Use chatId from URL rather than from payload for chats (#700)

### Motivation and Context
The verify access to a chat, we use HandleRequest() with the chatId
provided. Currently, we get this from the payload, which can differ from
the chatId from the URL, which opens us to a security problem where a
user could inject an arbitrary chatId in the payload, which doesn't
match what's in the URL.

### Description
- Use chatId from URL and only from URL
- Add integrations test to validate this

### Contribution Checklist
- [ ] The code builds clean without any errors or warnings
- [ ] The PR follows the [Contribution
Guidelines](https://github.com/microsoft/chat-copilot/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/chat-copilot/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [ ] All unit tests pass, and I have added new tests where possible
- [ ] I didn't break anyone 😄

integration-tests/ChatTests.cs

@@ -0,0 +1,50 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Net.Http.Json;
+using System.Text.Json;
+using CopilotChat.WebApi.Models.Request;
+using CopilotChat.WebApi.Models.Response;
+using Xunit;
+using static CopilotChat.WebApi.Models.Storage.CopilotChatMessage;
+
+namespace ChatCopilotIntegrationTests;
+
+public class ChatTests : ChatCopilotIntegrationTest
+{
+    [Fact]
+    public async void ChatMessagePostSucceedsWithValidInput()
+    {
+        await this.SetUpAuth();
+
+        // Create chat session
+        var createChatParams = new CreateChatParameters() { Title = nameof(ChatMessagePostSucceedsWithValidInput) };
+        HttpResponseMessage response = await this._httpClient.PostAsJsonAsync("chats", createChatParams);
+        response.EnsureSuccessStatusCode();
+
+        var contentStream = await response.Content.ReadAsStreamAsync();
+        var createChatResponse = await JsonSerializer.DeserializeAsync<CreateChatResponse>(contentStream, new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+        Assert.NotNull(createChatResponse);
+
+        // Ask something to the bot
+        var ask = new Ask
+        {
+            Input = "Who is Satya Nadella?",
+            Variables = new KeyValuePair<string, string>[] { new("MessageType", ChatMessageType.Message.ToString()) }
+        };
+        response = await this._httpClient.PostAsJsonAsync($"chats/{createChatResponse.ChatSession.Id}/messages", ask);
+        response.EnsureSuccessStatusCode();
+
+        contentStream = await response.Content.ReadAsStreamAsync();
+        var askResult = await JsonSerializer.DeserializeAsync<AskResult>(contentStream, new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+        Assert.NotNull(askResult);
+        Assert.False(string.IsNullOrEmpty(askResult.Value));
+
+
+        // Clean up
+        response = await this._httpClient.DeleteAsync($"chats/{createChatResponse.ChatSession.Id}");
+        response.EnsureSuccessStatusCode();
+    }
+}
+

webapi/Controllers/ChatController.cs

@@ -99,7 +99,6 @@ public async Task<IActionResult> ChatAsync(
         [FromServices] IKernel kernel,
         [FromServices] IHubContext<MessageRelayHub> messageRelayHubContext,
         [FromServices] CopilotChatPlanner planner,
-        [FromServices] AskConverter askConverter,
         [FromServices] ChatSessionRepository chatSessionRepository,
         [FromServices] ChatParticipantRepository chatParticipantRepository,
         [FromServices] IAuthInfo authInfo,
@@ -108,7 +107,7 @@ public async Task<IActionResult> ChatAsync(
     {
         this._logger.LogDebug("Chat message received.");
 
-        return await this.HandleRequest(ChatFunctionName, kernel, messageRelayHubContext, planner, askConverter, chatSessionRepository, chatParticipantRepository, authInfo, ask, chatId.ToString());
+        return await this.HandleRequest(ChatFunctionName, kernel, messageRelayHubContext, planner, chatSessionRepository, chatParticipantRepository, authInfo, ask, chatId.ToString());
     }
 
     /// <summary>
@@ -135,7 +134,6 @@ public async Task<IActionResult> ProcessPlanAsync(
         [FromServices] IKernel kernel,
         [FromServices] IHubContext<MessageRelayHub> messageRelayHubContext,
         [FromServices] CopilotChatPlanner planner,
-        [FromServices] AskConverter askConverter,
         [FromServices] ChatSessionRepository chatSessionRepository,
         [FromServices] ChatParticipantRepository chatParticipantRepository,
         [FromServices] IAuthInfo authInfo,
@@ -144,7 +142,7 @@ public async Task<IActionResult> ProcessPlanAsync(
     {
         this._logger.LogDebug("plan request received.");
 
-        return await this.HandleRequest(ProcessPlanFunctionName, kernel, messageRelayHubContext, planner, askConverter, chatSessionRepository, chatParticipantRepository, authInfo, ask, chatId.ToString());
+        return await this.HandleRequest(ProcessPlanFunctionName, kernel, messageRelayHubContext, planner, chatSessionRepository, chatParticipantRepository, authInfo, ask, chatId.ToString());
     }
 
     /// <summary>
@@ -166,15 +164,14 @@ private async Task<IActionResult> HandleRequest(
        IKernel kernel,
        IHubContext<MessageRelayHub> messageRelayHubContext,
        CopilotChatPlanner planner,
-       AskConverter askConverter,
        ChatSessionRepository chatSessionRepository,
        ChatParticipantRepository chatParticipantRepository,
        IAuthInfo authInfo,
        Ask ask,
        string chatId)
     {
         // Put ask's variables in the context we will use.
-        var contextVariables = askConverter.GetContextVariables(ask);
+        var contextVariables = GetContextVariables(ask, authInfo, chatId);
 
         // Verify that the chat exists and that the user has access to it.
         ChatSession? chat = null;
@@ -415,6 +412,25 @@ await planner.Kernel.ImportOpenAIPluginFunctionsAsync(
         return;
     }
 
+    private static ContextVariables GetContextVariables(Ask ask, IAuthInfo authInfo, string chatId)
+    {
+        const string UserIdKey = "userId";
+        const string UserNameKey = "userName";
+        const string ChatIdKey = "chatId";
+
+        var contextVariables = new ContextVariables(ask.Input);
+        foreach (var variable in ask.Variables)
+        {
+            contextVariables.Set(variable.Key, variable.Value);
+        }
+
+        contextVariables.Set(UserIdKey, authInfo.UserId);
+        contextVariables.Set(UserNameKey, authInfo.Name);
+        contextVariables.Set(ChatIdKey, chatId);
+
+        return contextVariables;
+    }
+
     /// <summary>
     /// Dispose of the object.
     /// </summary>

webapi/Extensions/ServiceExtensions.cs

@@ -81,11 +81,6 @@ internal static void AddOptions<TOptions>(this IServiceCollection services, ICon
             .PostConfigure(TrimStringProperties);
     }
 
-    internal static IServiceCollection AddUtilities(this IServiceCollection services)
-    {
-        return services.AddScoped<AskConverter>();
-    }
-
     internal static IServiceCollection AddPlugins(this IServiceCollection services, IConfiguration configuration)
     {
         var plugins = configuration.GetSection("Plugins").Get<List<Plugin>>() ?? new List<Plugin>();

webapi/Program.cs

@@ -45,7 +45,6 @@ public static async Task Main(string[] args)
             .AddOptions(builder.Configuration)
             .AddPersistentChatStore()
             .AddPlugins(builder.Configuration)
-            .AddUtilities()
             .AddChatCopilotAuthentication(builder.Configuration)
             .AddChatCopilotAuthorization();