source: binary-improvements/MapRendering/Web/Handlers/ApiHandler.cs@ 375

using System;
using System.Collections.Generic;
using System.Net;
using System.Reflection;
using AllocsFixes.NetConnections.Servers.Web.API;

namespace AllocsFixes.NetConnections.Servers.Web.Handlers {
        public class ApiHandler : PathHandler {
                private readonly Dictionary<string, WebAPI> apis = new CaseInsensitiveStringDictionary<WebAPI> ();

                public ApiHandler (string _moduleName = null) : base (_moduleName) {

                        foreach (Type t in Assembly.GetExecutingAssembly ().GetTypes ()) {
                                if (!t.IsAbstract && t.IsSubclassOf (typeof (WebAPI))) {
                                        ConstructorInfo ctor = t.GetConstructor (new Type [0]);
                                        if (ctor != null) {
                                                WebAPI apiInstance = (WebAPI) ctor.Invoke (new object [0]);
                                                addApi (apiInstance);
                                        }
                                }
                        }

                        // Permissions that don't map to a real API
                        addApi (new Null ("viewallclaims"));
                        addApi (new Null ("viewallplayers"));
                }

                private void addApi (WebAPI _api) {
                        apis.Add (_api.Name, _api);
                        WebPermissions.Instance.AddKnownModule ("webapi." + _api.Name, _api.DefaultPermissionLevel ());
                }

#if ENABLE_PROFILER
                private static readonly UnityEngine.Profiling.CustomSampler apiHandlerSampler = UnityEngine.Profiling.CustomSampler.Create ("API_Handler");
#endif

                public override void HandleRequest (HttpListenerRequest _req, HttpListenerResponse _resp, WebConnection _user,
                        int _permissionLevel) {
                        string apiName = _req.Url.AbsolutePath.Remove (0, urlBasePath.Length);

                        if (!apis.TryGetValue (apiName, out WebAPI api)) {
                                Log.Out ($"Error in {nameof(ApiHandler)}.HandleRequest(): No handler found for API \"{apiName}\"");
                                _resp.StatusCode = (int) HttpStatusCode.NotFound;
                                return;
                        }

                        if (!AuthorizeForApi (apiName, _permissionLevel)) {
                                _resp.StatusCode = (int) HttpStatusCode.Forbidden;
                                if (_user != null) {
                                        //Log.Out ($"{nameof(ApiHandler)}: user '{user.SteamID}' not allowed to execute '{apiName}'");
                                }

                                return;
                        }

                        try {
#if ENABLE_PROFILER
                                apiHandlerSampler.Begin ();
#endif
                                api.HandleRequest (_req, _resp, _user, _permissionLevel);
#if ENABLE_PROFILER
                                apiHandlerSampler.End ();
#endif
                        } catch (Exception e) {
                                Log.Error ($"Error in {nameof(ApiHandler)}.HandleRequest(): Handler {api.Name} threw an exception:");
                                Log.Exception (e);
                                _resp.StatusCode = (int) HttpStatusCode.InternalServerError;
                        }
                }

                private bool AuthorizeForApi (string _apiName, int _permissionLevel) {
                        return WebPermissions.Instance.ModuleAllowedWithLevel ("webapi." + _apiName, _permissionLevel);
                }
        }
}