
output-dir	Directory where resized images will be saved	true	—

🛠️ Outputs

It writes resized files into output-dir.

📄 License

MIT © Elar Saks