feat(IFileSystemApi): progress report when adding

src/CoreApi/AddFileOptions.cs

@@ -93,5 +93,10 @@ public class AddFileOptions
         /// </remarks>
         /// <seealso cref="IKeyApi"/>
         public string ProtectionKey { get; set; }
+
+        /// <summary>
+        ///   Used to report the progress of a file transfer.
+        /// </summary>
+        public IProgress<TransferProgress> Progress { get; set; }
     }
 }

src/CoreApi/TransferProgress.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Ipfs.CoreApi
+{
+    /// <summary>
+    ///   Reports the <see cref="IProgress{T}">progress</see> of
+    ///   a transfer operation.
+    /// </summary>
+    public class TransferProgress
+    {
+        /// <summary>
+        ///   The name of the item being trasfered.
+        /// </summary>
+        /// <value>
+        ///   Typically, a relative file path.
+        /// </value>
+        public string Name;
+
+        /// <summary>
+        ///   The cumuative number of bytes transfered for
+        ///   the <see cref="Name"/>.
+        /// </summary>
+        public ulong Bytes;
+    }
+}

test/CoreApi/AddFileOptionsTest.cs

@@ -1,4 +1,5 @@
-using System.Linq;
+using System;
+using System.Linq;
 using System.Text;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
@@ -19,6 +20,7 @@ public void Defaults()
             Assert.AreEqual(false, options.RawLeaves);
             Assert.AreEqual(false, options.Trickle);
             Assert.AreEqual(false, options.Wrap);
+            Assert.IsNull(options.Progress);
         }
 
         [TestMethod]
@@ -31,6 +33,7 @@ public void Setting()
                 Hash = "sha2-512",
                 OnlyHash = true,
                 RawLeaves = true,
+                Progress = new Progress<TransferProgress>(),
                 Trickle = true,
                 Wrap = true
             };
@@ -42,6 +45,8 @@ public void Setting()
             Assert.AreEqual(true, options.RawLeaves);
             Assert.AreEqual(true, options.Trickle);
             Assert.AreEqual(true, options.Wrap);
+            Assert.IsNotNull(options.Progress);
         }
+
     }
 }