Renaming a package ID is a potentially destructive action and one we don’t recommend doing. Why? Well if any other packages depend on your package, you’ve effectively broken them if you change your package ID.

For example, today I wanted to rename a poorly named package, MicrosoftWebMvc, to Mvc2Futures. What I ended up doing is recreating the same package with the new ID and uploading it. That way existing packages that depend on MicrosoftWebMvc aren’t broken.

But now, I have two packages that have the same functionality, but different IDs. Wouldn’t it be nice to eventually remove the old one? I guess I could if I knew that no other package had a dependency on it.

This is where the benefit of having an OData service over the packages in the gallery comes in quite useful. It allows us to construct ad-hoc queries we hadn’t accounted for in our API via an URL. Here’s the URL that shows me a list of all packages that depend on MicrosoftWebMvc.

http://packages.nuget.org/v1/FeedService.svc/Packages?$filter=substringof(‘MicrosoftWebMvc’,%20Dependencies)%20eq%20true&$select=Id,Dependencies

Notice that we’re searching the Dependencies node for the substring “MicrosoftWebMvc” anywhere in it. If my package ID was “web”, this would not be a good query to run, so you might need to tweak it for your use case.

Also, this query only detects direct dependencies. It doesn’t detect transitive dependencies. However, in this case, that’s good enough for my needs.

With this list in hand, I can now approach the MvcContrib folks (who are the only ones that depend on it), and suggest they update their existing packages in place to point to the one with the new ID.

If they do this, am I safe to delete MicrosoftWebMvc?

Not necessarily.

I really need to think twice before I remove the MicrosoftWebMvcpackage because it’s already been downloaded 939 times. For those users who’ve installed it into their applications, they’ll never get updates for that package.

In this particular case, this is not a problem because we never plan to update the Mvc2Futures package. But for a package that’s more widely used and frequently updated, this would be a bigger concern.

In the meanwhile, what I will do is update MicrosoftWebMvc to be an empty package that depends on the correct package. That’s probably a good plan while I wait for packages that depend on it to update.