Add workflow for uploading lab archives

.github/workflows/lab-archive.yml

@@ -0,0 +1,60 @@
+name: Archive Labs on Commit
+
+on:
+  push:
+    branches:
+      - 'main'
+
+permissions:
+  contents: write
+
+jobs:
+  archive-labs:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.x'
+
+      - name: Install dependencies
+        run: pip install pyyaml
+
+      - name: Run archive script
+        run: python3 gen-zip.py config.yaml
+
+      - name: Push archives to lab-archives branch
+        if: success()
+        run: |
+          if [ -z "$(ls -A *.zip 2>/dev/null)" ]; then
+            echo "No archives generated — nothing to push."
+            exit 0
+          fi
+
+          # Create or switch to lab-archives branch
+          if git ls-remote --exit-code origin lab-archives; then
+            git fetch origin lab-archives
+            git checkout lab-archives
+          else
+            git checkout --orphan lab-archives
+            git rm -rf .
+          fi
+
+          # Copy new zips into branch root
+          git add *.zip
+
+          # Only commit if there are changes
+          if ! git diff --cached --quiet; then
+            git config user.name "github-actions[bot]"
+            git config user.email "github-actions[bot]@users.noreply.github.com"
+            git commit -m "Update lab archives for commit $GITHUB_SHA"
+            git push origin lab-archives
+          else
+            echo "No changes to commit."
+          fi

gen-zip.py

@@ -0,0 +1,118 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: BSD-3-Clause
+
+import yaml
+import sys
+import re
+import subprocess
+import os
+import zipfile
+from pathlib import Path
+
+
+def load_yaml(yaml_path):
+    with open(yaml_path, "r") as f:
+        return yaml.safe_load(f)
+
+
+def extract_task_info_by_lab(data):
+    """
+    Return a dict:
+    lab_title -> {
+      'tasks': [ 'tasks/memory-access.md', ... ],
+      'basenames': [ 'memory-access.md', ... ],
+      'stems': [ 'memory-access', ... ]
+    }
+    """
+    labs = data.get("lab_structure", [])
+    lab_info = {}
+
+    for lab in labs:
+        title = lab.get("title", "Untitled Lab")
+        content = lab.get("content", [])
+        task_files = [c for c in content if c.startswith("tasks/")]
+        basenames = [Path(t).name for t in task_files]
+        stems = [Path(t).stem for t in task_files]
+
+        lab_info[title] = {"tasks": task_files, "basenames": basenames, "stems": stems}
+
+    return lab_info
+
+
+def get_changed_files_last_commit():
+    """Return a list of file paths changed in the last commit."""
+    cmd = ["git", "diff", "--name-only", "HEAD~1", "HEAD"]
+    result = subprocess.run(cmd, capture_output=True, text=True, check=True)
+    return [line.strip() for line in result.stdout.splitlines() if line.strip()]
+
+
+def find_directories_by_name(dirname):
+    """
+    Return a list of directories in the repo that match the given base name.
+    Example: dirname='memory-access' matches any '.../memory-access' dir.
+    """
+    matches = []
+    for root, dirs, _ in os.walk("."):
+        for d in dirs:
+            if d == dirname:
+                matches.append(os.path.join(root, d))
+    return matches
+
+
+def create_zip_archive(lab_title, directories):
+    """
+    Create a zip archive named after the lab title containing all directories.
+    """
+    safe_name = re.sub(r"[^a-zA-Z0-9_]+", "_", lab_title)
+    zip_filename = f"{safe_name}.zip"
+
+    with zipfile.ZipFile(zip_filename, "w", zipfile.ZIP_DEFLATED) as zipf:
+        for d in directories:
+            for folder, _, files in os.walk(d):
+                for file in files:
+                    file_path = os.path.join(folder, file)
+                    arcname = os.path.relpath(file_path, d)
+                    zipf.write(file_path, os.path.join(os.path.basename(d), arcname))
+
+    return zip_filename
+
+
+def main():
+    if len(sys.argv) != 2:
+        sys.exit(1)
+
+    yaml_path = sys.argv[1]
+
+    # 1. Parse YAML and extract task info
+    data = load_yaml(yaml_path)
+    lab_info = extract_task_info_by_lab(data)
+
+    # 2. Get changed files from last commit
+    changed_files = get_changed_files_last_commit()
+    changed_basenames = [Path(f).name for f in changed_files]
+
+    # 3. Identify labs to archive
+    for lab_title, info in lab_info.items():
+        # Check if any changed filename matches one of the task basenames
+        stems = info["stems"]
+        lab_changed = any(
+            any(stem.lower() in changed_path.lower() for stem in stems)
+            for changed_path in changed_files
+        )
+
+        if not lab_changed:
+            continue
+
+        # Collect all directories for all task stems in this lab
+        dirs_to_zip = []
+        for stem in info["stems"]:
+            found_dirs = find_directories_by_name(stem)
+            if found_dirs:
+                dirs_to_zip.extend(found_dirs)
+
+        if dirs_to_zip:
+            create_zip_archive(lab_title, dirs_to_zip)
+
+
+if __name__ == "__main__":
+    main()