chat: add initial GuildsController

.editorconfig

@@ -2,3 +2,6 @@
 
 # CS9113: Parameter is unread.
 dotnet_diagnostic.CS9113.severity = silent
+
+# EntityFramework.ModelValidation.UnlimitedStringLength
+resharper_entity_framework_model_validation_unlimited_string_length_highlighting=none

.gitignore

@@ -1,3 +1,47 @@
 bin/
 obj/
 .version
+
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+.idea/**/discord.xml
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# CMake
+cmake-build-*/
+
+# File-based project format
+*.iws
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Visual Studio Code
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+!.vscode/*.code-snippets

Foxchat.Chat/Controllers/Api/GuildsController.cs

@@ -0,0 +1,47 @@
+using Foxchat.Chat.Database;
+using Foxchat.Chat.Database.Models;
+using Foxchat.Chat.Middleware;
+using Foxchat.Chat.Services;
+using Foxchat.Core.Models;
+using Foxchat.Core.Models.Http;
+using Microsoft.AspNetCore.Mvc;
+using ApiError = Foxchat.Core.ApiError;
+
+namespace Foxchat.Chat.Controllers.Api;
+
+[ApiController]
+[Route("/_fox/chat/guilds")]
+public class GuildsController(ILogger logger, ChatContext db, UserResolverService userResolverService) : ControllerBase
+{
+    [HttpPost]
+    public async Task<IActionResult> CreateGuild([FromBody] GuildsApi.CreateGuildRequest req)
+    {
+        var (instance, sig) = HttpContext.GetSignatureOrThrow();
+        if (sig.UserId == null) throw new ApiError.IncomingFederationError("This endpoint requires a user ID.");
+
+        var user = await userResolverService.ResolveUserAsync(instance, sig.UserId);
+
+        var guild = new Guild
+        {
+            Name = req.Name,
+            Owner = user,
+        };
+        db.Add(guild);
+        guild.Users.Add(user);
+        var defaultChannel = new Channel
+        {
+            Guild = guild,
+            Name = "general"
+        };
+        db.Add(defaultChannel);
+
+        await db.SaveChangesAsync();
+
+        return Ok(new Guilds.Guild(
+            guild.Id.ToString(), 
+            guild.Name, 
+            [user.Id.ToString()],
+            [new Channels.PartialChannel(defaultChannel.Id.ToString(), defaultChannel.Name)])
+        );
+    }
+}

Foxchat.Chat/Controllers/HelloController.cs

@@ -10,7 +10,7 @@ using ApiError = Foxchat.Core.ApiError;
 namespace Foxchat.Chat.Controllers;
 
 [ApiController]
-[Unauthenticated]
+[ServerUnauthenticated]
 [Route("/_fox/chat/hello")]
 public class HelloController(
     ILogger logger,
@@ -27,6 +27,8 @@ public class HelloController(
 
         if (!HttpContext.ExtractRequestData(out var signature, out var domain, out var signatureData))
             throw new ApiError.IncomingFederationError("This endpoint requires signed requests.");
+        if (domain != req.Host)
+            throw new ApiError.IncomingFederationError("Host is invalid.");
 
         if (!requestSigningService.VerifySignature(node.PublicKey, signature, signatureData))
             throw new ApiError.IncomingFederationError("Signature is not valid.");

Foxchat.Chat/Database/Models/User.cs

@@ -1,3 +1,6 @@
+using Foxchat.Core.Models;
+using NodaTime;
+
 namespace Foxchat.Chat.Database.Models;
 
 public class User : BaseModel
@@ -8,6 +11,7 @@ public class User : BaseModel
     public string Username { get; init; } = null!;
 
     public string? Avatar { get; set; }
+    public Instant LastFetchedAt { get; set; }
 
     public List<Guild> Guilds { get; } = [];
     public List<Guild> OwnedGuilds { get; } = [];

Foxchat.Chat/Extensions/WebApplicationExtensions.cs

@@ -1,4 +1,6 @@
 using Foxchat.Chat.Middleware;
+using Foxchat.Chat.Services;
+using Foxchat.Core.Middleware;
 
 namespace Foxchat.Chat.Extensions;
 
@@ -7,12 +9,20 @@ public static class WebApplicationExtensions
     public static IServiceCollection AddCustomMiddleware(this IServiceCollection services)
     {
         return services
-            .AddScoped<AuthenticationMiddleware>();
+            .AddScoped<ErrorHandlerMiddleware>()
+            .AddScoped<ServerAuthenticationMiddleware>();
     }
 
     public static IApplicationBuilder UseCustomMiddleware(this IApplicationBuilder app)
     {
         return app
-            .UseMiddleware<AuthenticationMiddleware>();
+            .UseMiddleware<ErrorHandlerMiddleware>()
+            .UseMiddleware<ServerAuthenticationMiddleware>();
+    }
+
+    public static IServiceCollection AddChatServices(this IServiceCollection services)
+    {
+        return services
+            .AddScoped<UserResolverService>();
     }
 }

Foxchat.Chat/Middleware/ServerAuthenticationMiddleware.cs

@@ -7,14 +7,14 @@ using Microsoft.EntityFrameworkCore;
 
 namespace Foxchat.Chat.Middleware;
 
-public class AuthenticationMiddleware(ILogger logger, ChatContext db, RequestSigningService requestSigningService)
+public class ServerAuthenticationMiddleware(ILogger logger, ChatContext db, RequestSigningService requestSigningService)
     : IMiddleware
 {
     public async Task InvokeAsync(HttpContext ctx, RequestDelegate next)
     {
         var endpoint = ctx.GetEndpoint();
         // Endpoints require server authentication by default, unless they have the [Unauthenticated] attribute.
-        var metadata = endpoint?.Metadata.GetMetadata<UnauthenticatedAttribute>();
+        var metadata = endpoint?.Metadata.GetMetadata<ServerUnauthenticatedAttribute>();
         if (metadata != null)
         {
             await next(ctx);
@@ -41,8 +41,11 @@ public class AuthenticationMiddleware(ILogger logger, ChatContext db, RequestSig
     }
 }
 
+/// <summary>
+/// Attribute to be put on controllers or methods to indicate that it does <i>not</i> require a signed request.
+/// </summary>
 [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
-public class UnauthenticatedAttribute : Attribute;
+public class ServerUnauthenticatedAttribute : Attribute;
 
 public static class HttpContextExtensions
 {

Foxchat.Chat/Program.cs

@@ -34,6 +34,7 @@ builder.Services
 
 builder.Services
     .AddCoreServices<ChatContext>()
+    .AddChatServices()
     .AddCustomMiddleware()
     .AddEndpointsApiExplorer()
     .AddSwaggerGen();

Foxchat.Chat/Services/UserResolverService.cs

@@ -0,0 +1,35 @@
+using Foxchat.Chat.Database;
+using Foxchat.Chat.Database.Models;
+using Foxchat.Core.Federation;
+using Foxchat.Core.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace Foxchat.Chat.Services;
+
+public class UserResolverService(ILogger logger, ChatContext db, RequestSigningService requestSigningService)
+{
+    public async Task<User> ResolveUserAsync(IdentityInstance instance, string userId)
+    {
+        var user = await db.Users.FirstOrDefaultAsync(u => u.InstanceId == instance.Id && u.RemoteUserId == userId);
+        if (user != null)
+        {
+            // TODO: update user if it's been long enough
+            return user;
+        }
+
+        var userResponse = await requestSigningService.RequestAsync<Users.User>(HttpMethod.Get, instance.Domain,
+            $"/_fox/ident/users/{userId}");
+
+        user = new User
+        {
+            Instance = instance,
+            Username = userResponse.Username,
+            RemoteUserId = userResponse.Id,
+            Avatar = userResponse.AvatarUrl
+        };
+
+        db.Add(user);
+        await db.SaveChangesAsync();
+        return user;
+    }
+}

Foxchat.Core/Extensions/HttpContextExtensions.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using Foxchat.Core.Federation;
 using Microsoft.AspNetCore.Http;
 
@@ -5,11 +6,12 @@ namespace Foxchat.Core.Extensions;
 
 public static class HttpContextExtensions
 {
-    public static bool ExtractRequestData(this HttpContext ctx, out string signature, out string domain, out SignatureData data)
+    public static bool ExtractRequestData(this HttpContext ctx, [NotNullWhen(true)] out string? signature,
+        [NotNullWhen(true)] out string? domain, [NotNullWhen(true)] out SignatureData? data)
     {
-        signature = string.Empty;
-        domain = string.Empty;
-        data = SignatureData.Empty;
+        signature = null;
+        domain = null;
+        data = null;
 
         if (!ctx.Request.Headers.TryGetValue(RequestSigningService.SIGNATURE_HEADER, out var encodedSignature))
             return false;

Foxchat.Core/Federation/RequestSigningService.cs

@@ -33,18 +33,17 @@ public partial class RequestSigningService(ILogger logger, IClock clock, IDataba
     public bool VerifySignature(
         string publicKey, string encodedSignature, SignatureData data)
     {
-        var rsa = RSA.Create();
-        rsa.ImportFromPem(publicKey);
+        if (data.Host != _config.Domain)
+            throw new ApiError.IncomingFederationError("Request is not for this instance");
 
         var now = _clock.GetCurrentInstant();
-        if ((now + Duration.FromMinutes(1)) < data.Time)
-        {
+        if (now + Duration.FromMinutes(1) < data.Time)
             throw new ApiError.IncomingFederationError("Request was made in the future");
-        }
-        else if ((now - Duration.FromMinutes(1)) > data.Time)
-        {
+        if (now - Duration.FromMinutes(1) > data.Time)
             throw new ApiError.IncomingFederationError("Request was made too long ago");
-        }
+
+        var rsa = RSA.Create();
+        rsa.ImportFromPem(publicKey);
 
         var plaintext = GeneratePlaintext(data);
         var plaintextBytes = Encoding.UTF8.GetBytes(plaintext);
@@ -70,7 +69,9 @@ public partial class RequestSigningService(ILogger logger, IClock clock, IDataba
         return $"{time}:{data.Host}:{data.RequestPath}:{contentLength}:{userId}";
     }
 
-    private static readonly InstantPattern _pattern = InstantPattern.Create("ddd, dd MMM yyyy HH:mm:ss 'GMT'", CultureInfo.GetCultureInfo("en-US"));
+    private static readonly InstantPattern _pattern =
+        InstantPattern.Create("ddd, dd MMM yyyy HH:mm:ss 'GMT'", CultureInfo.GetCultureInfo("en-US"));
+
     private static string FormatTime(Instant time) => _pattern.Format(time);
     public static Instant ParseTime(string header) => _pattern.Parse(header).GetValueOrThrow();
 }

Foxchat.Core/Middleware/ErrorHandlerMiddleware.cs

@@ -1,11 +1,10 @@
 using System.Net;
-using Foxchat.Core;
 using Foxchat.Core.Models.Http;
+using Microsoft.AspNetCore.Http;
 using Newtonsoft.Json;
-using ApiError = Foxchat.Core.ApiError;
 using HttpApiError = Foxchat.Core.Models.Http.ApiError;
 
-namespace Foxchat.Identity.Middleware;
+namespace Foxchat.Core.Middleware;
 
 public class ErrorHandlerMiddleware(ILogger baseLogger) : IMiddleware
 {
@@ -23,7 +22,8 @@ public class ErrorHandlerMiddleware(ILogger baseLogger) : IMiddleware
 
             if (ctx.Response.HasStarted)
             {
-                logger.Error(e, "Error in {ClassName} ({Path}) after response started being sent", typeName, ctx.Request.Path);
+                logger.Error(e, "Error in {ClassName} ({Path}) after response started being sent", typeName,
+                    ctx.Request.Path);
             }
 
             if (e is ApiError ae)

Foxchat.Core/Models/Channels.cs

@@ -0,0 +1,8 @@
+namespace Foxchat.Core.Models;
+
+public static class Channels
+{
+    public record Channel(string Id, string GuildId, string Name, string? Topic);
+
+    public record PartialChannel(string Id, string Name);
+}

Foxchat.Core/Models/Guilds.cs

@@ -0,0 +1,14 @@
+using Newtonsoft.Json;
+
+namespace Foxchat.Core.Models;
+
+public static class Guilds
+{
+    public record Guild(
+        string Id,
+        string Name,
+        IEnumerable<string> OwnerIds,
+        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
+        IEnumerable<Channels.PartialChannel>? Channels
+    );
+}

Foxchat.Core/Models/Http/AppsApi.cs

@@ -1,6 +1,6 @@
 namespace Foxchat.Core.Models.Http;
 
-public static class Apps
+public static class AppsApi
 {
     public record CreateRequest(string Name, string[] Scopes, string[] RedirectUris);
     public record CreateResponse(Ulid Id, string ClientId, string ClientSecret, string Name, string[] Scopes, string[] RedirectUris);

Foxchat.Core/Models/Http/GuildsApi.cs

@@ -0,0 +1,6 @@
+namespace Foxchat.Core.Models.Http;
+
+public static class GuildsApi
+{
+    public record CreateGuildRequest(string Name);
+}

Foxchat.Core/Models/Users.cs

@@ -0,0 +1,8 @@
+namespace Foxchat.Core.Models;
+
+public static class Users
+{
+    public record User(string Id, string Username, string Instance, string? AvatarUrl);
+
+    public record PartialUser(string Id, string Username, string Instance);
+}

Foxchat.Identity/Controllers/Oauth/AppsController.cs

@@ -9,12 +9,12 @@ using Microsoft.AspNetCore.Mvc;
 namespace Foxchat.Identity.Controllers.Oauth;
 
 [ApiController]
-[Authenticate]
+[ClientAuthenticate]
 [Route("/_fox/ident/oauth/apps")]
 public class AppsController(ILogger logger, IdentityContext db) : ControllerBase
 {
     [HttpPost]
-    public async Task<IActionResult> CreateApplication([FromBody] Apps.CreateRequest req)
+    public async Task<IActionResult> CreateApplication([FromBody] AppsApi.CreateRequest req)
     {
         var app = Application.Create(req.Name, req.Scopes, req.RedirectUris);
         db.Add(app);
@@ -22,7 +22,7 @@ public class AppsController(ILogger logger, IdentityContext db) : ControllerBase
 
         logger.Information("Created new application {Name} with ID {Id} and client ID {ClientId}", app.Name, app.Id, app.ClientId);
 
-        return Ok(new Apps.CreateResponse(
+        return Ok(new AppsApi.CreateResponse(
             app.Id, app.ClientId, app.ClientSecret, app.Name, app.Scopes, app.RedirectUris
         ));
     }
@@ -32,7 +32,7 @@ public class AppsController(ILogger logger, IdentityContext db) : ControllerBase
     {
         var app = HttpContext.GetApplicationOrThrow();
 
-        return Ok(new Apps.GetSelfResponse(
+        return Ok(new AppsApi.GetSelfResponse(
             app.Id,
             app.ClientId,
             withSecret ? app.ClientSecret : null,

Foxchat.Identity/Controllers/Oauth/PasswordAuthController.cs

@@ -11,7 +11,7 @@ using Microsoft.EntityFrameworkCore;
 namespace Foxchat.Identity.Controllers.Oauth;
 
 [ApiController]
-[Authenticate]
+[ClientAuthenticate]
 [Route("/_fox/ident/oauth/password")]
 public class PasswordAuthController(ILogger logger, IdentityContext db, IClock clock) : ControllerBase
 {

Foxchat.Identity/Controllers/UsersController.cs

@@ -0,0 +1,21 @@
+using Foxchat.Core;
+using Foxchat.Core.Models;
+using Foxchat.Identity.Database;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+namespace Foxchat.Identity.Controllers;
+
+[ApiController]
+[Route("/_fox/ident/users")]
+public class UsersController(ILogger logger, InstanceConfig config, IdentityContext db) : ControllerBase
+{
+    [HttpGet("{id}")]
+    public async Task<IActionResult> GetUser(Ulid id)
+    {
+        var user = await db.Accounts.FirstOrDefaultAsync(a => a.Id == id);
+        if (user == null) throw new ApiError.NotFound("User not found.");
+
+        return Ok(new Users.User(user.Id.ToString(), user.Username, config.Domain, null));
+    }
+}

Foxchat.Identity/Extensions/WebApplicationExtensions.cs

@@ -1,3 +1,4 @@
+using Foxchat.Core.Middleware;
 using Foxchat.Identity.Middleware;
 
 namespace Foxchat.Identity.Extensions;
@@ -8,15 +9,15 @@ public static class WebApplicationExtensions
     {
         return services
             .AddScoped<ErrorHandlerMiddleware>()
-            .AddScoped<AuthenticationMiddleware>()
-            .AddScoped<AuthorizationMiddleware>();
+            .AddScoped<ClientAuthenticationMiddleware>()
+            .AddScoped<ClientAuthorizationMiddleware>();
     }
 
     public static IApplicationBuilder UseCustomMiddleware(this IApplicationBuilder app)
     {
         return app
             .UseMiddleware<ErrorHandlerMiddleware>()
-            .UseMiddleware<AuthenticationMiddleware>()
-            .UseMiddleware<AuthorizationMiddleware>();
+            .UseMiddleware<ClientAuthenticationMiddleware>()
+            .UseMiddleware<ClientAuthorizationMiddleware>();
     }
 }

Foxchat.Identity/Middleware/ClientAuthenticationMiddleware.cs

@@ -8,7 +8,7 @@ using NodaTime;
 
 namespace Foxchat.Identity.Middleware;
 
-public class AuthenticationMiddleware(
+public class ClientAuthenticationMiddleware(
     IdentityContext db,
     IClock clock
 ) : IMiddleware
@@ -16,7 +16,7 @@ public class AuthenticationMiddleware(
     public async Task InvokeAsync(HttpContext ctx, RequestDelegate next)
     {
         var endpoint = ctx.GetEndpoint();
-        var metadata = endpoint?.Metadata.GetMetadata<AuthenticateAttribute>();
+        var metadata = endpoint?.Metadata.GetMetadata<ClientAuthenticateAttribute>();
 
         if (metadata == null)
         {
@@ -81,4 +81,4 @@ public static class HttpContextExtensions
 }
 
 [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
-public class AuthenticateAttribute : Attribute;
+public class ClientAuthenticateAttribute : Attribute;

Foxchat.Identity/Middleware/ClientAuthorizationMiddleware.cs

@@ -4,7 +4,7 @@ using NodaTime;
 
 namespace Foxchat.Identity.Middleware;
 
-public class AuthorizationMiddleware(
+public class ClientAuthorizationMiddleware(
     IdentityContext db,
     IClock clock
 ) : IMiddleware