[wip][CI] Automatically publish to AUR

.github/workflows/publish-rapidgzip.yml

@@ -2,11 +2,12 @@ name: Publish Rapidgzip to PyPI
 
 on:
   push:
-    tags:
-      - 'rapidgzip-v*.*.*'
+    branches:
+      - 'oldmaster'
 
 jobs:
   Deploy-Wheels:
+    if: false
     runs-on: ${{ matrix.os }}
 
     strategy:
@@ -194,3 +195,56 @@ jobs:
         python3 -m build -o . --sdist ..
         mv rapidgzip-*.tar* src.tar
         conda build --token "$ANACONDA_TOKEN" .
+
+  Deploy-AUR:
+    runs-on: ubuntu-latest
+    container:
+      image: archlinux
+    steps:
+    - name: Set Up Non-Root User  # Because makepkg is an ass and forbids root from using it
+      run: |
+        groupadd sudo
+        useradd -m -G sudo user
+        echo '%sudo   ALL=(ALL:ALL) NOPASSWD: ALL' >> /etc/sudoers
+
+    - name: Install System Dependencies
+      run: |
+        pacman -Syu --noconfirm
+        pacman -Sy --noconfirm base-devel git python python-pip python-setuptools rhash openssh
+
+    - name: Clone Repository
+      env:
+        RAPIDGZIP_AUR_SSH: ${{ secrets.RAPIDGZIP_AUR_SSH }}
+      run: |
+        chmod a+rwx .
+        chown user .
+        su user -c 'mkdir -p "$HOME/.ssh/"'
+        su user -c 'echo "$RAPIDGZIP_AUR_SSH" > "$HOME/.ssh/id_ed25519"'
+        su user -c 'git clone ssh://[email protected]/python-rapidgzip.git .'
+        # For testing whether the update script works
+        su user -c 'git checkout HEAD~'
+
+    - name: Update PKGBUILD
+      run: |
+        # Annoyingly, --no-deps is not sufficient and building the wheels would still be triggered even
+        # just for downloading the source tarball! But, --no-build-isolation seems to avoid that:
+        # https://discuss.python.org/t/pip-download-just-the-source-packages-no-building-no-metadata-etc/4651/7
+        pip download --no-binary :all: --no-deps --no-build-isolation rapidgzip
+        pkgver=$( echo rapidgzip-*.tar.gz | sed -E 's|rapidgzip-([0-9.]*).*[.]tar.gz|\1|' )
+        blake2b=$( python3 -c 'import hashlib, sys; h=hashlib.blake2b(digest_size=256 // 8); h.update(open(sys.argv[1], "rb").read()); print(h.digest().hex())' rapidgzip-*.tar.gz )
+        # Update PKGBUILD
+        sed -i "s|pkgver=.*|pkgver=$pkgver|" PKGBUILD
+        sed -i "s|sha256sums=.*|sha256sums=(\"$( rhash -p"%x{sha-256}" rapidgzip-*.tar.gz )\")|" PKGBUILD
+        sed -i -E "s|(.*pythonhosted.org/packages)/[0-9a-f]{2}/[0-9a-f]{2}/[0-9a-f]*/(.*)|\1/${blake2b:0:2}/${blake2b:2:2}/${blake2b:4}/\2|" PKGBUILD
+        su user -c 'makepkg --printsrcinfo > .SRCINFO'
+        su user -c 'git add -f PKGBUILD .SRCINFO'
+        su user -c 'git config --local user.email "[email protected]"'
+        su user -c 'git config --local user.name "Maximilian Knespel"'
+        su user -c "git commit -m 'Update to $pkgver'"
+        su user -c 'git status'
+        su user -c 'git show'
+
+    - name: Test PKGBUILD
+      run: |
+        su user -c 'makepkg -s --noconfirm'
+        su user -c 'makepkg --noconfirm --install python-rapidgzip-*.tar.zst'