Unable to push nuGet packages to GitLab with dotnet CLI due to Unauthorized error

GitLab now supports nuget public and private feed repository.I've got a public project (e.g: https://gitlab.com/sunnyatticsoftware/sasw-test-support)I create an access token for my user with api and write_repository (e.g: AAABBBCCCDDD)

I create a group variable in my CI/CD: SASW_API_ACCESS_TOKEN: AAABBBCCCDDD. All normal.

Then I create the multi stage CI/CD script to build, pack and publish.When attempting to publish the nuGet package with the following:dotnet nuget push **/*.nupkg --source https://gitlab.com/api/v4/projects/17141695/packages/nuget/index.json --api-key AAABBBCCCDDD --skip-duplicate

I get the error:

info : Pushing Sasw.TestSupport.2.0.2.nupkg to 'https://gitlab.com/api/v4/projects/17141695/packages/nuget'...info :   PUT https://gitlab.com/api/v4/projects/17141695/packages/nuget/info :   Unauthorized https://gitlab.com/api/v4/projects/17141695/packages/nuget/ 397mserror: Response status code does not indicate success: 401 (Unauthorized).ERROR: Job failed: exit code 1

The documentation doesn't mention anything special, but I notice that when using the (legacy?) nuget CLI it passes a username. Dotnet CLI, however, doesn't support username, just API KEY.

Any idea why this is not working?

This is my CI/CD script:

variables:  GITLAB_RUNNER_DOTNET_CORE: mcr.microsoft.com/dotnet/core/sdk:3.1  NUGET_REPOSITORY: https://gitlab.com/api/v4/projects/${CI_PROJECT_ID}/packages/nuget/index.json  NUGET_API_KEY: $SASW_API_ACCESS_TOKEN  NUGET_FOLDER_NAME: nupkgs  NUGET_VERSION_SUFFIX: $SASW_PRERELEASE_SUFFIXstages:  - build  - pack  - release#Docker imageimage: $GITLAB_RUNNER_DOTNET_CORE#Jobsci:  stage: build  script:    - dotnet restore --no-cache --force    - dotnet build --configuration Release --no-restore    #- dotnet vstest test/*UnitTests/bin/Release/**/*UnitTests.dll    #- dotnet vstest test/*IntegrationTests/bin/Release/**/*IntegrationTests.dllpack-prerelease:  stage: pack  script:    - dotnet pack *.sln --configuration Release --output $NUGET_FOLDER_NAME --version-suffix $NUGET_VERSION_SUFFIX --include-symbols -p:SymbolPackageFormat=snupkg  artifacts:    paths:    - $NUGET_FOLDER_NAME    expire_in: 1 week  except:    - masterpack-release:  stage: pack  script:    - dotnet pack *.sln --configuration Release --output $NUGET_FOLDER_NAME  artifacts:    paths:    - $NUGET_FOLDER_NAME    expire_in: 1 week  only:    - masterpublish-nuget:  stage: release  script:    - dotnet nuget push **/*.nupkg --source $NUGET_REPOSITORY --api-key $NUGET_API_KEY --skip-duplicate

PS: The project is public, so in case it's needed have a look at: https://gitlab.com/sunnyatticsoftware/sasw-test-support/-/jobs/451080235

UPDATE 1: Further verbosity from my local linux console

$ dotnet nuget -v Debug push **/*.nupkg --source https://gitlab.com/api/v4/projects/17141695/packages/nuget/index.json --api-key cBwt5_hidden_ --skip-duplicatetrace: NuGet Command Line Version: 5.4.0.2info : Pushing Sasw.TestSupport.2.0.2.nupkg to 'https://gitlab.com/api/v4/projects/17141695/packages/nuget'...info :   PUT https://gitlab.com/api/v4/projects/17141695/packages/nuget/info :   Unauthorized https://gitlab.com/api/v4/projects/17141695/packages/nuget/ 1159mserror: Response status code does not indicate success: 401 (Unauthorized).trace: System.AggregateException: One or more errors occurred. (Response status code does not indicate success: 401 (Unauthorized).)trace:  ---> System.Net.Http.HttpRequestException: Response status code does not indicate success: 401 (Unauthorized).trace:    at System.Net.Http.HttpResponseMessage.EnsureSuccessStatusCode()trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.EnsureSuccessStatusCode(HttpResponseMessage response, Nullable`1 codeNotToThrow, ILogger logger)trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.<>c__DisplayClass23_0.<PushPackageToServer>b__0(HttpResponseMessage response)trace:    at NuGet.Protocol.HttpSource.ProcessResponseAsync[T](HttpSourceRequest request, Func`2 processAsync, SourceCacheContext cacheContext, ILogger log, CancellationToken token)trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.PushPackageToServer(String source, String apiKey, String pathToPackage, Int64 packageSize, Boolean noServiceEndpoint, Boolean skipDuplicate, TimeSpan requestTimeout, ILogger logger, CancellationToken token)trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.PushPackageCore(String source, String apiKey, String packageToPush, Boolean noServiceEndpoint, Boolean skipDuplicate, TimeSpan requestTimeout, ILogger log, CancellationToken token)trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.PushPackage(String packagePath, String source, String apiKey, Boolean noServiceEndpoint, Boolean skipDuplicate, TimeSpan requestTimeout, ILogger log, CancellationToken token, Boolean isSnupkgPush)trace:    at NuGet.Protocol.Core.Types.PackageUpdateResource.Push(String packagePath, String symbolSource, Int32 timeoutInSecond, Boolean disableBuffering, Func`2 getApiKey, Func`2 getSymbolApiKey, Boolean noServiceEndpoint, Boolean skipDuplicate, SymbolPackageUpdateResourceV3 symbolPackageUpdateResource, ILogger log)trace:    at NuGet.Commands.PushRunner.Run(ISettings settings, IPackageSourceProvider sourceProvider, String packagePath, String source, String apiKey, String symbolSource, String symbolApiKey, Int32 timeoutSeconds, Boolean disableBuffering, Boolean noSymbols, Boolean noServiceEndpoint, Boolean skipDuplicate, ILogger logger)trace:    at NuGet.CommandLine.XPlat.PushCommand.<>c__DisplayClass0_1.<<Register>b__1>d.MoveNext()trace:    --- End of inner exception stack trace ---trace:    at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)trace:    at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)trace:    at System.Threading.Tasks.Task`1.get_Result()trace:    at Microsoft.Extensions.CommandLineUtils.CommandLineApplication.<>c__DisplayClass56_0.<OnExecute>b__0()trace:    at Microsoft.Extensions.CommandLineUtils.CommandLineApplication.Execute(String[] args)trace:    at NuGet.CommandLine.XPlat.Program.MainInternal(String[] args, CommandOutputLogger log)

UPDATE 2: Alexey's answer is the proper one and up to date as per April 2021. GitLab has improved Nuget support in the last year and now it's possible to easily push packages to the repo package registry and have readacces on Nuget feed at project level or group level using deploy tokens.