fix: avoid creating new http clients to load additional documents of the workspace

Signed-off-by: Vincent Biret <[email protected]>

Author: baywet

src/Microsoft.OpenApi/Reader/OpenApiModelFactory.cs

@@ -263,7 +263,7 @@ private static async Task<OpenApiDiagnostic> LoadExternalRefsAsync(OpenApiDocume
             var openApiWorkSpace = new OpenApiWorkspace(baseUrl);
 
             // Load this root document into the workspace
-            var streamLoader = new DefaultStreamLoader(settings.BaseUrl);
+            var streamLoader = new DefaultStreamLoader(settings.BaseUrl, settings.HttpClient);
             var workspaceLoader = new OpenApiWorkspaceLoader(openApiWorkSpace, settings.CustomExternalLoader ?? streamLoader, settings);
             return await workspaceLoader.LoadAsync(new OpenApiReference() { ExternalResource = "/" }, document, format ?? OpenApiConstants.Json, null, token).ConfigureAwait(false);
         }

src/Microsoft.OpenApi/Reader/Services/DefaultStreamLoader.cs

@@ -18,15 +18,17 @@ namespace Microsoft.OpenApi.Reader.Services
     public class DefaultStreamLoader : IStreamLoader
     {
         private readonly Uri baseUrl;
-        private readonly HttpClient _httpClient = new();
+        private readonly HttpClient _httpClient;
 
         /// <summary>
         /// The default stream loader
         /// </summary>
         /// <param name="baseUrl"></param>
-        public DefaultStreamLoader(Uri baseUrl)
+        /// <param name="httpClient">The HttpClient to use to retrieve documents when needed</param>
+        public DefaultStreamLoader(Uri baseUrl, HttpClient httpClient)
         {
             this.baseUrl = baseUrl;
+            _httpClient = Utils.CheckArgumentNull(httpClient);
         }
 
         /// <inheritdoc/>