After creating a connector maven central and running the indexing scheduled tasks, many Maven packages do not list the main jar file in the list of files that are included with the package.

It appears that this is maybe happening if the pom file does not explicitly have a packaging element with a value of "jar".

An example is shown in the image below, but this behaviour is seen with many packages.

The main jar file kotlin-stdlib-2.3.20.jar is not listed.

If you request this file directly it will be downloaded and then appear in the list of files.

This means that if you attempt to promote a package from a feed with an external connector to a curated feed without directly requesting the jar file first, the jar will not be promoted and the package will not work from the curated feed.

Is the behaviour that we are seeing intended or do we have something configured incorrectly?

I'm afraid this behavior is expected because kotlin-stdlib-2.3.20.jar is not in the downloaded index file. There's is no file-listing API, which means there's no way to know what should be there otherwise.

The Maven client downloads "blindly downloads" some files, and "silently accepts" a 404 for other files. When it's downloaded (cached), then ProGet knows about it. So, you really need to download the artifacts first if you want to make a curated feed I'm afraid.

-- Dean