build: do not query GitHub API if origin is upstream

If the "origin" remote of the local repository is the upstream repo dtcooper/raspotify, do not query the GitHub API for upstream tags. It is supposed to have tags then, else the local repo is faulty.

Signed-off-by: MichaIng <micha@dietpi.com>

build.sh

@@ -160,12 +160,20 @@ cd /mnt/raspotify
 echo 'Obtaining latest Git repository tag for DEB package version ...'
 RASPOTIFY_GIT_VER="$(git describe --tags "$(git rev-list --tags --max-count=1)" || :)"
 if [ -z "$RASPOTIFY_GIT_VER" ]; then
-	echo 'Could not obtain latest tag from local repository. Obtaining it from upstream: https://api.github.com/repos/dtcooper/raspotify/tags'
-	RASPOTIFY_GIT_VER="$(curl -sSf  "https://api.github.com/repos/dtcooper/raspotify/tags" | awk -F\" '/^ *"name": "/{print $4;exit}' || :)"
-fi
-if [ -z "$RASPOTIFY_GIT_VER" ]; then
-	echo 'Could not obtain latest tag from upstream repository either. Exiting ...'
-	exit 1
+	# Derive from origin URL whether this is dtcooper/raspotify and hence supposed to have tags.
+	# If so, exit right here, else get tags from dtcooper/raspotify via GitHub API, since forks often do not have any tags.
+	url="$(git remote get-url origin || :)"
+	if [ "$url" = 'https://github.com/dtcooper/raspotify' ] || [ "$url" = 'https://github.com/dtcooper/raspotify/' ] || [ "$url" = 'https://github.com/dtcooper/raspotify.git' ]; then
+		echo 'E: Could not obtain any tag. Exiting ...'
+		exit 1
+	else
+		echo 'W: Could not obtain latest tag from local repository. Obtaining it from upstream: https://api.github.com/repos/dtcooper/raspotify/tags'
+		RASPOTIFY_GIT_VER="$(curl -sSf  "https://api.github.com/repos/dtcooper/raspotify/tags" | awk -F\" '/^ *"name": "/{print $4;exit}' || :)"
+		if [ -z "$RASPOTIFY_GIT_VER" ]; then
+			echo 'E: Could not obtain latest tag from upstream repository either. Exiting ...'
+			exit 1
+		fi
+	fi
 fi
 RASPOTIFY_HASH="$(git rev-parse HEAD | cut -c 1-7 || echo unknown)"