Host Model

HostModel is a library used by the SDK to perform certain transformations on host executables. The main services implemented in HostModel are:

• AppHost rewriter: Embeds the App Name into the AppHost executable. On Windows, also copies resources from App.dll to the AppHost.

• ComHost rewriter: Creates a ComHost with an embedded CLSIDMap file to map CLSIDs to .NET Classes.

• Single-file bundler: Embeds an application and its dependencies into the AppHost, to publish a single executable, as described here.

The HostModel library is in the Runtime repo because:

• The implementations of the host and HostModel are closely related, which facilitates easy development, update, and testing.
• Separating the HostModel implementation from SDK repo repo aligns with code ownership, and facilitates maintenance.

The build targets/tasks that use the HostModel library are in the SDK repo because:

• This facilitates the MSBuild tasks to be multi-targeted.
• It helps generate localized error messages, since SDK repo has the localization infrastructure.