Fetch particular git hash remotely in pi-gen releases

build-docker.sh

@@ -30,6 +30,8 @@ do
 	esac
 done
 
+PI_GEN_REPO=${PI_GEN_REPO:-https://github.com/RPi-Distro/pi-gen}
+
 # Ensure that the configuration file is an absolute path
 if test -x /usr/bin/realpath; then
 	CONFIG_FILE=$(realpath -s "$CONFIG_FILE" || realpath "$CONFIG_FILE")
@@ -55,7 +57,11 @@ exit 1
 fi
 
 # Ensure the Git Hash is recorded before entering the docker container
-GIT_HASH=${GIT_HASH:-"$(git rev-parse HEAD)"}
+if [ -d "${DIR}"/.git ]; then
+    GIT_HASH=${GIT_HASH:-$(git rev-parse HEAD)}
+else
+    GIT_HASH=$(git ls-remote --tags "${PI_GEN_REPO}" | grep $(basename "${DIR}" | cut -d'-' -f3-) | awk '{print $1}')
+fi
 
 CONTAINER_EXISTS=$(${DOCKER} ps -a --filter name="${CONTAINER_NAME}" -q)
 CONTAINER_RUNNING=$(${DOCKER} ps --filter name="${CONTAINER_NAME}" -q)

build.sh

@@ -179,7 +179,13 @@ export KEYBOARD_LAYOUT="${KEYBOARD_LAYOUT:-English (UK)}"
 
 export TIMEZONE_DEFAULT="${TIMEZONE_DEFAULT:-Europe/London}"
 
-export GIT_HASH=${GIT_HASH:-"$(git rev-parse HEAD)"}
+if [ -z "${GIT_HASH}" ]; then
+    if [ -d "${BASE_DIR}"/.git ]; then
+        export GIT_HASH=${GIT_HASH:-$(git rev-parse HEAD)}
+    else
+        export GIT_HASH=$(git ls-remote --tags "${PI_GEN_REPO}" | grep $(basename "${BASE_DIR}" | cut -d'-' -f3-) | awk '{print $1}')
+    fi
+fi
 
 export CLEAN
 export IMG_NAME