Add discover

.gitea/workflows/nightly.yml

@@ -16,12 +16,47 @@ on:
         default: "false"
 
 jobs:
-  build:
+  discover:
     runs-on: ubuntu-latest
+    container:
+      image: archlinux:latest
+    outputs:
+      packages: ${{ steps.list.outputs.packages }}
+    steps:
+      - name: Install toolchain
+        run: |
+          # nodejs is required by JS actions like actions/checkout.
+          pacman -Syu --noconfirm --needed git python nodejs
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: List packages
+        id: list
+        env:
+          ONLY: ${{ github.event.inputs.only }}
+        run: |
+          packages=$(python3 autopackage.py --list-json ${ONLY:+--only $ONLY})
+          echo "packages=$packages" >> "$GITHUB_OUTPUT"
+          echo "Matrix: $packages"
+
+  build:
+    needs: discover
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
     container:
       image: archlinux:latest
       # makepkg refuses to run as root; we create a build user below.
       options: --privileged
+    strategy:
+      # Build every package even if one fails.
+      fail-fast: false
+      # Tune to your runner capacity; remove for unlimited parallelism.
+      max-parallel: 3
+      matrix:
+        pkg: ${{ fromJSON(needs.discover.outputs.packages) }}
     steps:
       - name: Install toolchain
         run: |
@@ -48,8 +83,8 @@ jobs:
           AUTOPKG_USER: ${{ github.actor }}
           AUTOPKG_TOKEN: ${{ secrets.PACKAGE_TOKEN || github.token }}
           AUTOPKG_REPLACE: ${{ github.event.inputs.replace }}
-          ONLY: ${{ github.event.inputs.only }}
+          PKG: ${{ matrix.pkg }}
         run: |
           # -E keeps AUTOPKG_*; force HOME to builder's so cargo/git/etc. can write their caches
           sudo -E -u builder env HOME=/home/builder \
-            python3 autopackage.py --keep-going ${ONLY:+--only $ONLY}
+            python3 autopackage.py --only "$PKG"