Excludes processing OPTIONS responses. Closes #371

m365-developer-proxy/ProxyEngine.cs

@@ -60,7 +60,7 @@
         _logger = logger ?? throw new ArgumentNullException(nameof(logger));
     }
 
     public async Task Run(CancellationToken? cancellationToken) {
         if (!_urlsToWatch.Any()) {
             _logger.LogInfo("No URLs to watch configured. Please add URLs to watch in the m365proxyrc.json config file.");
             return;
@@ -73,7 +73,7 @@
         var _logger2 = (ILogger)_logger.Clone();
         _logger2.LogLevel = LogLevel.Warn;
         // let's not await so that it doesn't block the proxy startup
         MSGraphDbCommandHandler.GenerateMsGraphDb(_logger2, true);
 
         _proxyServer = new ProxyServer();
 
@@ -148,7 +148,7 @@
                 StartRecording();
             }
             if (key == ConsoleKey.S) {
                 StopRecording();
             }
             if (key == ConsoleKey.C) {
                 Console.Clear();
@@ -384,8 +384,9 @@
 
     // Modify response
     async Task OnBeforeResponse(object sender, SessionEventArgs e) {
+        var method = e.HttpClient.Request.Method.ToUpper();
         // read response headers
-        if (IsProxiedHost(e.HttpClient.Request.RequestUri.Host)) {
+        if (method is not "OPTIONS" && IsProxiedHost(e.HttpClient.Request.RequestUri.Host)) {
             // necessary to make the response body available to plugins
             e.HttpClient.Response.KeepBody = true;
             await e.GetResponseBody();
@@ -393,11 +394,12 @@
             await _pluginEvents.RaiseProxyBeforeResponse(new ProxyResponseArgs(e, _throttledRequests, new ResponseState()));
         }
     }
     async Task OnAfterResponse(object sender, SessionEventArgs e) {
+        var method = e.HttpClient.Request.Method.ToUpper();
         // read response headers
-        if (IsProxiedHost(e.HttpClient.Request.RequestUri.Host)) {
+        if (method is not "OPTIONS" && IsProxiedHost(e.HttpClient.Request.RequestUri.Host)) {
             _logger.LogRequest(new[] { $"{e.HttpClient.Request.Method} {e.HttpClient.Request.Url}" }, MessageType.InterceptedResponse, new LoggingContext(e));
             _pluginEvents.RaiseProxyAfterResponse(new ProxyResponseArgs(e, _throttledRequests, new ResponseState()));
         }
     }