Skip to main content

Extend NuGet Server to store packages on Azure Blob Storage

Continuing the last post about Azure Web Apps and Data Disk size limit let's assume that you want to host inside a Web App a NuGet Server. The server would require more storage than you have available on the current tier that you use and upgrading the tier would be too expensive.

The good part with NuGet is that we are talking about an open-source project that can be modified and extended depending on our needs and requirements. The current NuGet implementation allows us to store packages on disk or to fetch them from external data sources as long as they are available over HTTP. Basically, they are allowing us to have a remote repository 

An interesting idea would be to extend NuGet to allow us to store package content inside Azure Blob Storage and not on the disk. This would involve the capability to fetch the payload of packages from Blob storage directly, without having to store them on a local disk.
Taking into account the current implementation and how NuGet libraries are structured internally, I think that it can be achieved easily with a minimal effort. After a short review (15 minutes) of NuGet libraries, I identified a few interfaces and classes that are relevant to do such a thing. 

The most important classes/interfaces that we need to be aware of are:
  1. IServerPackageRepository: Provides access to the file system, in this case, we need to rewrite it to support Blob storage
  2. IPackageService & PackageService: Package download capabilities 
  3. IPackage: Defines a package with all the supported functionality
Beside this, you might be interested to take a look on:
1. Core interfaces used to download and access package payload
  • IPackageDownloader
  • IPackageContentReader
  • IAsyncPackageContentReader
2. Core implementation to read and extract packages
  • PackageReaderBase
  • PackageFolderReader
  • PackageExtractor
3. Mechanisms used to access package content
  • NuGet.Protocol.LocalRepository
  • NuGet.Protocol.RemoteRepositories
  • NuGet.Protocol.PackagesFolder
  • NuGet.Protocol.HttpSource
4. Core factory to create and register specific repository providers
  • FactoryExtensionsV3
Once we implemented the NuGet extension for Azure Storage, we would need to rebind the NuGet 'kernel' to use our own implementations of Package Repository and custom Package implementation. 

The idea is not new, there were already other people that tried it, but because of lack of time they were not able to finish it. If you want to get some inspiration or to give a hand, please visit the following GitHub repository - Even if it was not updated in the last few years, it is still a good starting point. 


Popular posts from this blog

ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded

Today blog post will be started with the following error when running DB tests on the CI machine:
threw exception: System.InvalidOperationException: The Entity Framework provider type 'System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer' registered in the application config file for the ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application. See for more information. at System.Data.Entity.Infrastructure.DependencyResolution.ProviderServicesFactory.GetInstance(String providerTypeName, String providerInvariantName) This error happened only on the Continuous Integration machine. On the devs machines, everything has fine. The classic problem – on my machine it’s working. The CI has the following configuration:

TeamCity.NET 4.51EF 6.0.2VS2013
It seems that there …

Entity Framework (EF) TransactionScope vs Database.BeginTransaction

In today blog post we will talk a little about a new feature that is available on EF6+ related to Transactions.
Until now, when we had to use transaction we used ‘TransactionScope’. It works great and I would say that is something that is now in our blood.
using (var scope = new TransactionScope(TransactionScopeOption.Required)) { using (SqlConnection conn = new SqlConnection("...")) { conn.Open(); SqlCommand sqlCommand = new SqlCommand(); sqlCommand.Connection = conn; sqlCommand.CommandText = ... sqlCommand.ExecuteNonQuery(); ... } scope.Complete(); } Starting with EF6.0 we have a new way to work with transactions. The new approach is based on Database.BeginTransaction(), Database.Rollback(), Database.Commit(). Yes, no more TransactionScope.
In the followi…

GET call of REST API that contains '/'-slash character in the value of a parameter

Let’s assume that we have the following scenario: I have a public HTTP endpoint and I need to post some content using GET command. One of the parameters contains special characters like “\” and “/”. If the endpoint is an ApiController than you may have problems if you encode the parameter using the http encoder.
using (var httpClient = new HttpClient()) { httpClient.BaseAddress = baseUrl; Task<HttpResponseMessage> response = httpClient.GetAsync(string.Format("api/foo/{0}", "qwert/qwerqwer"))); response.Wait(); response.Result.EnsureSuccessStatusCode(); } One possible solution would be to encode the query parameter using UrlTokenEncode method of HttpServerUtility class and GetBytes method ofUTF8. In this way you would get the array of bytes of the parameter and encode them as a url token.
The following code show to you how you could write the encode and decode methods.