readme.md

Extensions

Dev Home is an app extension host which uses out-of-process COM to talk to external COM Server processes that declare themselves to be extensions of Dev Home.

Dev Home currently supports extending two interfaces through the Extension SDK. In addition, extensions can provide widgets to Dev Home using Widget providers.

Extension basics

Each extension lives as a separate, packaged Windows application and manages its own lifecycle. The extension applications declare themselves to be extensions of Dev Home through the manifest file.

An extension can provide functionality for one or more extensibility points. Currently, Dev Home supports two extensibility points:

• Developer IDs: Allow developers to sign in and out of a service by implementing the IDeveloperIdProvider interface.
• Repositories: Allow developers to get available repositories associated with their Developer IDs or parse repositories from URLs and clone them by implementing the IRepositoryProvider interface.

Read more about Provider interfaces below. Each extension also must have a class that implements IExtension. DevHome needs to create an instance of this class. The GUID of this class must be reflected in the manifest. See Sample Extension

Extension manifest

The package.appxmanifest file must define a COM Server (which includes the class ID of the Extension class) and AppExtension properties declaring extension information.

<Extensions>
  ...
  <com:Extension Category="windows.comServer">
    <com:ComServer>
      <com:ExeServer Executable="ExtensionName.exe" Arguments="-RegisterProcessAsComServer" DisplayName="Sample Extension">
        <com:Class Id="<Extension Class GUID>" DisplayName="Sample Extension" />
      </com:ExeServer>
    </com:ComServer>
  </com:Extension>

  <uap3:AppExtension Name="com.microsoft.devhome"
                     Id="YourApplicationUniqueId"
                     PublicFolder="Public"
                     DisplayName="Sample Extension"
                     Description="This is a sample description.">
    <uap3:Properties>
      <DevHomeProvider>
        <Activation>
          <CreateInstance ClassId="<Extension Class GUID>" />
        </Activation>
        <SupportedInterfaces>
          <DeveloperId />
          <Repository />
        </SupportedInterfaces>
      </DevHomeProvider>
    </uap3:Properties>
  </uap3:AppExtension>
</Extensions>

Provider Interfaces

IDeveloperIdProvider

Developer ID-related scenarios can be extended by:

• Implementing IDeveloperIdProviderInterface
• In the manifest, declaring IDeveloperId as one of the supported interfaces

public interface IDeveloperIdProvider : global::System.IDisposable
{
  string GetName();
  global::System.Collections.Generic.IEnumerable<IDeveloperId> GetLoggedInDeveloperIds();
  global::Windows.Foundation.IAsyncOperation<IDeveloperId> LoginNewDeveloperIdAsync();
  void LogoutDeveloperId(IDeveloperId developerId);
  IExtensionAdaptiveCardSession GetLoginAdaptiveCardSession();
  event global::System.EventHandler<IDeveloperId> LoggedIn;
  event global::System.EventHandler<IDeveloperId> LoggedOut;
  event global::System.EventHandler<IDeveloperId> Updated;
}

public interface IDeveloperId
{
  string LoginId();
  string Url();
}

IRepositoryProvider

Repository-related scenarios can be extended by:

• Implementing the IRepositoryProvider interface
• In the manifest, declaring IRepository as one of the supported interfaces

public interface IRepositoryProvider : global::System.IDisposable
{
  global::Windows.Foundation.IAsyncOperation<global::System.Collections.Generic.IEnumerable<IRepository>> GetRepositoriesAsync(IDeveloperId developerId);
  
  global::Windows.Foundation.IAsyncOperation<IRepository> ParseRepositoryFromUrlAsync(global::System.Uri uri);
  
  string DisplayName { get; }
}

public interface IRepository
{
  [global::Windows.Foundation.Metadata.Overload(@"CloneRepositoryAsync")]
  global::Windows.Foundation.IAsyncAction CloneRepositoryAsync(string cloneDestination, IDeveloperId developerId);

  [global::Windows.Foundation.Metadata.Overload(@"CloneRepositoryAsync2")]
  global::Windows.Foundation.IAsyncAction CloneRepositoryAsync(string cloneDestination);
  
  string DisplayName { get; }
  
  bool IsPrivate { get; }
  
  global::System.DateTimeOffset LastUpdated { get; }
  
  string OwningAccountName { get; }
}

Sequence diagram

Runtime logic

At startup, Dev Home iterates through the app catalog looking for any extensions and adds them to a dictionary.

private readonly IDictionary<string, IReadOnlyList<AppExtension>> _extensions = new Dictionary<string, IReadOnlyList<AppExtension>>();

Any internal tools can retrieve a read-only list of extensions for a given extension point as follows:

var extensionService = App.GetService<IExtensionService>();
var extensions = extensionService.GetExtensions("widget");