Implement MultipartBody filename

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- `MultipartBody` now supports an optional `fileName` parameter to specify the file name of the part. (https://github.com/microsoft/kiota-abstractions-dotnet/issues/212)
+
 ## [1.8.0] - 2024-03-18
 
 ### Added

Microsoft.Kiota.Abstractions.Tests/MultipartBodyTests.cs

@@ -0,0 +1,68 @@
+using Microsoft.Kiota.Abstractions.Serialization;
+using Moq;
+using Xunit;
+
+namespace Microsoft.Kiota.Abstractions.Tests;
+
+public class MultipartBodyTests
+{
+    [Fact]
+    public void KeepsFilename()
+    {
+        var writerMock = new Mock<ISerializationWriter>();
+        var requestAdapterMock = new Mock<IRequestAdapter>();
+        var serializationFactoryMock = new Mock<ISerializationWriterFactory>();
+
+        var body = new MultipartBody();
+
+        requestAdapterMock
+            .Setup(r => r.SerializationWriterFactory)
+            .Returns(serializationFactoryMock.Object);
+
+        body.RequestAdapter = requestAdapterMock.Object;
+
+        writerMock.Setup(w => w.WriteStringValue("", "--" + body.Boundary));
+        writerMock.Setup(w => w.WriteStringValue("Content-Type", "application/json"));
+        writerMock.Setup(w => w.WriteStringValue("Content-Disposition", "form-data; name=\"file\"; filename=\"file.json\""));
+        writerMock.Setup(w => w.WriteStringValue("", "fileContent"));
+        writerMock.Setup(w => w.WriteStringValue("", ""));
+        writerMock.Setup(w => w.WriteStringValue("", "--" + body.Boundary + "--"));
+
+        body.AddOrReplacePart("file", "application/json", "fileContent", "file.json");
+        body.Serialize(writerMock.Object);
+
+        writerMock.VerifyAll();
+        requestAdapterMock.VerifyAll();
+        serializationFactoryMock.VerifyAll();
+    }
+
+    [Fact]
+    public void WorksWithoutFilename()
+    {
+        var writerMock = new Mock<ISerializationWriter>();
+        var requestAdapterMock = new Mock<IRequestAdapter>();
+        var serializationFactoryMock = new Mock<ISerializationWriterFactory>();
+
+        var body = new MultipartBody();
+
+        requestAdapterMock
+            .Setup(r => r.SerializationWriterFactory)
+            .Returns(serializationFactoryMock.Object);
+
+        body.RequestAdapter = requestAdapterMock.Object;
+
+        writerMock.Setup(w => w.WriteStringValue("", "--" + body.Boundary));
+        writerMock.Setup(w => w.WriteStringValue("Content-Type", "application/json"));
+        writerMock.Setup(w => w.WriteStringValue("Content-Disposition", "form-data; name=\"file\""));
+        writerMock.Setup(w => w.WriteStringValue("", "fileContent"));
+        writerMock.Setup(w => w.WriteStringValue("", ""));
+        writerMock.Setup(w => w.WriteStringValue("", "--" + body.Boundary + "--"));
+
+        body.AddOrReplacePart("file", "application/json", "fileContent");
+        body.Serialize(writerMock.Object);
+
+        writerMock.VerifyAll();
+        requestAdapterMock.VerifyAll();
+        serializationFactoryMock.VerifyAll();
+    }
+}

src/Microsoft.Kiota.Abstractions.csproj

@@ -14,7 +14,7 @@
     <PackageProjectUrl>https://aka.ms/kiota/docs</PackageProjectUrl>
     <EmbedUntrackedSources>true</EmbedUntrackedSources>
     <Deterministic>true</Deterministic>
-    <VersionPrefix>1.8.0</VersionPrefix>
+    <VersionPrefix>1.8.1</VersionPrefix>
     <VersionSuffix></VersionSuffix>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <SignAssembly>false</SignAssembly>

src/MultipartBody.cs

@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Text;
 using Microsoft.Kiota.Abstractions.Extensions;
 using Microsoft.Kiota.Abstractions.Serialization;
 
@@ -32,7 +33,8 @@ public class MultipartBody : IParsable
     /// <param name="partName">The name of the part.</param>
     /// <param name="contentType">The content type of the part.</param>
     /// <param name="partValue">The value of the part.</param>
-    public void AddOrReplacePart<T>(string partName, string contentType, T partValue)
+    /// <param name="fileName">An optional file name for the part.</param>
+    public void AddOrReplacePart<T>(string partName, string contentType, T partValue, string? fileName = null)
     {
         if(string.IsNullOrEmpty(partName))
         {
@@ -46,7 +48,7 @@ public void AddOrReplacePart<T>(string partName, string contentType, T partValue
         {
             throw new ArgumentNullException(nameof(partValue));
         }
-        var value = new Tuple<string, object>(contentType, partValue);
+        var value = new Part(partName, partValue, contentType, fileName);
         if(!_parts.TryAdd(partName, value))
         {
             _parts[partName] = value;
@@ -66,7 +68,10 @@ public void AddOrReplacePart<T>(string partName, string contentType, T partValue
         }
         if(_parts.TryGetValue(partName, out var value))
         {
-            return (T)value.Item2;
+            if(value == null)
+                return default;
+
+            return (T)value.Content;
         }
         return default;
     }
@@ -83,7 +88,8 @@ public bool RemovePart(string partName)
         }
         return _parts.Remove(partName);
     }
-    private readonly Dictionary<string, Tuple<string, object>> _parts = new Dictionary<string, Tuple<string, object>>(StringComparer.OrdinalIgnoreCase);
+
+    private readonly Dictionary<string, Part> _parts = new Dictionary<string, Part>(StringComparer.OrdinalIgnoreCase);
     /// <inheritdoc />
     public IDictionary<string, Action<IParseNode>> GetFieldDeserializers() => throw new NotImplementedException();
     /// <inheritdoc />
@@ -102,7 +108,8 @@ public void Serialize(ISerializationWriter writer)
             throw new InvalidOperationException("No parts to serialize");
         }
         var first = true;
-        foreach(var part in _parts)
+        var contentDispositionBuilder = new StringBuilder();
+        foreach(var part in _parts.Values)
         {
             try
             {
@@ -112,12 +119,26 @@ public void Serialize(ISerializationWriter writer)
                     AddNewLine(writer);
 
                 writer.WriteStringValue(string.Empty, $"--{Boundary}");
-                writer.WriteStringValue("Content-Type", $"{part.Value.Item1}");
-                writer.WriteStringValue("Content-Disposition", $"form-data; name=\"{part.Key}\"");
+                writer.WriteStringValue("Content-Type", part.ContentType);
+
+                contentDispositionBuilder.Clear();
+                contentDispositionBuilder.Append("form-data; name=\"");
+                contentDispositionBuilder.Append(part.Name);
+                contentDispositionBuilder.Append("\"");
+
+                if (part.FileName != null)
+                {
+                    contentDispositionBuilder.Append("; filename=\"");
+                    contentDispositionBuilder.Append(part.FileName);
+                    contentDispositionBuilder.Append("\"");
+                }
+
+                writer.WriteStringValue("Content-Disposition", contentDispositionBuilder.ToString());
+
                 AddNewLine(writer);
-                if(part.Value.Item2 is IParsable parsable)
+                if(part.Content is IParsable parsable)
                 {
-                    using var partWriter = RequestAdapter.SerializationWriterFactory.GetSerializationWriter(part.Value.Item1);
+                    using var partWriter = RequestAdapter.SerializationWriterFactory.GetSerializationWriter(part.ContentType);
                     partWriter.WriteObjectValue(string.Empty, parsable);
                     using var partContent = partWriter.GetSerializedContent();
                     if(partContent.CanSeek)
@@ -126,34 +147,34 @@ public void Serialize(ISerializationWriter writer)
                     partContent.CopyTo(ms);
                     writer.WriteByteArrayValue(string.Empty, ms.ToArray());
                 }
-                else if(part.Value.Item2 is string currentString)
+                else if(part.Content is string currentString)
                 {
                     writer.WriteStringValue(string.Empty, currentString);
                 }
-                else if(part.Value.Item2 is MemoryStream originalMemoryStream)
+                else if(part.Content is MemoryStream originalMemoryStream)
                 {
                     writer.WriteByteArrayValue(string.Empty, originalMemoryStream.ToArray());
                 }
-                else if(part.Value.Item2 is Stream currentStream)
+                else if(part.Content is Stream currentStream)
                 {
                     if(currentStream.CanSeek)
                         currentStream.Seek(0, SeekOrigin.Begin);
                     using var ms = new MemoryStream();
                     currentStream.CopyTo(ms);
                     writer.WriteByteArrayValue(string.Empty, ms.ToArray());
                 }
-                else if(part.Value.Item2 is byte[] currentBinary)
+                else if(part.Content is byte[] currentBinary)
                 {
                     writer.WriteByteArrayValue(string.Empty, currentBinary);
                 }
                 else
                 {
-                    throw new InvalidOperationException($"Unsupported type {part.Value.Item2.GetType().Name} for part {part.Key}");
+                    throw new InvalidOperationException($"Unsupported type {part.Content.GetType().Name} for part {part.Name}");
                 }
             }
-            catch(InvalidOperationException) when(part.Value.Item2 is byte[] currentBinary)
+            catch(InvalidOperationException) when(part?.Content is byte[] currentBinary)
             { // binary payload
-                writer.WriteByteArrayValue(part.Key, currentBinary);
+                writer.WriteByteArrayValue(part.Name, currentBinary);
             }
         }
         AddNewLine(writer);
@@ -163,4 +184,20 @@ private void AddNewLine(ISerializationWriter writer)
     {
         writer.WriteStringValue(string.Empty, string.Empty);
     }
+
+    private class Part
+    {
+        public Part(string name, object content, string contentType, string? fileName)
+        {
+            this.Name = name;
+            this.Content = content;
+            this.ContentType = contentType;
+            this.FileName = fileName;
+        }
+
+        public string Name { get; }
+        public object Content { get; }
+        public string ContentType { get; }
+        public string? FileName { get; }
+    }
 }