Initial commit

.editorconfig

@@ -0,0 +1,132 @@
+###############################
+# Core EditorConfig Options   #
+###############################
+root = true
+# All files
+[*]
+indent_style = space
+
+# XML project files
+[*.{csproj,vbproj,vcxproj,vcxproj.filters,proj,projitems,shproj}]
+indent_size = 2
+
+# XML config files
+[*.{props,targets,ruleset,config,nuspec,resx,vsixmanifest,vsct}]
+indent_size = 2
+
+# Code files
+[*.{cs,csx,vb,vbx}]
+indent_size = 4
+insert_final_newline = true
+charset = utf-8-bom
+###############################
+# .NET Coding Conventions     #
+###############################
+[*.{cs,vb}]
+# Organize usings
+dotnet_sort_system_directives_first = true
+# this. preferences
+dotnet_style_qualification_for_field = false:silent
+dotnet_style_qualification_for_property = false:silent
+dotnet_style_qualification_for_method = false:silent
+dotnet_style_qualification_for_event = false:silent
+# Language keywords vs BCL types preferences
+dotnet_style_predefined_type_for_locals_parameters_members = true:silent
+dotnet_style_predefined_type_for_member_access = true:silent
+# Parentheses preferences
+dotnet_style_parentheses_in_arithmetic_binary_operators = always_for_clarity:silent
+dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity:silent
+dotnet_style_parentheses_in_other_binary_operators = always_for_clarity:silent
+dotnet_style_parentheses_in_other_operators = never_if_unnecessary:silent
+# Modifier preferences
+dotnet_style_require_accessibility_modifiers = for_non_interface_members:silent
+dotnet_style_readonly_field = true:suggestion
+# Expression-level preferences
+dotnet_style_object_initializer = true:suggestion
+dotnet_style_collection_initializer = true:suggestion
+dotnet_style_explicit_tuple_names = true:suggestion
+dotnet_style_null_propagation = true:suggestion
+dotnet_style_coalesce_expression = true:suggestion
+dotnet_style_prefer_is_null_check_over_reference_equality_method = true:silent
+dotnet_style_prefer_inferred_tuple_names = true:suggestion
+dotnet_style_prefer_inferred_anonymous_type_member_names = true:suggestion
+dotnet_style_prefer_auto_properties = true:silent
+dotnet_style_prefer_conditional_expression_over_assignment = true:silent
+dotnet_style_prefer_conditional_expression_over_return = true:silent
+###############################
+# Naming Conventions          #
+###############################
+# Style Definitions
+dotnet_naming_style.pascal_case_style.capitalization = pascal_case
+# Use PascalCase for constant fields  
+dotnet_naming_rule.constant_fields_should_be_pascal_case.severity = suggestion
+dotnet_naming_rule.constant_fields_should_be_pascal_case.symbols = constant_fields
+dotnet_naming_rule.constant_fields_should_be_pascal_case.style = pascal_case_style
+dotnet_naming_symbols.constant_fields.applicable_kinds = field
+dotnet_naming_symbols.constant_fields.applicable_accessibilities = *
+dotnet_naming_symbols.constant_fields.required_modifiers = const
+###############################
+# C# Coding Conventions       #
+###############################
+[*.cs]
+# var preferences
+csharp_style_var_for_built_in_types = true:silent
+csharp_style_var_when_type_is_apparent = true:silent
+csharp_style_var_elsewhere = true:silent
+# Expression-bodied members
+csharp_style_expression_bodied_methods = false:silent
+csharp_style_expression_bodied_constructors = false:silent
+csharp_style_expression_bodied_operators = false:silent
+csharp_style_expression_bodied_properties = true:silent
+csharp_style_expression_bodied_indexers = true:silent
+csharp_style_expression_bodied_accessors = true:silent
+# Pattern matching preferences
+csharp_style_pattern_matching_over_is_with_cast_check = true:suggestion
+csharp_style_pattern_matching_over_as_with_null_check = true:suggestion
+# Null-checking preferences
+csharp_style_throw_expression = true:suggestion
+csharp_style_conditional_delegate_call = true:suggestion
+# Modifier preferences
+csharp_preferred_modifier_order = public, private, protected, internal, static, extern, new, virtual, abstract, sealed, override, readonly, unsafe, volatile, async:suggestion
+# Expression-level preferences
+csharp_prefer_braces = true:silent
+csharp_style_deconstructed_variable_declaration = true:suggestion
+csharp_prefer_simple_default_expression = true:suggestion
+csharp_style_pattern_local_over_anonymous_function = true:suggestion
+csharp_style_inlined_variable_declaration = true:suggestion
+###############################
+# C# Formatting Rules         #
+###############################
+# New line preferences
+csharp_new_line_before_open_brace = all
+csharp_new_line_before_else = true
+csharp_new_line_before_catch = true
+csharp_new_line_before_finally = true
+csharp_new_line_before_members_in_object_initializers = true
+csharp_new_line_before_members_in_anonymous_types = true
+csharp_new_line_between_query_expression_clauses = true
+# Indentation preferences
+csharp_indent_case_contents = true
+csharp_indent_switch_labels = true
+csharp_indent_labels = flush_left
+# Space preferences
+csharp_space_after_cast = false
+csharp_space_after_keywords_in_control_flow_statements = true
+csharp_space_between_method_call_parameter_list_parentheses = false
+csharp_space_between_method_declaration_parameter_list_parentheses = false
+csharp_space_between_parentheses = false
+csharp_space_before_colon_in_inheritance_clause = true
+csharp_space_after_colon_in_inheritance_clause = true
+csharp_space_around_binary_operators = before_and_after
+csharp_space_between_method_declaration_empty_parameter_list_parentheses = false
+csharp_space_between_method_call_name_and_opening_parenthesis = false
+csharp_space_between_method_call_empty_parameter_list_parentheses = false
+# Wrapping preferences
+csharp_preserve_single_line_statements = true
+csharp_preserve_single_line_blocks = true
+###############################
+# VB Coding Conventions       #
+###############################
+[*.vb]
+# Modifier preferences
+visual_basic_preferred_modifier_order = Partial, Default, Private, Protected, Public, Friend, NotOverridable, Overridable, MustOverride, Overloads, Overrides, MustInherit, NotInheritable, Static, Shared, Shadows, ReadOnly, WriteOnly, Dim, Const, WithEvents, Widening, Narrowing, Custom, Async:suggestion

.gitignore

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+.vscode/
+bin/
+obj/
+.vs/
+*.csproj.user
+launchSettings.json
+.idea/
+config.json
+config-tokens.json
+.DS_Store
+DataDir*
+.build/

Dockerfile

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+# syntax=docker/dockerfile:1
+
+FROM mcr.microsoft.com/dotnet/sdk:6.0.403-alpine3.16 AS builder
+WORKDIR /src
+COPY src /src/
+RUN dotnet publish -c Release /src/FakeRelay.sln -o /app
+
+FROM mcr.microsoft.com/dotnet/aspnet:6.0.11-alpine3.16  
+VOLUME ["/data"]
+ENV CONFIG_PATH=/data/config.json
+COPY --from=builder /app /app
+RUN ln -s /app/FakeRelay.Cli /bin/fakerelay
+RUN ln -s /app/FakeRelay.Web /bin/web
+ENTRYPOINT ["fakerelay"]

src/Directory.Build.props

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="Current" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <PackageReference Include="Nerdbank.GitVersioning" Condition="!Exists('packages.config')">
+      <Version>3.4.255</Version>
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+  </ItemGroup>
+</Project>

src/FakeRelay.Cli/Commands/AddHostCommand.cs

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+using FakeRelay.Core.Helpers;
+using Spectre.Console;
+using Spectre.Console.Cli;
+
+namespace FakeRelay.Cli.Commands;
+
+public class AddHostCommand : AsyncCommand<HostSettings>
+{
+    public override async Task<int> ExecuteAsync(CommandContext context, HostSettings settings)
+    {
+        var token = await ApiKeysHelper.AddTokenForHostAsync(settings.Host);
+        AnsiConsole.Markup($"[green]Key generated for {settings.Host}[/]\n");
+        AnsiConsole.Markup($"[red]{token}[/]\n");
+        return 0;
+    }
+}

src/FakeRelay.Cli/Commands/DeleteHostCommand.cs

@@ -0,0 +1,15 @@
+using FakeRelay.Core.Helpers;
+using Spectre.Console;
+using Spectre.Console.Cli;
+
+namespace FakeRelay.Cli.Commands;
+
+public class DeleteHostCommand: AsyncCommand<HostSettings>
+{
+    public override async Task<int> ExecuteAsync(CommandContext context, HostSettings settings)
+    {
+        await ApiKeysHelper.DeleteTokenForHostAsync(settings.Host);
+        AnsiConsole.Markup($"[green]Key deleted for {settings.Host}[/]\n");
+        return 0;
+    }
+}

src/FakeRelay.Cli/Commands/UpdateHostCommand.cs

@@ -0,0 +1,16 @@
+using FakeRelay.Core.Helpers;
+using Spectre.Console;
+using Spectre.Console.Cli;
+
+namespace FakeRelay.Cli.Commands;
+
+public class UpdateHostCommand : AsyncCommand<HostSettings>
+{
+    public override async Task<int> ExecuteAsync(CommandContext context, HostSettings settings)
+    {
+        var token = await ApiKeysHelper.UpdateTokenForHostAsync(settings.Host);
+        AnsiConsole.Markup($"[green]Key generated for {settings.Host}[/]\n");
+        AnsiConsole.Markup($"[red]{token}[/]\n");
+        return 0;
+    }
+}

src/FakeRelay.Cli/FakeRelay.Cli.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Spectre.Console.Cli" Version="0.45.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\FakeRelay.Core\FakeRelay.Core.csproj" />
+  </ItemGroup>
+
+</Project>

src/FakeRelay.Cli/HostSettings.cs

@@ -0,0 +1,9 @@
+using Spectre.Console.Cli;
+
+namespace FakeRelay.Cli;
+
+public class HostSettings : CommandSettings
+{
+    [CommandArgument(0, "<HOST>")]
+    public string Host { get; set; }
+}

src/FakeRelay.Cli/Program.cs

@@ -0,0 +1,15 @@
+using FakeRelay.Cli.Commands;
+using FakeRelay.Core;
+using Spectre.Console.Cli;
+
+var app = new CommandApp();
+app.Configure(config =>
+{
+    config.AddCommand<AddHostCommand>("add-host");
+    config.AddCommand<UpdateHostCommand>("update-host");
+    config.AddCommand<DeleteHostCommand>("delete-host");
+});
+
+Config.Init(Environment.GetEnvironmentVariable("CONFIG_PATH"));
+
+return app.Run(args);

src/FakeRelay.Core/ActivityPubModel.cs

@@ -0,0 +1,10 @@
+namespace FakeRelay.Core;
+
+public class ActivityPubModel
+{
+    public string Id { get; set; }
+    public string Actor { get; set; }
+    private Uri? _actorUrl;
+    public Uri ActorUrl => _actorUrl ??= new Uri(Actor);
+    public string Type { get; set; }
+}

src/FakeRelay.Core/Config.cs

@@ -0,0 +1,46 @@
+using System.Security.Cryptography;
+using Jil;
+
+namespace FakeRelay.Core;
+
+public class Config
+{
+    public static Config? Instance { get; private set; }
+    
+    public byte[] PrivateKey { get; }
+    public string PublicKey { get; }
+    public string Host { get; }
+    
+    public string ConfigPath { get; }
+
+    private Config(string publicKey, byte[] privateKey, string host, string configPath)
+    {
+        PrivateKey = privateKey;
+        PublicKey = publicKey;
+        Host = host;
+        ConfigPath = configPath;
+    }
+
+    public static void Init(string path)
+    {
+        if (Instance != null)
+        {
+            return;
+        }
+
+        var data = JSON.Deserialize<ConfigData>(File.ReadAllText(path));
+        if (data.PublicKey == null || data.PrivateKey == null || data.Host == null)
+        {
+            throw new Exception("Missing config parameters");
+        }
+        
+        Instance = new Config(data.PublicKey, Convert.FromBase64String(data.PrivateKey), data.Host, path);
+    }
+
+    private class ConfigData
+    {
+        public string? PublicKey { get; private set; }
+        public string? PrivateKey { get; private set; }
+        public string? Host { get; private set; }
+    }
+}

src/FakeRelay.Core/FakeRelay.Core.csproj

@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Jil" Version="2.17.0" />
+  </ItemGroup>
+
+</Project>

src/FakeRelay.Core/Helpers/ApiKeysHelper.cs

@@ -0,0 +1,77 @@
+using System.Collections.Immutable;
+using System.Security.Cryptography;
+using Jil;
+
+namespace FakeRelay.Core.Helpers;
+
+public static class ApiKeysHelper
+{
+    private static string? _tokensFilePath;
+    private static string TokensFilePath => _tokensFilePath ??= Config.Instance.ConfigPath.Replace(".json", "-tokens.json");
+
+    public static async Task<ImmutableDictionary<string, string>> GetTokenToHostAsync()
+    {
+        if (!File.Exists(TokensFilePath))
+        {
+            return ImmutableDictionary<string, string>.Empty;
+        }
+        
+        var content = await File.ReadAllTextAsync(TokensFilePath);
+        return JSON.Deserialize<Dictionary<string, string>>(content)
+            .ToImmutableDictionary(StringComparer.OrdinalIgnoreCase);
+    }
+
+    public static async Task<string> UpdateTokenForHostAsync(string host)
+    {
+        var dict = await GetTokenToHostAsync();
+        var hostToKeys = dict.ToLookup(d => d.Value, d => d.Key, StringComparer.OrdinalIgnoreCase);
+        if (!hostToKeys.Contains(host))
+        {
+            throw new ArgumentException("The host doesn't have a key", nameof(host));
+        }
+
+        foreach (var key in hostToKeys[host])
+        {
+            dict = dict.Remove(key);
+        }
+
+        return await AddTokenForHostAsync(host, dict);
+    }
+
+    public static async Task<string> AddTokenForHostAsync(string host) =>
+        await AddTokenForHostAsync(host, await GetTokenToHostAsync());
+
+    public static async Task DeleteTokenForHostAsync(string host)
+    {
+        var dict = await GetTokenToHostAsync();
+        var hostToKeys = dict.ToLookup(d => d.Value, d => d.Key, StringComparer.OrdinalIgnoreCase);
+        if (!hostToKeys.Contains(host))
+        {
+            throw new ArgumentException("The host does not have a key", nameof(host));
+        }
+
+        foreach (var key in hostToKeys[host])
+        {
+            dict = dict.Remove(key);
+        }
+        
+        var content = JSON.Serialize(dict);
+        await File.WriteAllTextAsync(TokensFilePath, content);
+    }
+
+    private static async Task<string> AddTokenForHostAsync(string host, ImmutableDictionary<string, string> dict)
+    {
+        var hostToKeys = dict.ToLookup(d => d.Value, d => d.Key, StringComparer.OrdinalIgnoreCase);
+        if (hostToKeys.Contains(host))
+        {
+            throw new ArgumentException("The host already has a key", nameof(host));
+        }
+        
+        var key = Convert.ToBase64String(RandomNumberGenerator.GetBytes(64));
+
+        var content = JSON.Serialize(dict.Add(key, host));
+        await File.WriteAllTextAsync(TokensFilePath, content);
+
+        return key;
+    }
+}

src/FakeRelay.Core/Helpers/CryptographyHelper.cs

@@ -0,0 +1,24 @@
+using System.Security.Cryptography;
+using System.Text;
+
+namespace FakeRelay.Core.Helpers;
+
+public class CryptographyHelper
+{
+    public static string GetSHA256Digest(string content)
+    {
+        using var sha256 = SHA256.Create();
+        var hashValue = sha256.ComputeHash(Encoding.UTF8.GetBytes(content));
+        return Convert.ToBase64String(hashValue);
+    }
+
+    public static string Sign(string stringToSign)
+    {
+        using var rsaProvider = new RSACryptoServiceProvider();
+        using var sha256 = SHA256.Create();
+        rsaProvider.ImportRSAPrivateKey(Config.Instance.PrivateKey, out _);
+    
+        var signature = rsaProvider.SignData(Encoding.UTF8.GetBytes(stringToSign), sha256);
+        return Convert.ToBase64String(signature);
+    }
+}

src/FakeRelay.Core/Helpers/MastodonHelper.cs

@@ -0,0 +1,52 @@
+using System.Net.Http.Headers;
+
+namespace FakeRelay.Core.Helpers;
+
+public static class MastodonHelper
+{
+    public static Task<string> EnqueueStatusToFetchAsync(string targetHost, string statusUrl) =>
+        SendMessageToInboxAsync(targetHost, $@"{{
+    ""@context"": ""https://www.w3.org/ns/activitystreams"",
+    ""actor"": ""https://{Config.Instance.Host}/actor"",
+    ""id"": ""https://{Config.Instance.Host}/activities/{Guid.NewGuid()}"",
+    ""object"": ""{statusUrl}"",
+    ""to"": [
+        ""https://{Config.Instance.Host}/followers""
+    ],
+    ""type"": ""Announce""
+}}");
+
+    public static async Task<string> SendMessageToInboxAsync(string targetHost, string content)
+    {
+        var client = new HttpClient();
+
+        var date = DateTime.UtcNow;
+        
+        var digest = CryptographyHelper.GetSHA256Digest(content);
+        var requestContent = new StringContent(content);
+
+        requestContent.Headers.Add("Digest", "SHA-256=" + digest);
+
+        var stringToSign = $"(request-target): post /inbox\ndate: {date.ToString("R")}\nhost: {targetHost}\ndigest: SHA-256={digest}\ncontent-length: {content.Length}";
+        var signature = CryptographyHelper.Sign(stringToSign);
+        requestContent.Headers.Add("Signature", $@"keyId=""https://{Config.Instance.Host}/actor#main-key"",algorithm=""rsa-sha256"",headers=""(request-target) date host digest content-length"",signature=""{signature}""");
+
+        requestContent.Headers.ContentType = new MediaTypeHeaderValue("application/activity+json");
+        client.DefaultRequestHeaders.Date = date;
+
+        var response = await client.PostAsync($"https://{targetHost}/inbox", requestContent);
+        return await response.Content.ReadAsStringAsync();
+    }
+
+    public static async Task ProcessInstanceFollowAsync(ActivityPubModel request)
+    {
+        var host = request.ActorUrl.Host;
+        await SendMessageToInboxAsync(host, $@"{{""@context"": ""https://www.w3.org/ns/activitystreams"", ""type"": ""Accept"", ""to"": [""https://{host}/actor""], ""actor"": ""https://{Config.Instance.Host}/actor"", ""object"": {{""type"": ""Follow"", ""id"": ""{request.Id}"", ""object"": ""https://{Config.Instance.Host}/actor"", ""actor"": ""{request.Actor}""}}, ""id"": ""https://{Config.Instance.Host}/activities/{Guid.NewGuid()}""}}");
+    }
+
+    public static string GetActorStaticContent() =>
+        $@"{{""@context"": ""https://www.w3.org/ns/activitystreams"", ""endpoints"": {{""sharedInbox"": ""https://{Config.Instance.Host}/inbox""}}, ""followers"": ""https://{Config.Instance.Host}/followers"", ""following"": ""https://{Config.Instance.Host}/following"", ""inbox"": ""https://{Config.Instance.Host}/inbox"", ""name"": ""FakeRelay"", ""type"": ""Application"", ""id"": ""https://{Config.Instance.Host}/actor"", ""publicKey"": {{""id"": ""https://{Config.Instance.Host}/actor#main-key"", ""owner"": ""https://{Config.Instance.Host}/actor"", ""publicKeyPem"": ""{Config.Instance.PublicKey.Replace("\n", "\\n")}""}}, ""summary"": ""FakeRelay bot"", ""preferredUsername"": ""relay"", ""url"": ""https://{Config.Instance.Host}/actor""}}";
+
+    public static string GetActorWebFinger() =>
+        $@"{{""subject"": ""acct:relay@{Config.Instance.Host}"", ""aliases"": [""https://{Config.Instance.Host}/actor""], ""links"": [{{""href"": ""https://{Config.Instance.Host}/actor"", ""rel"": ""self"", ""type"": ""application/activity+json""}}, {{""href"": ""https://{Config.Instance.Host}/actor"", ""rel"": ""self"", ""type"": ""application/ld+json; profile=\""https://www.w3.org/ns/activitystreams\""""}}]}}";
+}

src/FakeRelay.Web/Controllers/AcitivityPubController.cs

@@ -0,0 +1,41 @@
+using FakeRelay.Core;
+using FakeRelay.Core.Helpers;
+using FakeRelay.Web.Services;
+using Microsoft.AspNetCore.Mvc;
+
+namespace FakeRelay.Web.Controllers;
+
+public class AcitivityPubController : Controller
+{
+   
+    [Route("actor")]
+    public async Task<ActionResult> Actor([FromServices] IBackgroundTaskQueue taskQueue) =>
+        Content(MastodonHelper.GetActorStaticContent(), "application/activity+json; charset=utf-8");
+    
+    [Route("inbox"), HttpPost]
+    public async Task<ActionResult> Inbox([FromBody] ActivityPubModel model, [FromServices] IBackgroundTaskQueue taskQueue)
+    {
+        if (model.Type == "Follow")
+        {
+            await taskQueue.QueueBackgroundWorkItemAsync(_ => MastodonHelper.ProcessInstanceFollowAsync(model));
+        }
+
+        return Content("{}", "application/activity+json");
+    }
+
+    [Route(".well-known/webfinger")]
+    public ActionResult WebFinger(string resource)
+    {
+        if (resource == "acct:relay@" + Config.Instance.Host)
+        {
+            return Content(MastodonHelper.GetActorWebFinger(), "application/json; charset=utf-8");
+        }
+
+        return new ContentResult
+        {
+            Content = @"{""error"": ""user not found""}",
+            ContentType = "application/json; charset=utf-8",
+            StatusCode = 404
+        };
+    }
+}

src/FakeRelay.Web/Controllers/ApiController.cs

@@ -0,0 +1,51 @@
+using System.Collections.Immutable;
+using FakeRelay.Core.Helpers;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Caching.Memory;
+
+namespace FakeRelay.Web.Controllers;
+
+public class ApiController : Controller
+{
+    private readonly IMemoryCache _memoryCache;
+
+    public ApiController(IMemoryCache memoryCache)
+    {
+        _memoryCache = memoryCache;
+    }
+
+    private async Task<string?> GetHostFromRequest()
+    {
+        if (Request.Headers.Authorization.Count != 1)
+        {
+            return null;
+        }
+        
+        if (!_memoryCache.TryGetValue("tokenToHost", out ImmutableDictionary<string, string> tokenToHost))
+        {
+            tokenToHost = await ApiKeysHelper.GetTokenToHostAsync();
+
+            var cacheEntryOptions = new MemoryCacheEntryOptions()
+                .SetAbsoluteExpiration(TimeSpan.FromMinutes(2));
+
+            _memoryCache.Set("tokenToHost", tokenToHost, cacheEntryOptions);
+        }
+        
+        var token = Request.Headers.Authorization[0].Replace("Bearer ", "");
+        tokenToHost.TryGetValue(token, out var host);
+        return host;
+    }
+
+    [Route("index")]
+    public async Task<ActionResult> DoIndex(string statusUrl)
+    {
+        var host = await GetHostFromRequest();
+        if (host == null)
+        {
+            return Unauthorized();
+        }
+        
+        var response = await MastodonHelper.EnqueueStatusToFetchAsync(host, statusUrl);
+        return Content(response, "application/activity+json");
+    }
+}

src/FakeRelay.Web/FakeRelay.Web.csproj

@@ -0,0 +1,83 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <ItemGroup>
+    <ProjectReference Include="..\FakeRelay.Core\FakeRelay.Core.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <_ContentIncludedByDefault Remove="Views\Home\Index.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\Home\Privacy.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\Shared\Error.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\Shared\_Layout.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\Shared\_ValidationScriptsPartial.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\_ViewImports.cshtml" />
+    <_ContentIncludedByDefault Remove="Views\_ViewStart.cshtml" />
+    <_ContentIncludedByDefault Remove="wwwroot\css\site.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\favicon.ico" />
+    <_ContentIncludedByDefault Remove="wwwroot\js\site.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.rtl.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.rtl.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.rtl.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-grid.rtl.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.rtl.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.rtl.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.rtl.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-reboot.rtl.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.rtl.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.rtl.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.rtl.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap-utilities.rtl.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.rtl.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.rtl.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.rtl.min.css" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\css\bootstrap.rtl.min.css.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.bundle.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.bundle.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.bundle.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.bundle.min.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.esm.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.esm.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.esm.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.esm.min.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\dist\js\bootstrap.min.js.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\bootstrap\LICENSE" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation-unobtrusive\jquery.validate.unobtrusive.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation-unobtrusive\jquery.validate.unobtrusive.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation-unobtrusive\LICENSE.txt" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation\dist\additional-methods.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation\dist\additional-methods.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation\dist\jquery.validate.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation\dist\jquery.validate.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery-validation\LICENSE.md" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery\dist\jquery.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery\dist\jquery.min.js" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery\dist\jquery.min.map" />
+    <_ContentIncludedByDefault Remove="wwwroot\lib\jquery\LICENSE.txt" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+</Project>

src/FakeRelay.Web/Program.cs

@@ -0,0 +1,46 @@
+using FakeRelay.Core;
+using FakeRelay.Web.Services;
+using Microsoft.AspNetCore.HttpOverrides;
+
+var builder = WebApplication.CreateBuilder(args);
+Config.Init(builder.Configuration.GetValue<string>("CONFIG_PATH"));
+
+// Add services to the container.
+builder.Services.AddControllersWithViews();
+
+builder.Services.Configure<ForwardedHeadersOptions>(options =>
+{
+    options.ForwardedHeaders =
+        ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto;
+
+    // I don't want to know what the nginx ip is. Also: the container that runs this doesn't expose a port to the world
+    options.KnownNetworks.Clear();
+    options.KnownProxies.Clear();
+    
+    options.ForwardLimit = 1;
+});
+
+builder.Services.AddHostedService<QueuedHostedService>();
+builder.Services.AddSingleton<IBackgroundTaskQueue>(_ => new BackgroundTaskQueue(30));
+
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (!app.Environment.IsDevelopment())
+{
+    app.UseExceptionHandler("/Home/Error");
+    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
+    app.UseHsts();
+}
+
+app.UseHttpsRedirection();
+
+app.UseRouting();
+
+app.UseAuthorization();
+
+app.MapControllerRoute(
+    "default",
+    "{controller=Home}/{action=Index}/{id?}");
+
+app.Run();

src/FakeRelay.Web/Services/QueuedHostedService.cs

@@ -0,0 +1,97 @@
+using System.Threading.Channels;
+
+namespace FakeRelay.Web.Services;
+
+public interface IBackgroundTaskQueue
+{
+    ValueTask QueueBackgroundWorkItemAsync(Func<CancellationToken, Task> workItem);
+
+    ValueTask<Func<CancellationToken, Task>> DequeueAsync(
+        CancellationToken cancellationToken);
+}
+
+public class BackgroundTaskQueue : IBackgroundTaskQueue
+{
+    private readonly Channel<Func<CancellationToken, Task>> _queue;
+
+    public BackgroundTaskQueue(int capacity)
+    {
+        // Capacity should be set based on the expected application load and
+        // number of concurrent threads accessing the queue.            
+        // BoundedChannelFullMode.Wait will cause calls to WriteAsync() to return a task,
+        // which completes only when space became available. This leads to backpressure,
+        // in case too many publishers/calls start accumulating.
+        var options = new BoundedChannelOptions(capacity)
+        {
+            FullMode = BoundedChannelFullMode.Wait
+        };
+        _queue = Channel.CreateBounded<Func<CancellationToken, Task>>(options);
+    }
+
+    public async ValueTask QueueBackgroundWorkItemAsync(
+        Func<CancellationToken, Task> workItem)
+    {
+        if (workItem == null)
+        {
+            throw new ArgumentNullException(nameof(workItem));
+        }
+
+        await _queue.Writer.WriteAsync(workItem);
+    }
+
+    public async ValueTask<Func<CancellationToken, Task>> DequeueAsync(
+        CancellationToken cancellationToken)
+    {
+        var workItem = await _queue.Reader.ReadAsync(cancellationToken);
+
+        return workItem;
+    }
+}
+
+public class QueuedHostedService : BackgroundService
+{
+    private readonly ILogger<QueuedHostedService> _logger;
+
+    public QueuedHostedService(IBackgroundTaskQueue taskQueue, 
+        ILogger<QueuedHostedService> logger)
+    {
+        TaskQueue = taskQueue;
+        _logger = logger;
+    }
+
+    public IBackgroundTaskQueue TaskQueue { get; }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        _logger.LogInformation(
+            $"Queued Hosted Service is running.");
+
+        await BackgroundProcessing(stoppingToken);
+    }
+
+    private async Task BackgroundProcessing(CancellationToken stoppingToken)
+    {
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            var workItem = 
+                await TaskQueue.DequeueAsync(stoppingToken);
+
+            try
+            {
+                await workItem(stoppingToken);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, 
+                    "Error occurred executing {WorkItem}.", nameof(workItem));
+            }
+        }
+    }
+
+    public override async Task StopAsync(CancellationToken stoppingToken)
+    {
+        _logger.LogInformation("Queued Hosted Service is stopping.");
+
+        await base.StopAsync(stoppingToken);
+    }
+}

src/FakeRelay.Web/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}

src/FakeRelay.Web/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

src/FakeRelay.sln

@@ -0,0 +1,34 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FakeRelay.Web", "FakeRelay.Web\FakeRelay.Web.csproj", "{9AAB6AC5-AB58-45CF-99D0-B657E694368E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FakeRelay.Core", "FakeRelay.Core\FakeRelay.Core.csproj", "{EA9021D7-9E0A-4988-AC42-52204D135DCA}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FakeRelay.Cli", "FakeRelay.Cli\FakeRelay.Cli.csproj", "{0615568F-5DBD-40E1-9925-98C84DB1EEF3}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{9AAB6AC5-AB58-45CF-99D0-B657E694368E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9AAB6AC5-AB58-45CF-99D0-B657E694368E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9AAB6AC5-AB58-45CF-99D0-B657E694368E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9AAB6AC5-AB58-45CF-99D0-B657E694368E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{EA9021D7-9E0A-4988-AC42-52204D135DCA}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{EA9021D7-9E0A-4988-AC42-52204D135DCA}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{EA9021D7-9E0A-4988-AC42-52204D135DCA}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{EA9021D7-9E0A-4988-AC42-52204D135DCA}.Release|Any CPU.Build.0 = Release|Any CPU
+		{0615568F-5DBD-40E1-9925-98C84DB1EEF3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{0615568F-5DBD-40E1-9925-98C84DB1EEF3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{0615568F-5DBD-40E1-9925-98C84DB1EEF3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{0615568F-5DBD-40E1-9925-98C84DB1EEF3}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal

src/version.json

@@ -0,0 +1,13 @@
+{
+    "$schema": "https://raw.githubusercontent.com/dotnet/Nerdbank.GitVersioning/master/src/NerdBank.GitVersioning/version.schema.json",
+    "version": "1.1",
+    "publicReleaseRefSpec": [
+      "^refs/heads/main$",
+      "^refs/heads/v\\d+(?:\\.\\d+)?$"
+    ],
+    "cloudBuild": {
+      "buildNumber": {
+        "enabled": true
+      }
+    }
+  }