added mp3_set_artist.sh

mp3_set_artist.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+#  vim:ts=4:sts=4:sw=4:et
+#
+#  Author: Hari Sekhon
+#  Date: 2020-07-21 11:36:49 +0100 (Tue, 21 Jul 2020)
+#
+#  https://github.com/harisekhon/bash-tools
+#
+#  License: see accompanying Hari Sekhon LICENSE file
+#
+#  If you're using my code you're welcome to connect with me on LinkedIn and optionally send me feedback to help steer this or other code I publish
+#
+#  https://www.linkedin.com/in/harisekhon
+#
+
+set -euo pipefail
+[ -n "${DEBUG:-}" ] && set -x
+srcdir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# shellcheck disable=SC2034
+usage_description="
+Adds / Modifies artist metadata across all mp3 files in the given directories to edit albums or group audiobooks for Mac's Books.app
+
+Shows the list of MP3 files that would be affected before running the metadata update and prompts for confirmation before proceeding for safety
+"
+
+# used by usage() in lib/utils.sh
+# shellcheck disable=SC2034
+usage_args="\"artist name\" <dir1> [<dir2> ...]"
+
+# shellcheck disable=SC1090
+. "$srcdir/lib/utils.sh"
+
+help_usage "$@"
+
+min_args 2 "$@"
+
+check_bin id3v2
+
+artist="$1"
+
+shift || :
+
+mp3_files="$(for dir in "$@"; do find "$dir" -maxdepth 2 -iname '*.mp3' || exit 1; done)"
+
+echo "List of MP3 files to set artist = '$artist':"
+echo
+echo "$mp3_files"
+echo
+read -r -p "Are you happy to set the artist metadata on all of the following mp3 files to '$*' (y/N) " answer
+
+if [ "$answer" != "y" ]; then
+    echo "Aborting..."
+    exit 1
+fi
+
+echo
+
+while read -r mp3; do
+    echo "setting artist '$artist' on '$mp3'"
+    id3v2 --artist "$artist" "$mp3"
+done <<< "$mp3_files"