Download CalyxOS boot.img for more convenient rooting

boot-img.sh

#!/usr/bin/env bash

set -o errexit -o nounset -o pipefail

# Download lastest Calyx factory image and extract boot.img to be patched via magisk
                                                     # See here for device names: https://calyxos.org/install/
DEVICE=oriole

CHANNEL=stable4
DEST_DIR=/storage/emulated/0/Download
VERSION=$(curl -s https://release.calyxinstitute.org/$DEVICE-$CHANNEL | cut -d ' ' -f1)
TMPDIR=$(mktemp -d)                                  
(
        cd $TMPDIR

        # See also updater app                               # https://gitlab.com/CalyxOS/platform_packages_apps_Updater/-/blob/android13/src/app/seamlessupdate/client/Service.java#L263
        curl -o release.zip https://release.calyxinstitute.org/oriole-factory-$VERSION.zip
        curl -o release.zip.minisig https://release.calyxinstitute.org/oriole-factory-$VERSION.zip.minisig        # Download the public key
        curl -o minisign.pub https://release.calyxinstitute.org/minisign.pub

        minisign -Vm release.zip -p minisign.pub     
        #unzip -l e.g.       967  2023-01-04 19:05   something/some.zip
        ZIP_PATH=$(unzip -l release.zip | grep .zip | awk '{print $4}')
        unzip -j release.zip $ZIP_PATH
        rm release.zip release.zip.minisig
        FINAL_ZIP=$(find . -iname '*.zip')           
        # Note that there is a vendor_boot.img
        BOOT_IMG_PATH=$(unzip -l $FINAL_ZIP | grep ' boot.img' | awk '{print $4}')

        unzip -j $FINAL_ZIP $BOOT_IMG_PATH          
)

mv $TMPDIR/boot.img $DEST_DIR/$DEVICE-$VERSION-boot.img
rm -rf $TMPDIR                                       
echo Wrote $DEST_DIR/$DEVICE-$VERSION-boot.img
                                                     # Patch img right away?
# https://github.com/affggh/Magisk_patcher/blob/ttkbootstrap/README_EN.md