Flag to skip missing symlinks

[cadorn]

If I have a symlink that points to a path that does not exist it will currently throw.

I need a flag to ignore these errors and have the hashing continue.

In this case, skip trying to hash the targeted content of the symlink and just hash the name of the symlink as well as the target path. This will then generate a new hash whenever the symlink is renamed or pointed to a different path.

[marc136]

I know that this is an old issue @cadorn, but can you give me an example of the error that you received?
On my system I only saw ENOENT when trying to hash a symbolic link where the target was not existing.
You can see my take in 59853ae it in the fix_#41 branch.
Edit: I added the general approach to another branch

[marc136]

I realized that I misunderstood the requirements. I am working on a more general solution

[marc136]

I added a solution that not only adds this behavior, but also allows general settings for soft links, like always also hashing the target path or to skip them completely.
https://github.com/marc136/node-folder-hash/blob/main/test/symbolic-links.js
Edit: changed link

[cadorn]

Very nice!

IIRC there was another issue that caused us to have to swap out this lib. I'll see what it was so you can harden it even more.

[marc136]

Thanks, that sounds great.
Do you also recall why you had symlinks that could not be accessed? Was it a permission issue or actually forgotten links?

[cadorn]

Do you also recall why you had symlinks that could not be accessed? Was it a permission issue or actually forgotten links?

We have cases where we have relative symlinks that do not resolve until they are copied to a new location. But we need to hash them before copying. So for a symlink with value ./foo we need the hash('./foo') to detect if the symlink has changed.

[marc136]

Ok, thank you.

[cadorn]

Just to follow up on the symlink issue which I presume is fixed now. Will try soon.

This is the patch we are currently running on top of https://github.com/marc136/node-folder-hash/blob/02398bb0712b301df10e65054b6c83a61ea635f8/index.js

[cadorn]

The new symbolicLinks.hashTargetPath option is documented as: Set to true to add the resolved link target to the hash (uses fs.readlink)

The word resolved is throwing me off. It implies that the link target is run through realpath which does not seem to be the case in the code.

Should it not be something like?: Set to true to add the link target to the hash (uses fs.readlink)

[cadorn]

Also, the follow property values seem a bit overloaded.
Maybe:

{
    "include": true,   // true, false
    "follow": true    // true, false
}