How can I skip deleting folders except a specified folder for a web deploy (msdeploy) sync?

Question

Suppose I have a destination folder structure that looks like this:

D:\DEPLOY\DEST
│   0.txt
│
├───a
│       a.txt
│
└───b
    ├───b1
    │   │   b1.txt
    │   │
    │   ├───b1a
    │   │       b1a.txt
    │   │
    │   └───b1b
    │           b1b.txt
    │
    └───b2
            b2.txt

I also have a source folder structure that looks like this:

D:\DEPLOY\SOURCE
└───b
    └───b1
        └───b1a
                b1a-new.txt

I would like to synchronize the source to the destination, but only below the \b\\b1\b1a path. To do that, when running MSDeploy, I add a skip rule matching all dirPaths not containing this path:

msdeploy -verb:sync 
         -source:contentPath=D:\deploy\source
         -dest:contentPath=D:\deploy\dest
         -skip:skipAction=delete,objectName=dirPath,absolutePath='(?!\\b\\b1\\b1a)'
         -whatif

resulting in:

Info: Deleting file (D:\deploy\dest\0.txt).
Info: Deleting file (D:\deploy\dest\b\b1\b1.txt).
Info: Adding file (D:\deploy\dest\b\b1\b1a\b1a-new.txt).
Info: Deleting file (D:\deploy\dest\b\b1\b1a\b1a.txt).
Total changes: 4 (1 added, 3 deleted, 0 updated, 0 parameters changed, 0 bytes copied)

To my surprise, this does more than expected. MSDeploy also deletes the files 0.txt and b1.txt, which are under a dirPath that I expect to be skipped based on the regex. I tried various permutations of the absolutePath regex, but to no avail.

What should I be doing instead? Or is this beyond the possibilities of msdeploy?

Note: this example is simplified. In reality my source is package, not a contentPath. That is why the obvious answer of syncing at the b\b1\b1a-level would not apply.

Answer 1

You've specified that you don't want it to delete directories outside that folder, but your skip rule says nothing about files. Just remove ,objectName=dirPath from your skip directive and it will skip deletes on any provider.

As an aside, skip rules are actually quite nuanced in their behavior. I have a blog post that digs into it which might help: Demystifying MSDeploy skip rules