added a chat service to handle chat api access and caching

src/web/Client/Features/Chat/ChatService.cs

@@ -0,0 +1,136 @@
+using Jordnaer.Client.Models;
+using System.Net;
+using Jordnaer.Shared;
+using Microsoft.Extensions.Caching.Memory;
+using MudBlazor;
+using Refit;
+
+namespace Jordnaer.Client.Features.Chat;
+
+public interface IChatService
+{
+    ValueTask<List<ChatDto>> GetChats(string userId);
+    ValueTask<List<ChatMessageDto>> GetChatMessages(Guid chatId);
+    ValueTask StartChat(ChatDto chat);
+    ValueTask SendMessage(ChatMessageDto message);
+}
+
+public class ChatService : IChatService
+{
+    private readonly IMemoryCache _cache;
+    private readonly IChatClient _chatClient;
+    private readonly ISnackbar _snackbar;
+
+    public ChatService(IMemoryCache cache, IChatClient chatClient, ISnackbar snackbar)
+    {
+        _cache = cache;
+        _chatClient = chatClient;
+        _snackbar = snackbar;
+    }
+
+    public async ValueTask<List<ChatDto>> GetChats(string userId)
+    {
+        string key = $"{userId}-chats";
+        bool cacheWasEmpty = false;
+        var cachedChats = await _cache.GetOrCreateAsync(key, async entry =>
+        {
+            cacheWasEmpty = true;
+            entry.AbsoluteExpirationRelativeToNow = TimeSpan.FromDays(7);
+
+            return HandleApiResponse(await _chatClient.GetChats(userId));
+        });
+
+        if (cacheWasEmpty)
+        {
+            return cachedChats ?? new List<ChatDto>();
+        }
+
+        var newChats = HandleApiResponse(await _chatClient.GetChats(userId, cachedChats?.Count ?? 0));
+        if (cachedChats is null)
+        {
+            return newChats;
+        }
+
+        cachedChats.AddRange(newChats);
+
+        return cachedChats;
+    }
+
+    public async ValueTask<List<ChatMessageDto>> GetChatMessages(Guid chatId)
+    {
+        string key = $"{chatId}-chatmessages";
+        bool cacheWasEmpty = false;
+        var cachedMessages = await _cache.GetOrCreateAsync(key, async entry =>
+        {
+            cacheWasEmpty = true;
+
+            entry.AbsoluteExpirationRelativeToNow = TimeSpan.FromDays(7);
+
+            return HandleApiResponse(await _chatClient.GetChatMessages(chatId));
+        });
+
+        if (cacheWasEmpty)
+        {
+            return cachedMessages ?? new List<ChatMessageDto>();
+        }
+        var newMessages = HandleApiResponse(await _chatClient.GetChatMessages(chatId, cachedMessages?.Count ?? 0));
+        if (cachedMessages is null)
+        {
+            return newMessages;
+        }
+
+        cachedMessages.AddRange(newMessages);
+
+        return cachedMessages;
+    }
+
+    public async ValueTask StartChat(ChatDto chat) => HandleApiResponse(await _chatClient.StartChat(chat));
+
+    public async ValueTask SendMessage(ChatMessageDto message) => HandleApiResponse(await _chatClient.SendMessage(message));
+
+    /// <summary>
+    /// Checks the <c>StatusCode</c> of the <see cref="IApiResponse"/> and shows a popup if <c>IsSuccessStatusCode</c> is false..
+    /// </summary>
+    /// <typeparam name="T"></typeparam>
+    /// <param name="response"></param>
+    private T HandleApiResponse<T>(IApiResponse<T> response) where T : new()
+    {
+        switch (response.StatusCode)
+        {
+            case { } when response.IsSuccessStatusCode:
+                return response.Content!;
+
+            case HttpStatusCode.TooManyRequests:
+                _snackbar.Add(ErrorMessages.High_Load, Severity.Info);
+                break;
+
+            default:
+                _snackbar.Add(ErrorMessages.Something_Went_Wrong_Refresh, Severity.Warning);
+                break;
+        }
+
+        return new T();
+    }
+
+
+    /// <summary>
+    /// Checks the <c>StatusCode</c> of the <see cref="IApiResponse"/> and shows a popup if <c>IsSuccessStatusCode</c> is false..
+    /// </summary>
+    /// <param name="response"></param>
+    private void HandleApiResponse(IApiResponse response)
+    {
+        switch (response.StatusCode)
+        {
+            case { } when response.IsSuccessStatusCode:
+                return;
+
+            case HttpStatusCode.TooManyRequests:
+                _snackbar.Add(ErrorMessages.High_Load, Severity.Info);
+                break;
+
+            default:
+                _snackbar.Add(ErrorMessages.Something_Went_Wrong_Refresh, Severity.Warning);
+                break;
+        }
+    }
+}

src/web/Client/Features/Chat/IChatClient.cs

@@ -9,7 +9,7 @@ public interface IChatClient
     Task<IApiResponse<List<ChatDto>>> GetChats(string userId, int skip = 0, int take = int.MaxValue);
 
     [Get($"/api/chat/{MessagingConstants.GetChatMessages}/{{chatId}}")]
-    Task<IApiResponse<List<ChatMessageDto>>> GetChatMessages(Guid chatId, int skip = 0, int take = 15);
+    Task<IApiResponse<List<ChatMessageDto>>> GetChatMessages(Guid chatId, int skip = 0, int take = int.MaxValue);
 
     [Post($"/api/chat/{MessagingConstants.StartChat}")]
     Task<IApiResponse> StartChat([Body] ChatDto chat);

src/web/Client/Features/Chat/LargeChatComponent.razor

@@ -1,14 +1,7 @@
-@using System.Globalization
-@using System.Linq.Expressions
-@using System.Security.Claims
-@using MassTransit
-@using Microsoft.VisualBasic.CompilerServices
-@inject IChatClient ChatClient
+@inject IChatService ChatService
 @inject IProfileCache ProfileCache
-@inject AuthenticationStateProvider AuthenticationStateProvider
 @inject ISnackbar Snackbar
 @inject IJSRuntime JsRuntime
-@inject IScrollManager ScrollManager
 @attribute [Authorize]
 
 @if (_currentUser is null)
@@ -26,11 +19,6 @@
                 </MudListSubheader>
                 @foreach (var chat in _chats)
                 {
-                    @* TODO
-                - Fetch all messages now found in cache
-                - Fetch all chats not found in cache
-                - Virtualize chat (load at the top with scroll listener)
-                *@
                     <MudListItem OnClick="@(() => SelectChat(chat))" Dense="true" Class="chat-selector">
 
                         <MudAvatar Size="Size.Large" Class="mr-3">
@@ -104,7 +92,6 @@
     private bool _isActiveChatPublished = true;
     private bool _isLoading = true;
 
-
     // TODO: Select currently displayed chat using this, when we update to dotnet 8
     [SupplyParameterFromQuery]
     public Guid? ChatId { get; set; }
@@ -120,21 +107,7 @@
 
         _currentUserSlim = _currentUser.ToUserSlim();
 
-        var response = await ChatClient.GetChats(_currentUser.Id);
-        switch (response.StatusCode)
-        {
-            case var _ when response.IsSuccessStatusCode:
-                _chats = response.Content!;
-                break;
-
-            case HttpStatusCode.TooManyRequests:
-                Snackbar.Add(ErrorMessages.High_Load, Severity.Info);
-                break;
-
-            default:
-                Snackbar.Add(ErrorMessages.Something_Went_Wrong_Refresh, Severity.Warning);
-                break;
-        }
+        _chats = await ChatService.GetChats(_currentUser.Id);
 
         _isLoading = false;
     }
@@ -147,23 +120,11 @@
             return;
         }
 
-        var response = await ChatClient.GetChatMessages(_activeChat.Id, _activeChat.Messages.Count, int.MaxValue);
-        switch (response.StatusCode)
-        {
-            case var _ when response.IsSuccessStatusCode:
-                _activeChat.Messages.AddRange(response.Content!);
-                StateHasChanged();
-                await ScrollToBottom();
-                break;
-
-            case HttpStatusCode.TooManyRequests:
-                Snackbar.Add(ErrorMessages.High_Load, Severity.Info);
-                break;
-
-            default:
-                Snackbar.Add(ErrorMessages.Something_Went_Wrong_Refresh, Severity.Warning);
-                break;
-        }
+        _activeChat.Messages = await ChatService.GetChatMessages(_activeChat.Id);
+
+        StateHasChanged();
+
+        await ScrollToBottom();
     }
 
     private async Task SelectChat(ChatDto chat)
@@ -172,6 +133,8 @@
         if (_isActiveChatPublished)
         {
             await LoadMessages();
+            // We call this twice to ensure we're at the very bottom. Silly but easy
+            await ScrollToBottom();
         }
     }
 
@@ -200,13 +163,12 @@
 
         if (_isActiveChatPublished)
         {
-            // TODO: Error handling
-            await ChatClient.SendMessage(message);
+            await ChatService.SendMessage(message);
         }
         else
         {
-            // TODO: Error handling
-            await ChatClient.StartChat(_activeChat);
+            await ChatService.StartChat(_activeChat);
+            _isActiveChatPublished = true;
         }
 
         await ScrollToBottom();

src/web/Client/Program.cs

@@ -65,6 +65,8 @@
 builder.Services.Configure<DataForsyningenOptions>(
     builder.Configuration.GetSection(DataForsyningenOptions.SectionName));
 
+builder.Services.AddScoped<IChatService, ChatService>();
+
 var host = builder.Build();
 
 await host.RunAsync();

src/web/Client/_Imports.razor

@@ -28,3 +28,7 @@
 @using MudExtensions
 @using Blazored.LocalStorage
 @using Blazored.SessionStorage
+@using System.Globalization
+@using System.Linq.Expressions
+@using System.Security.Claims
+@using MassTransit

src/web/Shared/Chat/ChatDto.cs

@@ -12,7 +12,7 @@ public class ChatDto
     /// </summary>
     public string? DisplayName { get; init; }
 
-    public List<ChatMessageDto> Messages { get; init; } = new();
+    public List<ChatMessageDto> Messages { get; set; } = new();
     public List<UserSlim> Recipients { get; init; } = new();
 
     public DateTime LastMessageSentUtc { get; init; }