Fetch should report progress through callbacks.

LibGit2Sharp.Tests/RemoteFixture.cs

@@ -103,7 +103,7 @@ public void CanFetchIntoAnEmptyRepository(string url)
                 }
 
                 // Perform the actual fetch
-                remote.Fetch(new FetchProgress(), onUpdateTips: expectedFetchState.RemoteUpdateTipsHandler);
+                remote.Fetch(onUpdateTips: expectedFetchState.RemoteUpdateTipsHandler);
 
                 // Verify the expected
                 expectedFetchState.CheckUpdatedReferences(repo);
@@ -141,7 +141,7 @@ public void CanFetchAllTagsIntoAnEmptyRepository(string url)
                 }
 
                 // Perform the actual fetch
-                remote.Fetch(new FetchProgress(), TagFetchMode.All, onUpdateTips: expectedFetchState.RemoteUpdateTipsHandler);
+                remote.Fetch(TagFetchMode.All, onUpdateTips: expectedFetchState.RemoteUpdateTipsHandler);
 
                 // Verify the expected
                 expectedFetchState.CheckUpdatedReferences(repo);

LibGit2Sharp/Core/GitTransferProgress.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace LibGit2Sharp.Core
+{
+    /// <summary>
+    ///   Managed structure corresponding to git_transfer_progress native structure.
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct GitTransferProgress
+    {
+        public uint total_objects;
+        public uint indexed_objects;
+        public uint received_objects;
+        public UIntPtr received_bytes;
+    }
+}

LibGit2Sharp/Core/NativeMethods.cs

@@ -784,7 +784,7 @@ internal static extern int git_tag_delete(
         [DllImport(libgit2)]
         internal static extern void git_threads_shutdown();
 
-        internal delegate void git_transfer_progress_callback(IntPtr stats, IntPtr payload);
+        internal delegate void git_transfer_progress_callback(ref GitTransferProgress stats, IntPtr payload);
 
         [DllImport(libgit2)]
         internal static extern int git_tree_create_fromindex(out GitOid treeOid, IndexSafeHandle index);

LibGit2Sharp/Core/Proxy.cs

@@ -6,6 +6,7 @@
 using System.Runtime.InteropServices;
 using System.Threading;
 using LibGit2Sharp.Core.Handles;
+using LibGit2Sharp.Handlers;
 
 // ReSharper disable InconsistentNaming
 namespace LibGit2Sharp.Core
@@ -1046,12 +1047,13 @@ public static void git_remote_disconnect(RemoteSafeHandle remote)
             }
         }
 
-        // TODO: callback & payload
-        public static void git_remote_download(RemoteSafeHandle remote, ref long bytes, ref GitIndexerStats indexerStats)
+        public static void git_remote_download(RemoteSafeHandle remote, TransferProgressHandler onTransferProgress)
         {
             using (ThreadAffinity())
             {
-                int res = NativeMethods.git_remote_download(remote, null, IntPtr.Zero);
+                NativeMethods.git_transfer_progress_callback cb = TransferCallbacks.GenerateCallback(onTransferProgress);
+
+                int res = NativeMethods.git_remote_download(remote, cb, IntPtr.Zero);
                 Ensure.Success(res);
             }
         }

LibGit2Sharp/Handlers.cs

@@ -1,12 +1,19 @@
 using System;
+using LibGit2Sharp.Core;
 
 namespace LibGit2Sharp.Handlers
 {
     /// <summary>
-    ///   Delegate definition to handle Progress callback.
+    ///   Delegate definition to handle Progress callback. 
+    ///   Returns the text as reported by the server. The text
+    ///   in the serverProgressOutput parameter is not delivered
+    ///   in any particular units (i.e. not necessarily delivered
+    ///   as whole lines) and is likely to be chunked as partial lines.
     /// </summary>
-    /// <param name="message">Progress message.</param>
-    public delegate void ProgressHandler(string message);
+    /// <param name="serverProgressOutput">text reported by the server. 
+    ///   Text can be chunked at arbitrary increments (i.e. can be composed
+    ///   of a partial line of text).</param>
+    public delegate void ProgressHandler(string serverProgressOutput);
 
     /// <summary>
     ///   Delegate definition to handle UpdateTips callback.
@@ -23,4 +30,10 @@ namespace LibGit2Sharp.Handlers
     /// <param name="RemoteCompletionType"></param>
     /// <returns></returns>
     public delegate int CompletionHandler(RemoteCompletionType RemoteCompletionType);
+
+    /// <summary>
+    ///   Delegate definition for transfer progress callback.
+    /// </summary>
+    /// <param name="progress">The <see cref = "TransferProgress" /> object containing progress information.</param>
+    public delegate void TransferProgressHandler(TransferProgress progress);
 }

LibGit2Sharp/LibGit2Sharp.csproj

@@ -70,6 +70,7 @@
     <Compile Include="ContentChanges.cs" />
     <Compile Include="Core\GitCheckoutOpts.cs" />
     <Compile Include="Core\GitConfigEntry.cs" />
+    <Compile Include="Core\GitTransferProgress.cs" />
     <Compile Include="Core\Proxy.cs" />
     <Compile Include="Handlers.cs" />
     <Compile Include="ReferenceCollectionExtensions.cs" />
@@ -79,7 +80,6 @@
     <Compile Include="RemoteCompletionType.cs" />
     <Compile Include="TagCollectionExtensions.cs" />
     <Compile Include="Core\Compat\Environment.cs" />
-    <Compile Include="FetchProgress.cs" />
     <Compile Include="Core\FilePath.cs" />
     <Compile Include="Core\FilePathExtensions.cs" />
     <Compile Include="Core\FilePathMarshaler.cs" />
@@ -121,6 +121,8 @@
     <Compile Include="Note.cs" />
     <Compile Include="RepositoryNotFoundException.cs" />
     <Compile Include="TagFetchMode.cs" />
+    <Compile Include="TransferCallbacks.cs" />
+    <Compile Include="TransferProgress.cs" />
     <Compile Include="TreeChanges.cs" />
     <Compile Include="TreeEntryChanges.cs" />
     <Compile Include="LibGit2SharpException.cs" />

LibGit2Sharp/Remote.cs

@@ -51,20 +51,19 @@ internal static Remote BuildFromPtr(RemoteSafeHandle handle, Repository repo)
         /// <summary>
         ///   Fetch from the <see cref = "Remote" />.
         /// </summary>
-        /// <param name="progress">The <see cref = "FetchProgress" /> datastructure where the progress of the fetch is reported.</param>
         /// <param name="tagFetchMode">Optional parameter indicating what tags to download.</param>
         /// <param name="onProgress">Progress callback. Corresponds to libgit2 progress callback.</param>
         /// <param name="onCompletion">Completion callback. Corresponds to libgit2 completion callback.</param>
         /// <param name="onUpdateTips">UpdateTips callback. Corresponds to libgit2 update_tips callback.</param>
-        public virtual void Fetch(FetchProgress progress = null,
+        /// <param name="onTransferProgress">Callback method that transfer progress will be reported through.
+        ///   Reports the client's state regarding the received and processed (bytes, objects) from the server.</param>
+        public virtual void Fetch(
             TagFetchMode tagFetchMode = TagFetchMode.Auto,
             ProgressHandler onProgress = null,
             CompletionHandler onCompletion = null,
-            UpdateTipsHandler onUpdateTips = null)
+            UpdateTipsHandler onUpdateTips = null,
+            TransferProgressHandler onTransferProgress = null)
         {
-            progress = progress ?? new FetchProgress();
-            progress.Reset();
-
             using (RemoteSafeHandle remoteHandle = Proxy.git_remote_load(repository.Handle, this.Name, true))
             {
                 var callbacks = new RemoteCallbacks(onProgress, onCompletion, onUpdateTips);
@@ -85,8 +84,7 @@ public virtual void Fetch(FetchProgress progress = null,
                 try
                 {
                     Proxy.git_remote_connect(remoteHandle, GitDirection.Fetch);
-
-                    Proxy.git_remote_download(remoteHandle, ref progress.bytes, ref progress.IndexerStats.gitIndexerStats);
+                    Proxy.git_remote_download(remoteHandle, onTransferProgress);
                 }
                 finally
                 {

LibGit2Sharp/RepositoryExtensions.cs

@@ -151,22 +151,24 @@ public static Commit Commit(this IRepository repository, string message, Signatu
         /// </summary>
         /// <param name="repository">The <see cref = "Repository" /> being worked with.</param>
         /// <param name="remoteName">The name of the <see cref="Remote"/> to fetch from.</param>
-        /// <param name="progress">The <see cref = "FetchProgress" /> datastructure where the progress of the fetch is reported.</param>
         /// <param name="tagFetchMode">Optional parameter indicating what tags to download.</param>
         /// <param name="onProgress">Progress callback. Corresponds to libgit2 progress callback.</param>
         /// <param name="onCompletion">Completion callback. Corresponds to libgit2 completion callback.</param>
         /// <param name="onUpdateTips">UpdateTips callback. Corresponds to libgit2 update_tips callback.</param>
-        public static void Fetch(this IRepository repository, string remoteName, FetchProgress progress = null,
+        /// <param name="onTransferProgress">Callback method that transfer progress will be reported through.
+        ///   Reports the client's state regarding the received and processed (bytes, objects) from the server.</param>
+        public static void Fetch(this IRepository repository, string remoteName,
             TagFetchMode tagFetchMode = TagFetchMode.Auto,
             ProgressHandler onProgress = null,
             CompletionHandler onCompletion = null,
-            UpdateTipsHandler onUpdateTips = null)
+            UpdateTipsHandler onUpdateTips = null,
+            TransferProgressHandler onTransferProgress = null)
         {
             Ensure.ArgumentNotNull(repository, "repository");
             Ensure.ArgumentNotNullOrEmptyString(remoteName, "remoteName");
 
             Remote remote = repository.Remotes.RemoteForName(remoteName, true);
-            remote.Fetch(progress, tagFetchMode, onProgress, onCompletion, onUpdateTips);
+            remote.Fetch(tagFetchMode, onProgress, onCompletion, onUpdateTips, onTransferProgress);
         }
 
         private static Signature BuildSignatureFromGlobalConfiguration(IRepository repository, DateTimeOffset now)

LibGit2Sharp/TransferCallbacks.cs

@@ -0,0 +1,54 @@
+using System;
+using LibGit2Sharp.Core;
+using LibGit2Sharp.Handlers;
+
+namespace LibGit2Sharp
+{
+    /// <summary>
+    ///   Class to handle the mapping between libgit2 git_transfer_progress_callback function and 
+    ///   a corresponding <see cref = "TransferProgressHandler" />. Generates a delegate that 
+    ///   wraps the <see cref = "TransferProgressHandler" /> delegate with a delegate that matches
+    ///   the git_transfer_progress_callback signature.
+    /// </summary>
+    internal class TransferCallbacks
+    {
+        /// <summary>
+        ///   Managed delegate to be called in response to a git_transfer_progress_callback callback from libgit2.
+        /// </summary>
+        private TransferProgressHandler onTransferProgress;
+
+        /// <summary>
+        ///   Constructor to set up the native callback given managed delegate.
+        /// </summary>
+        /// <param name="onTransferProgress">The <see cref="TransferProgressHandler"/> delegate that the git_transfer_progress_callback will call.</param>
+        private TransferCallbacks(TransferProgressHandler onTransferProgress)
+        {
+            this.onTransferProgress = onTransferProgress;
+        }
+
+        /// <summary>
+        ///   Generates a delegate that matches the native git_transfer_progress_callback function's signature and wraps the <see cref = "TransferProgressHandler" /> delegate.
+        /// </summary>
+        /// <param name="onTransferProgress">The <see cref = "TransferProgressHandler" /> delegate to call in responde to a the native git_transfer_progress_callback callback.</param>
+        /// <returns>A delegate method with a signature that matches git_transfer_progress_callback.</returns>
+        internal static NativeMethods.git_transfer_progress_callback GenerateCallback(TransferProgressHandler onTransferProgress)
+        {
+            if (onTransferProgress == null)
+            {
+                return null;
+            }
+
+            return new TransferCallbacks(onTransferProgress).OnGitTransferProgress;
+        }
+
+        /// <summary>
+        ///   The delegate with the signature that matches the native git_transfer_progress_callback function's signature.
+        /// </summary>
+        /// <param name="progress"><see cref = "GitTransferProgress" /> structure containing progress information.</param>
+        /// <param name="payload">Payload data.</param>
+        private void OnGitTransferProgress(ref GitTransferProgress progress, IntPtr payload)
+        {
+            onTransferProgress(new TransferProgress(progress));
+        }
+    }
+}

LibGit2Sharp/TransferProgress.cs

@@ -0,0 +1,71 @@
+using System;
+using LibGit2Sharp.Core;
+
+namespace LibGit2Sharp
+{
+    /// <summary>
+    ///   Expose progress values from a fetch operation.
+    /// </summary>
+    public class TransferProgress
+    {
+        private GitTransferProgress gitTransferProgress;
+
+        /// <summary>
+        ///   Empty constructor.
+        /// </summary>
+        protected TransferProgress()
+        { }
+
+        /// <summary>
+        ///   Constructor.
+        /// </summary>
+        internal TransferProgress(GitTransferProgress gitTransferProgress)
+        {
+            this.gitTransferProgress = gitTransferProgress;
+        }
+
+        /// <summary>
+        ///   Total number of objects.
+        /// </summary>
+        public virtual int TotalObjects
+        {
+            get
+            {
+                return (int) gitTransferProgress.total_objects;
+            }
+        }
+
+        /// <summary>
+        ///   Number of objects indexed.
+        /// </summary>
+        public virtual int IndexedObjects
+        {
+            get
+            {
+                return (int) gitTransferProgress.indexed_objects;
+            }
+        }
+
+        /// <summary>
+        ///   Number of objects received.
+        /// </summary>
+        public virtual int ReceivedObjects
+        {
+            get
+            {
+                return (int) gitTransferProgress.received_objects;
+            }
+        }
+
+        /// <summary>
+        ///   Number of bytes received.
+        /// </summary>
+        public virtual long ReceivedBytes
+        {
+            get
+            {
+                return (long) gitTransferProgress.received_bytes;
+            }
+        }
+    }
+}