Foxnouns.NET/Foxnouns.Backend/Controllers/InternalController.cs

123 lines
4.8 KiB
C#

// Copyright (C) 2023-present sam/u1f320 (vulpine.solutions)
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
using System.Text.RegularExpressions;
using Foxnouns.Backend.Database;
using Foxnouns.Backend.Dto;
using Foxnouns.Backend.Utils;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Controllers;
using Microsoft.AspNetCore.Mvc.Routing;
using Microsoft.AspNetCore.Routing.Template;
namespace Foxnouns.Backend.Controllers;
[ApiController]
[Route("/api/internal")]
[ApiExplorerSettings(IgnoreApi = true)]
public partial class InternalController(DatabaseContext db) : ControllerBase
{
[GeneratedRegex(@"(\{\w+\})")]
private static partial Regex PathVarRegex();
[GeneratedRegex(@"\{id\}")]
private static partial Regex IdCountRegex();
private static string GetCleanedTemplate(string template)
{
if (template.StartsWith("api/v2"))
template = template["api/v2".Length..];
else if (template.StartsWith("api/v1"))
template = template["api/v1".Length..];
template = PathVarRegex()
.Replace(template, "{id}") // Replace all path variables (almost always IDs) with `{id}`
.Replace("@me", "{id}"); // Also replace hardcoded `@me` with `{id}`
// If there's at least one path parameter, we only return the *first* part of the path.
if (template.Contains("{id}"))
{
// However, if the path starts with /users/{id} *and* there's another path parameter (such as a member ID)
// we ignore the leading /users/{id}. This is because a lot of routes are scoped by user, but should have
// separate rate limits from other user-scoped routes.
if (template.StartsWith("/users/{id}/") && IdCountRegex().Count(template) >= 2)
template = template["/users/{id}".Length..];
return template.Split("{id}")[0] + "{id}";
}
return template;
}
[HttpPost("request-data")]
public async Task<IActionResult> GetRequestDataAsync([FromBody] RequestDataRequest req)
{
RouteEndpoint? endpoint = GetEndpoint(HttpContext, req.Path, req.Method);
if (endpoint == null)
throw new ApiError.BadRequest("Path/method combination is invalid");
ControllerActionDescriptor? actionDescriptor =
endpoint.Metadata.GetMetadata<ControllerActionDescriptor>();
string? template = actionDescriptor?.AttributeRouteInfo?.Template;
if (template == null)
throw new FoxnounsError("Template value was null on valid endpoint");
template = GetCleanedTemplate(template);
// If no token was supplied, or it isn't valid base 64, return a null user ID (limiting by IP)
if (!AuthUtils.TryParseToken(req.Token, out byte[]? rawToken))
return Ok(new RequestDataResponse(null, template));
Snowflake? userId = await db.GetTokenUserId(rawToken);
return Ok(new RequestDataResponse(userId, template));
}
private static RouteEndpoint? GetEndpoint(
HttpContext httpContext,
string url,
string requestMethod
)
{
EndpointDataSource? endpointDataSource =
httpContext.RequestServices.GetService<EndpointDataSource>();
if (endpointDataSource == null)
return null;
IEnumerable<RouteEndpoint> endpoints = endpointDataSource.Endpoints.OfType<RouteEndpoint>();
foreach (RouteEndpoint? endpoint in endpoints)
{
if (endpoint.RoutePattern.RawText == null)
continue;
var templateMatcher = new TemplateMatcher(
TemplateParser.Parse(endpoint.RoutePattern.RawText),
new RouteValueDictionary()
);
if (!templateMatcher.TryMatch(url, new RouteValueDictionary()))
continue;
HttpMethodAttribute? httpMethodAttribute =
endpoint.Metadata.GetMetadata<HttpMethodAttribute>();
if (
httpMethodAttribute?.HttpMethods.Any(x =>
x.Equals(requestMethod, StringComparison.OrdinalIgnoreCase)
) == false
)
{
continue;
}
return endpoint;
}
return null;
}
}