2 files changed, 48 insertions, 0 deletions

diff --git a/src/api/wix/WixToolset.Extensibility/Data/IExtensionCacheLocation.cs b/src/api/wix/WixToolset.Extensibility/Data/IExtensionCacheLocation.cs
new file mode 100644
index 00000000..53158875
--- /dev/null
+++ b/src/api/wix/WixToolset.Extensibility/Data/IExtensionCacheLocation.cs
@@ -0,0 +1,41 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixToolset.Extensibility.Data
+{
+    /// <summary>
+    /// Extension cache location scope.
+    /// </summary>
+    public enum ExtensionCacheLocationScope
+    {
+        /// <summary>
+        /// Project extension cache location.
+        /// </summary>
+        Project,
+
+        /// <summary>
+        /// User extension cache location.
+        /// </summary>
+        User,
+
+        /// <summary>
+        /// Machine extension cache location.
+        /// </summary>
+        Machine,
+    }
+
+    /// <summary>
+    /// Location where extensions may be cached.
+    /// </summary>
+    public interface IExtensionCacheLocation
+    {
+        /// <summary>
+        /// Path for  the extension cache location.
+        /// </summary>
+        string Path { get; }
+
+        /// <summary>
+        /// Scope for the extension cache location.
+        /// </summary>
+        ExtensionCacheLocationScope Scope { get; }
+    }
+}
diff --git a/src/api/wix/WixToolset.Extensibility/Services/IExtensionManager.cs b/src/api/wix/WixToolset.Extensibility/Services/IExtensionManager.cs
index 8e49c38d..fe939a59 100644
--- a/src/api/wix/WixToolset.Extensibility/Services/IExtensionManager.cs
+++ b/src/api/wix/WixToolset.Extensibility/Services/IExtensionManager.cs
@@ -4,6 +4,7 @@ namespace WixToolset.Extensibility.Services
 {
     using System.Collections.Generic;
     using System.Reflection;
+    using WixToolset.Extensibility.Data;
 
     /// <summary>
     /// Loads extensions and uses the extensions' factories to provide services.
@@ -33,6 +34,12 @@ namespace WixToolset.Extensibility.Services
         void Load(string extensionReference);
 
         /// <summary>
+        /// Gets extensions cache locations.
+        /// </summary>
+        /// <returns>List of cache locations where extensions may be found.</returns>
+        IReadOnlyCollection<IExtensionCacheLocation> GetCacheLocations();
+
+        /// <summary>
         /// Gets extensions of specified type from factories loaded into the extension manager.
         /// </summary>
         /// <typeparam name="T">Type of extension to get.</typeparam>