Sorry if this is a stupid question, but I'm confused by this statement in the readme file:

the absolute path to the photos must remain the same. For example, if your photos were located on an external drive named "Fotos" and in a folder named "MyFotos" the path would /Volumes/Fotos/MyFotos, the new volume must also be named "Fotos" and the folder must be named "MyFotos".

But isn't the whole point of the script to solve the problem that

If you move the photos to a different volume or computer, even with the same name, Photos will be unable to open the original files and will produce a "Missing file" dialog.

So I must be misunderstanding something when I think: the problem is that Photos no longer sees my files because the path has changed but this can only be fixed if the files are in the same path...

Could you explain what I'm missing?

Thanks, @RhetTbull. No joy with that, unfortunately, but I've been able to run it fine on a non-M1 Mac.

Although I've since discovered it doesn't quite help for my use case. I have a Photos library that was originally an iPhoto library with half the photos were referenced and while I still have the folder of images, the link to them is now broken as they're no longer on the same volume. But it seems that this script reads and updates the ZBOOKMARKDATA blob and I was hoping it would be able to write missing ZBOOKMARKDATA blobs from the path data, as because this library came from iPhoto there is no existing ZBOOKMARKDATA data.

But don't worry, I'll explore further options. Thanks for your time on this script though!

Originally posted by @purplespider in https://github.com/RhetTbull/RepairPhotosBookmarks/issues/3#issuecomment-1140998968

Struggling to get past this error when running:

WARNING: this program will rewrite your Photos library database and could result in total data loss.
Please ensure you have a backup and that the Photos app is not running!
Do you want to proceed? [y/N]: y
Please open Photos and uncheck the box 'Importing: Copy items to the Photos library' in Photos Preferences.
Type 'y' when you have done this. [y/N]: y
Please quit Photos.
Type 'y' when you have done this. [y/N]: y
Traceback (most recent call last):
  File "/opt/homebrew/lib/python3.9/site-packages/psutil/_psosx.py", line 343, in wrapper
    return fun(self, *args, **kwargs)
  File "/opt/homebrew/lib/python3.9/site-packages/psutil/_psosx.py", line 401, in cmdline
    return cext.proc_cmdline(self.pid)
ProcessLookupError: [Errno 3] assume no such process (originated from sysctl(KERN_PROCARGS2) -> EINVAL)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/james/Downloads/RepairPhotosBookmarks-main/repair_photos_bookmarks.py", line 356, in <module>
    main()
  File "/opt/homebrew/lib/python3.9/site-packages/click/core.py", line 1130, in __call__
    return self.main(*args, **kwargs)
  File "/opt/homebrew/lib/python3.9/site-packages/click/core.py", line 1055, in main
    rv = self.invoke(ctx)
  File "/opt/homebrew/lib/python3.9/site-packages/click/core.py", line 1404, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/opt/homebrew/lib/python3.9/site-packages/click/core.py", line 760, in invoke
    return __callback(*args, **kwargs)
  File "/Users/james/Downloads/RepairPhotosBookmarks-main/repair_photos_bookmarks.py", line 249, in main
    while photos_is_running():
  File "/Users/james/Downloads/RepairPhotosBookmarks-main/repair_photos_bookmarks.py", line 46, in photos_is_running
    return any(p.name() == "Photos" for p in psutil.process_iter())
  File "/Users/james/Downloads/RepairPhotosBookmarks-main/repair_photos_bookmarks.py", line 46, in <genexpr>
    return any(p.name() == "Photos" for p in psutil.process_iter())
  File "/opt/homebrew/lib/python3.9/site-packages/psutil/__init__.py", line 628, in name
    cmdline = self.cmdline()
  File "/opt/homebrew/lib/python3.9/site-packages/psutil/__init__.py", line 681, in cmdline
    return self._proc.cmdline()
  File "/opt/homebrew/lib/python3.9/site-packages/psutil/_psosx.py", line 348, in wrapper
    raise NoSuchProcess(self.pid, self._name)
psutil.NoSuchProcess: process no longer exists (pid=27506)

I'm on an M1 Mac Studio. Any pointers appreciated.

Although the current implementation appears to work -- as in Photos is able to locate the photos after repairing bookmarks -- it does not update the volume info in ZINTERNALRESOURCES.ZFILESYSTEMVOLUME. ZINTERNALRESOURCES.ZFILESYSTEMBOOKMARK points to the now updated bookmark, which appears to be correct, but if the volume changed, the volume info in the ZFILESYSTEMVOLUME table pointed at by ZINTERNALRESOURCES.ZFILESYSTEMVOLUME will be incorrect.

Should the script also add a new volume (if necessary) to ZFILESYSTEMVOLUME and update the pointer in ZINTERNALRESOURCES? Nothing appears to be broken but it does leave an inconsistency in the database.

The current implementation uses CFURLCreateByResolvingBookmarkData which fails if the target file isn't present. This means Photos bookmarks cannot be migrated to a different path (unless copies of the target photos were present in both the old location and the new location). If the bookmark resolution is replaced with mac_alias calls, the URL could be extracted even if the target isn't present and then changed, according to some mapping, to the new location.

Would still need a way to map old location to new location.

The following python code shows how to extract the bookmark URL.

"""Extract file path from a CFURL bookmark without calling Objective C"""
import os

from mac_alias import Bookmark, kBookmarkPath


def get_bookmark_path(bookmark_data: bytes) -> str:
    """Get the path from a CFURL file bookmark
    This works without calling CFURLCreateByResolvingBookmarkData
    which fails if the target file does not exist
    """
    try:
        bookmark = Bookmark.from_bytes(bookmark_data)
    except Exception as e:
        raise ValueError(f"Invalid bookmark: {e}")
    path_components = bookmark.get(kBookmarkPath, None)
    if not path_components:
        return None
    return "/" + os.path.join(*path_components)


if __name__ == "__main__":
    import sys

    bookmark_file = sys.argv[1]
    with open(bookmark_file, "rb") as f:
        bookmark_data = f.read()
    bookmark_path = get_bookmark_path(bookmark_data)
    print(f"{bookmark_path=}")