Fixes #358 MockGeneratorPlugin errors if the response headers have a duplicate

dev-proxy-abstractions/GraphBatchResponsePayload.cs

@@ -20,7 +20,7 @@ public class GraphBatchResponsePayloadResponse
     [JsonPropertyName("body")]
     public dynamic? Body { get; set; }
     [JsonPropertyName("headers")]
-    public Dictionary<string, string>? Headers { get; set; }
+    public List<KeyValuePair<string, string>>? Headers { get; set; }
 }
 
 public class GraphBatchResponsePayloadResponseBody

dev-proxy-plugins/Behavior/RateLimitingPlugin.cs

@@ -203,8 +203,8 @@ _urlsToWatch is null ||
                 if (_configuration.CustomResponse is not null)
                 {
                     var headers = _configuration.CustomResponse.Headers is not null ?
-                        _configuration.CustomResponse.Headers.Select(h => new HttpHeader(h.Key, h.Value)) :
-                        Array.Empty<HttpHeader>();
+                        _configuration.CustomResponse.Headers.Select(kvp => new HttpHeader(kvp.Key, kvp.Value)).ToArray():
+                    Array.Empty<HttpHeader>();
 
                     // allow custom throttling response
                     var responseCode = (HttpStatusCode)(_configuration.CustomResponse.StatusCode ?? 200);

dev-proxy-plugins/MockResponses/GraphMockResponsePlugin.cs

@@ -60,7 +60,7 @@ protected override async Task OnRequest(object? sender, ProxyRequestArgs e)
                 {
                     Id = request.Id,
                     Status = (int)HttpStatusCode.BadGateway,
-                    Headers = headersDictionary,
+                    Headers = headersDictionary.Select(x => new KeyValuePair<string, string>(x.Key, x.Value)).ToList(),
                     Body = new GraphBatchResponsePayloadResponseBody
                     {
                         Error = new GraphBatchResponsePayloadResponseBodyError
@@ -84,11 +84,13 @@ protected override async Task OnRequest(object? sender, ProxyRequestArgs e)
 
                 if (mockResponse.Response?.Headers is not null)
                 {
-                    foreach (var key in mockResponse.Response.Headers.Keys)
+                    //Add all the mocked headers into the response we want
+                    foreach (var kvp in mockResponse.Response.Headers)
                     {
-                        headersDictionary[key] = mockResponse.Response.Headers[key];
+                        headersDictionary.Add(kvp.Key, kvp.Value);
                     }
                 }
+
                 // default the content type to application/json unless set in the mock response
                 if (!headersDictionary.Any(h => h.Key.Equals("content-type", StringComparison.OrdinalIgnoreCase)))
                 {
@@ -127,7 +129,7 @@ protected override async Task OnRequest(object? sender, ProxyRequestArgs e)
                 {
                     Id = request.Id,
                     Status = (int)statusCode,
-                    Headers = headersDictionary,
+                    Headers = headersDictionary.Select(x => new KeyValuePair<string, string>(x.Key, x.Value)).ToList(),
                     Body = body
                 };
 

dev-proxy-plugins/MockResponses/MockResponse.cs

@@ -30,5 +30,5 @@ public class MockResponseResponse
     [JsonPropertyName("body")]
     public dynamic? Body { get; set; }
     [JsonPropertyName("headers")]
-    public IDictionary<string, string>? Headers { get; set; }
+    public List<KeyValuePair<string, string>>? Headers { get; set; }
 }

dev-proxy-plugins/MockResponses/MockResponsePlugin.cs

@@ -9,7 +9,6 @@
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Text.RegularExpressions;
-using Titanium.Web.Proxy.EventArguments;
 using Titanium.Web.Proxy.Http;
 using Titanium.Web.Proxy.Models;
 using Microsoft.DevProxy.Plugins.Behavior;
@@ -217,18 +216,12 @@ private void ProcessMockResponse(ProxyRequestArgs e, MockResponse matchingRespon
 
         if (matchingResponse.Response?.Headers is not null)
         {
-            foreach (var key in matchingResponse.Response.Headers.Keys)
+            foreach (HttpHeader headerToAdd in matchingResponse.Response.Headers.Select(kvp => new HttpHeader(kvp.Key, kvp.Value)))
             {
-                // remove duplicate headers
-                var existingHeader = headers.FirstOrDefault(h => h.Name.Equals(key, StringComparison.OrdinalIgnoreCase));
-                if (existingHeader is not null)
-                {
-                    headers.Remove(existingHeader);
-                }
-
-                headers.Add(new HttpHeader(key, matchingResponse.Response.Headers[key]));
+                headers.Add(headerToAdd);
             }
         }
+
         // default the content type to application/json unless set in the mock response
         if (!headers.Any(h => h.Name.Equals("content-type", StringComparison.OrdinalIgnoreCase)))
         {

dev-proxy-plugins/RandomErrors/GraphRandomErrorPlugin.cs

@@ -147,9 +147,7 @@ private void FailBatch(ProxyRequestArgs e)
                     var retryAfterDate = DateTime.Now.AddSeconds(retryAfterInSeconds);
                     var requestUrl = ProxyUtils.GetAbsoluteRequestUrlFromBatch(e.Session.HttpClient.Request.RequestUri, request.Url);
                     e.ThrottledRequests.Add(new ThrottlerInfo(GraphUtils.BuildThrottleKey(requestUrl), ShouldThrottle, retryAfterDate));
-                    response.Headers = new Dictionary<string, string>{
-                        { "Retry-After", retryAfterInSeconds.ToString() }
-                    };
+                    response.Headers = new List<KeyValuePair<string, string>>{new ( "Retry-After", retryAfterInSeconds.ToString())};
                 }
 
                 responses.Add(response);

dev-proxy-plugins/RequestLogs/MockGeneratorPlugin.cs

@@ -51,6 +51,8 @@ request.Context is null ||
             var methodAndUrl = GetMethodAndUrl(methodAndUrlString);
             var response = request.Context.Session.HttpClient.Response;
 
+            var newHeaders = new List<KeyValuePair<string, string>>();
+            newHeaders.AddRange(response.Headers.Select(h => new KeyValuePair<string, string>(h.Name, h.Value)));
             var mock = new MockResponse
             {
                 Request = new()
@@ -61,9 +63,7 @@ request.Context is null ||
                 Response = new()
                 {
                     StatusCode = response.StatusCode,
-                    Headers = response.Headers
-                        .Select(h => new KeyValuePair<string, string>(h.Name, h.Value))
-                        .ToDictionary(kvp => kvp.Key, kvp => kvp.Value),
+                    Headers = newHeaders,
                     Body = GetResponseBody(request.Context.Session).Result
                 }
             };