I am using Visual Studio Online - Package Manager Preview, along with the new build system. The package manager preview adds a number of build steps, including a "NuGet Publisher" step, which should push packages to the private feed hosted by Visual Studio Online.
Now the documentation is a little out of step here. As is the documentation on auth and personal access tokens. There are some indications that you shouldn't need auth between VSO and the Package Manager as long as you have permissions set up (the build service account has permissions to the service endpoint and to the package manager extension). The actual build step asks you to select from your list of Service Endpoints, so that is what I have attempted.
When I place no credentials on the Service Endpoint, I get the error:
Server Key must be set, set the password on the generic service
When I attempt to place the API key against the Service Endpoint it seems to be discarded on save... and the error changes to:
2015-11-18T08:35:24.5678951Z Invoking nuget with push C:\a\1\s\EventViewer\bin\Release\Project.Name.1.1.12.0.nupkg -s https://example.pkgs.visualstudio.com/DefaultCollection/_packaging/example/nuget/v3/index.json usfusmx4ez6mlfqwpp2abzc7e37denfcp7bxsep2hqij3tp4qwvq on C:\a\1\s\EventViewer\bin\Release\Project.Name.1.1.12.0.nupkg
2015-11-18T08:35:24.5688946Z C:\LR\MMS\Services\Mms\TaskAgentProvisioner\Tools\agents\default\agent\worker\tools\NuGet.exe push C:\a\1\s\EventViewer\bin\Release\Project.Name.1.1.12.0.nupkg -s https://example.pkgs.visualstudio.com/DefaultCollection/_packaging/Example/nuget/v3/index.json usfusmx4ez6mlfqwpp2abzc7e37denfcp7bxsep2hqij3tp4qwvq
2015-11-18T08:35:25.3467312Z Please provide credentials for: https://example.pkgs.visualstudio.com/DefaultCollection/_packaging/Example/nuget/v3/index.json
2015-11-18T08:35:25.3667189Z ##[error]Object reference not set to an instance of an object.
2015-11-18T08:35:25.3677179Z UserName: Password:
2015-11-18T08:35:25.4647059Z ##[error]Unexpected exit code 1 returned from tool NuGet.exe
I have also attempted to use a personal access token to no avail.
How do I get the publish step working?
The in-box NuGet Publish task has two options: "external" feeds and "internal" feeds. External feeds are intended for 3rd party services like NuGet.org, Artifactory, and expect a service connection with an API key.
Internal feeds are those hosted by Team Services. Instead of a service connection, you add the URL of the feed's NuGet endpoint. The build system relies on the Project Collection Build Service (for collection-scoped build definitions) or Project Build Service (for "this project"-scoped build defs) being a Reader or Contributor to the feed. Docs for all that are available here.
UPDATE: It is all fixed now so you can use the standard packaging steps in vNext and they work like a charm.
For the time being, I am substituting the NuGet Publisher step with a PowerShell build step.
This slots into the build after the "NuGet Packager" step and allows me to specify all of the credentials by setting up a package source before pusing the package.
I landed here because I'm researching/configuring an internal deploy -- where I'm running my own NuGet Server (nuget.server, as opposed to visual studio online). The error was the same (or has similar text):
My solution, it turned out, was that the URL wasn't right. The correct version is:
http://server-name/NuGet/api/v2/package
For completeness, I had:
http://server-name/NuGet/
which was wrong.