copy recordbox message (DeliveryComment) from rekordbox db to mp3 id3 tag on the track file

sync_rekordbox_messages.py

#!/usr/bin/env python3
"""
Sync Rekordbox 'Message' field to ID3 comments.

Reads all tracks from the Rekordbox 6 database that have a DeliveryComment
(displayed as 'Message' in Rekordbox UI) and writes the value to the
standard ID3 COMM frame.
"""

import sys
from pathlib import Path

from mutagen.id3 import ID3, COMM, ID3NoHeaderError
from mutagen.mp3 import MP3
from pyrekordbox import Rekordbox6Database


def sync_messages(dry_run: bool = False):
    """Sync Rekordbox Message fields to ID3 comments."""
    print("Opening Rekordbox database...")
    db = Rekordbox6Database()

    tracks = db.get_content()
    updated = 0
    skipped = 0
    errors = 0

    for track in tracks:
        message = track.DeliveryComment
        if not message:
            continue

        file_path = Path(track.FolderPath)

        if not file_path.exists():
            print(f"  [SKIP] File not found: {file_path}")
            skipped += 1
            continue

        if file_path.suffix.lower() != ".mp3":
            print(f"  [SKIP] Not an MP3: {file_path}")
            skipped += 1
            continue

        try:
            # Load or create ID3 tags
            try:
                tags = ID3(file_path)
            except ID3NoHeaderError:
                tags = ID3()

            # Check existing comment
            existing_comment = None
            for key in tags.keys():
                if key.startswith("COMM"):
                    existing_comment = str(tags[key])
                    break

            if existing_comment == message:
                print(f"  [OK] Already set: {track.Title} - {track.ArtistName}")
                continue

            if dry_run:
                print(f"  [DRY-RUN] Would update: {track.Title} - {track.ArtistName}")
                print(f"            Message: {message}")
                if existing_comment:
                    print(f"            (Existing comment: {existing_comment})")
                updated += 1
                continue

            # Add/update COMM frame
            tags.delall("COMM")
            tags.add(COMM(
                encoding=3,  # UTF-8
                lang="eng",
                desc="",
                text=message
            ))
            tags.save(file_path)

            print(f"  [UPDATED] {track.Title} - {track.ArtistName}: {message}")
            updated += 1

        except Exception as e:
            print(f"  [ERROR] {file_path}: {e}")
            errors += 1

    db.close()

    print()
    print(f"Summary: {updated} updated, {skipped} skipped, {errors} errors")


if __name__ == "__main__":
    dry_run = "--dry-run" in sys.argv or "-n" in sys.argv

    if dry_run:
        print("=== DRY RUN MODE (no changes will be made) ===")
        print()

    sync_messages(dry_run=dry_run)