Adding file support

.devcontainer/devcontainer.json

@@ -6,7 +6,9 @@
 	"image": "mcr.microsoft.com/devcontainers/base:jammy",
 	"features": {
 		"ghcr.io/devcontainers/features/dotnet:2": {},
-		"ghcr.io/devcontainers/features/node:1": {}
+		"ghcr.io/devcontainers/features/node:1": {},
+		"ghcr.io/devcontainers/features/python": "3.12",
+		"ghcr.io/devcontainers/features/azure-cli": "latest"
 	}
 
 	// Features to add to the dev container. More info: https://containers.dev/features.

.github/CODEOWNERS

@@ -1,2 +1,3 @@
 * @dargilco
-* @glecaros
+* @glecaros
+* @rohit-ganguly

samples/backend/csharp/ChatProtocolBackend.csproj

@@ -10,7 +10,7 @@
     <PackageReference Include="Azure.Identity" Version="1.11.4" />
     <PackageReference Include="Azure.Security.KeyVault.Secrets" Version="4.6.0" />  
     <PackageReference Include="Microsoft.SemanticKernel" Version="1.7.1" />
-    <PackageReference Include="System.Text.Json" Version="8.0.3" />
+    <PackageReference Include="System.Text.Json" Version="8.0.4" />
   </ItemGroup>
 
 </Project>

samples/backend/csharp/Controllers/ChatController.cs

@@ -6,11 +6,12 @@
 
 using Backend.Interfaces;
 using Backend.Model;
+using System.Text.RegularExpressions;
 
 namespace Backend.Controllers;
 
 [ApiController, Route("api/[controller]")]
-public class ChatController : ControllerBase
+public partial class ChatController : ControllerBase
 {
     private readonly ISemanticKernelApp _semanticKernelApp;
 
@@ -19,6 +20,79 @@ public ChatController(ISemanticKernelApp semanticKernelApp)
         _semanticKernelApp = semanticKernelApp;
     }
 
+    [GeneratedRegex(@"messages\[(\d+)\]\.files\[(\d+)\]")]
+    private static partial Regex MessageFilesRegex();
+
+    private (int MessageIndex, int FileIndex, IFormFile File) GetPosition(IFormFile formFile)
+    {
+        var match = MessageFilesRegex().Match(formFile.Name);
+        if (match.Success && int.TryParse(match.Groups[1].ValueSpan, out var messageIndex) && int.TryParse(match.Groups[2].ValueSpan, out var fileIndex))
+        {
+            return (messageIndex, fileIndex, formFile);
+        }
+
+        throw new ArgumentException("Malformed multipart request: Invalid file name.");
+    }
+
+    private async Task<AIChatRequest> RequestFromMultipart(IFormFileCollection formFiles)
+    {
+        using var jsonFileStream = formFiles
+            .First(f => f.Name == "json")
+            .OpenReadStream();
+        if (jsonFileStream is null)
+        {
+            throw new Exception("Malformed multipart request: Missing json part.");
+        }
+
+        var request = await JsonSerializer.DeserializeAsync<AIChatRequest>(jsonFileStream) ??
+            throw new Exception("Malformed multipart request: Invalid json part.");
+        foreach (var (messageIndex, fileIndex, file) in formFiles.Where(f => f.Name != "json").Select(GetPosition).OrderBy(p => p.MessageIndex).ThenBy(p => p.FileIndex))
+        {
+            if (request.Messages.Count <= messageIndex)
+            {
+                throw new Exception("Malformed multipart request: Invalid message index.");
+            }
+
+            var message = request.Messages[messageIndex];
+            message.Files ??= new List<AIChatFile>();
+            if (message.Files.Count != fileIndex)
+            {
+                throw new Exception("Malformed multipart request: Invalid file index.");
+            }
+
+            using var fileStream = file.OpenReadStream();
+            var fileData = await BinaryData.FromStreamAsync(fileStream);
+            message.Files.Add(new AIChatFile
+            {
+                ContentType = file.ContentType,
+                Data = fileData
+            });
+
+        }
+        return request;
+    }
+
+    [HttpPost]
+    [Consumes("multipart/form-data")]
+    public async Task<IActionResult> ProcessMessage(IFormFileCollection files)
+    {
+        try
+        {
+            var request = await RequestFromMultipart(files);
+            var session = request.SessionState switch
+            {
+                Guid sessionId => await _semanticKernelApp.GetSession(sessionId),
+                _ => await _semanticKernelApp.CreateSession(Guid.NewGuid())
+            };
+
+            return Ok(await session.ProcessRequest(request));
+        }
+        catch (Exception e)
+        {
+            return BadRequest(e.Message);
+        }
+    }
+
     [HttpPost]
     [Consumes("application/json")]
     public async Task<IActionResult> ProcessMessage(AIChatRequest request)

samples/backend/csharp/Model/AIChatFile.cs

@@ -0,0 +1,15 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System.Text.Json.Serialization;
+
+namespace Backend.Model;
+
+public struct AIChatFile
+{
+    [JsonPropertyName("contentType")]
+    public string ContentType { get; set; }
+
+    [JsonPropertyName("data")]
+    public BinaryData Data { get; set; }
+}

samples/backend/csharp/Model/AIChatMessage.cs

@@ -15,5 +15,8 @@ public struct AIChatMessage
 
     [JsonPropertyName("context")]
     public BinaryData? Context { get; set; }
+
+    [JsonPropertyName("files")]
+    public IList<AIChatFile>? Files { get; set; }
 }
 

samples/backend/csharp/Services/SemanticKernelApp.cs

@@ -47,13 +47,15 @@ internal class SemanticKernelSession : ISemanticKernelSession
 {
     private readonly Kernel _kernel;
     private readonly IStateStore<string> _stateStore;
+    private readonly KernelFunction _chatFunction;
 
     public Guid Id { get; private set; }
 
     internal SemanticKernelSession(Kernel kernel, IStateStore<string> stateStore, Guid sessionId)
     {
         _kernel = kernel;
         _stateStore = stateStore;
+        _chatFunction = _kernel.CreateFunctionFromPrompt(prompt);
         Id = sessionId;
     }
 
@@ -66,16 +68,16 @@ ChatBot can have a conversation with you about any topic.
         ChatBot:";
 
     public async Task<AIChatCompletion> ProcessRequest(AIChatRequest message)
-    {        
-        var chatFunction = _kernel.CreateFunctionFromPrompt(prompt);
+    {
         var userInput = message.Messages.Last();
         string history = await _stateStore.GetStateAsync(Id) ?? "";
+        /* TODO: Add support for text+image content */
         var arguments = new KernelArguments()
         {
             ["history"] = history,
             ["userInput"] = userInput.Content,
         };
-        var botResponse = await chatFunction.InvokeAsync(_kernel, arguments);
+        var botResponse = await _chatFunction.InvokeAsync(_kernel, arguments);
         var updatedHistory = $"{history}\nUser: {userInput.Content}\nChatBot: {botResponse}";
         await _stateStore.SetStateAsync(Id, updatedHistory);
         return new AIChatCompletion(Message: new AIChatMessage
@@ -89,16 +91,15 @@ public async Task<AIChatCompletion> ProcessRequest(AIChatRequest message)
     }
 
     public async IAsyncEnumerable<AIChatCompletionDelta> ProcessStreamingRequest(AIChatRequest message)
-    {        
-        var chatFunction = _kernel.CreateFunctionFromPrompt(prompt);
+    {
         var userInput = message.Messages.Last();
         string history = await _stateStore.GetStateAsync(Id) ?? "";
         var arguments = new KernelArguments()
         {
             ["history"] = history,
             ["userInput"] = userInput.Content,
         };
-        var streamedBotResponse = chatFunction.InvokeStreamingAsync(_kernel, arguments);
+        var streamedBotResponse = _chatFunction.InvokeStreamingAsync(_kernel, arguments);
         StringBuilder response = new();
         await foreach (var botResponse in streamedBotResponse)
         {

samples/backend/js/expressjs/.gitignore

@@ -1 +1,2 @@
+.env
 dist