Add ISwaggerGeneratorSettingsFactory support

src/NSwag.AspNet.Owin/Middlewares/SwaggerMiddleware.cs

@@ -70,7 +70,8 @@ protected virtual async Task<string> GenerateSwaggerAsync(IOwinContext context)
             {
                 try
                 {
-                    var generator = new WebApiToSwaggerGenerator(_settings.GeneratorSettings, _schemaGenerator);
+                    var settings = await _settings.CreateGeneratorSettingsAsync(context, null);
+                    var generator = new WebApiToSwaggerGenerator(settings, _schemaGenerator);
                     var document = await generator.GenerateForControllersAsync(_controllerTypes);
 
                     document.Host = context.Request.Host.Value ?? "";

src/NSwag.AspNetCore/Middlewares/AspNetCoreToSwaggerMiddleware.cs

@@ -13,7 +13,6 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.ApiExplorer;
 using Microsoft.Extensions.Options;
-using NJsonSchema;
 using NSwag.SwaggerGeneration;
 using NSwag.SwaggerGeneration.AspNetCore;
 
@@ -37,6 +36,7 @@ public class AspNetCoreToSwaggerMiddleware
         /// <summary>Initializes a new instance of the <see cref="WebApiToSwaggerMiddleware"/> class.</summary>
         /// <param name="nextDelegate">The next delegate.</param>
         /// <param name="apiDescriptionGroupCollectionProvider">The <see cref="IApiDescriptionGroupCollectionProvider"/>.</param>
+        /// <param name="mvcJsonOptions">The json options.</param>
         /// <param name="settings">The settings.</param>
         /// <param name="schemaGenerator">The schema generator.</param>
         public AspNetCoreToSwaggerMiddleware(RequestDelegate nextDelegate, IApiDescriptionGroupCollectionProvider apiDescriptionGroupCollectionProvider, IOptions<MvcJsonOptions> mvcJsonOptions, SwaggerSettings<AspNetCoreToSwaggerGeneratorSettings> settings, SwaggerJsonSchemaGenerator schemaGenerator)
@@ -79,17 +79,9 @@ protected virtual async Task<string> GenerateSwaggerAsync(HttpContext context)
 
             try
             {
-                // TODO: Move to NJS (same in other generator)
-                var isSerializerSettingsSpecified =
-                    _settings.GeneratorSettings.DefaultPropertyNameHandling != PropertyNameHandling.Default ||
-                    _settings.GeneratorSettings.DefaultEnumHandling != EnumHandling.Integer ||
-                    _settings.GeneratorSettings.ContractResolver != null |
-                    _settings.GeneratorSettings.SerializerSettings != null;
-
-                if (!isSerializerSettingsSpecified)
-                    _settings.GeneratorSettings.SerializerSettings = _mvcJsonOptions.Value.SerializerSettings;
-
-                var generator = new AspNetCoreToSwaggerGenerator(_settings.GeneratorSettings, _schemaGenerator);
+                var serializerSettings = _mvcJsonOptions.Value.SerializerSettings;
+                var settings = await _settings.CreateGeneratorSettingsAsync(context.RequestServices, serializerSettings);
+                var generator = new AspNetCoreToSwaggerGenerator(settings, _schemaGenerator);
                 var document = await generator.GenerateAsync(apiDescriptionGroups);
 
                 document.Host = context.Request.Host.Value ?? "";

src/NSwag.AspNetCore/Middlewares/WebApiToSwaggerMiddleware.cs

@@ -12,7 +12,6 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.Options;
-using NJsonSchema;
 using NSwag.SwaggerGeneration;
 using NSwag.SwaggerGeneration.WebApi;
 
@@ -80,17 +79,9 @@ protected virtual async Task<string> GenerateSwaggerAsync(HttpContext context)
                 {
                     try
                     {
-                        // TODO: Move to NJS (same in other generator)
-                        var isSerializerSettingsSpecified =
-                            _settings.GeneratorSettings.DefaultPropertyNameHandling != PropertyNameHandling.Default ||
-                            _settings.GeneratorSettings.DefaultEnumHandling != EnumHandling.Integer ||
-                            _settings.GeneratorSettings.ContractResolver != null |
-                            _settings.GeneratorSettings.SerializerSettings != null;
-
-                        if (!isSerializerSettingsSpecified)
-                            _settings.GeneratorSettings.SerializerSettings = _mvcJsonOptions.Value.SerializerSettings;
-
-                        var generator = new WebApiToSwaggerGenerator(_settings.GeneratorSettings, _schemaGenerator);
+                        var serializerSettings = _mvcJsonOptions.Value.SerializerSettings;
+                        var settings = await _settings.CreateGeneratorSettingsAsync(context.RequestServices, serializerSettings);
+                        var generator = new WebApiToSwaggerGenerator(settings, _schemaGenerator);
                         var document = await generator.GenerateForControllersAsync(_controllerTypes);
 
                         document.Host = context.Request.Host.Value ?? "";

src/NSwag.AspNetCore/SwaggerSettings.cs

@@ -7,13 +7,20 @@
 //-----------------------------------------------------------------------
 
 using System;
+using System.Threading.Tasks;
 using NJsonSchema;
 using NSwag.SwaggerGeneration;
 using NSwag.SwaggerGeneration.WebApi;
+using Newtonsoft.Json;
 
 #if AspNetOwin
+using Microsoft.Owin;
+
 namespace NSwag.AspNet.Owin
 #else
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.Extensions.DependencyInjection;
+
 namespace NSwag.AspNetCore
 #endif
 {
@@ -22,7 +29,7 @@ public class SwaggerSettings<T>
         where T : SwaggerGeneratorSettings, new()
     {
         /// <summary>Initializes a new instance of the <see cref="SwaggerSettings{T}"/> class.</summary>
-        public SwaggerSettings ()
+        public SwaggerSettings()
         {
             GeneratorSettings = new T();
 
@@ -35,6 +42,13 @@ public SwaggerSettings ()
         /// <summary>Gets the generator settings.</summary>
         public T GeneratorSettings { get; }
 
+        /// <summary>Gets or sets the settings factory.</summary>
+#if !AspNetOwin
+        public ISwaggerGeneratorSettingsFactory<T, IServiceProvider> SettingsFactory { get; set; }
+#else
+        public ISwaggerGeneratorSettingsFactory<T, IOwinContext> SettingsFactory { get; set; }
+#endif
+
         /// <summary>Gets or sets the OWIN base path (when mapped via app.MapOwinPath()) (must start with '/').</summary>
         public string MiddlewareBasePath { get; set; }
 
@@ -48,5 +62,20 @@ public SwaggerSettings ()
         public TimeSpan ExceptionCacheTime { get; set; } = TimeSpan.FromSeconds(10);
 
         internal virtual string ActualSwaggerRoute => SwaggerRoute.Substring(MiddlewareBasePath?.Length ?? 0);
+
+#if !AspNetOwin
+        public async Task<T> CreateGeneratorSettingsAsync(IServiceProvider context, JsonSerializerSettings serializerSettings)
+#else
+        public async Task<T> CreateGeneratorSettingsAsync(IOwinContext context, JsonSerializerSettings serializerSettings)
+#endif
+        {
+            if (SettingsFactory != null)
+                return await SettingsFactory.CreateAsync(serializerSettings, context);
+            else
+            {
+                GeneratorSettings.TryApplySerializerSettings(serializerSettings);
+                return GeneratorSettings;
+            }
+        }
     }
 }

src/NSwag.AssemblyLoader/AssemblyLoader.cs

@@ -36,7 +36,7 @@ public AssemblyLoader()
 
 #endif
 
-        public object CreateInstance(string typeName)
+        public Type GetType(string typeName)
         {
             try
             {
@@ -48,24 +48,23 @@ public object CreateInstance(string typeName)
 
 #if FullNet
                     var assembly = AppDomain.CurrentDomain.Load(new AssemblyName(assemblyName));
-                    return Activator.CreateInstance(assembly.GetType(typeName, true));
 #else
                     var assembly = Context.LoadFromAssemblyName(new AssemblyName(assemblyName));
-                    return Activator.CreateInstance(assembly.GetType(typeName, true));
 #endif
+                    return assembly.GetType(typeName, true);
                 }
 
 #if FullNet
                 foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
                 {
                     var type = assembly.GetType(typeName, false, true);
                     if (type != null)
-                        return Activator.CreateInstance(type);
+                        return type;
                 }
 
                 throw new InvalidOperationException("Could not find the type '" + typeName + "'.");
 #else
-                return Activator.CreateInstance(Type.GetType(typeName, true, true));
+                return Type.GetType(typeName, true, true);
 #endif
             }
             catch (Exception e)
@@ -74,6 +73,11 @@ public object CreateInstance(string typeName)
             }
         }
 
+        public object CreateInstance(string typeName)
+        {
+            return Activator.CreateInstance(GetType(typeName));
+        }
+
         protected void RegisterReferencePaths(IEnumerable<string> referencePaths)
         {
             var allReferencePaths = new List<string>();

src/NSwag.Commands/Commands/SwaggerGeneration/AspNetCore/AspNetCoreToSwaggerCommand.cs

@@ -52,7 +52,7 @@ public class AspNetCoreToSwaggerCommand : SwaggerGeneratorCommandBase<AspNetCore
         public bool NoBuild { get; set; }
 
         [Argument(Name = nameof(Verbose), IsRequired = false, Description = "Print verbose output.")]
-        public bool Verbose { get; set; }
+        public bool Verbose { get; set; } = true;
 
         public override async Task<object> RunAsync(CommandLineProcessor processor, IConsoleHost host)
         {
@@ -185,20 +185,15 @@ public override async Task<object> RunAsync(CommandLineProcessor processor, ICon
 
         protected override async Task<string> RunIsolatedAsync(AssemblyLoader.AssemblyLoader assemblyLoader)
         {
-            Settings.DocumentTemplate = await GetDocumentTemplateAsync();
-            InitializeCustomTypes(assemblyLoader);
-
-            var assemblies = await LoadAssembliesAsync(AssemblyPaths, assemblyLoader).ConfigureAwait(false);
-            var startupType = assemblies.First().ExportedTypes.First(t => t.Name == "Startup"); // TODO: Use .NET Core startup lookup or provide setting
-
-            using (var testServer = new TestServer(new WebHostBuilder().UseStartup(startupType)))
+            using (var testServer = await CreateTestServerAsync(assemblyLoader))
             {
                 // See https://github.com/aspnet/Mvc/issues/5690
 
                 var type = typeof(IApiDescriptionGroupCollectionProvider);
                 var apiDescriptionProvider = (IApiDescriptionGroupCollectionProvider)testServer.Host.Services.GetRequiredService(type);
 
-                var generator = new AspNetCoreToSwaggerGenerator(Settings);
+                var settings = await CreateSettingsAsync(assemblyLoader, testServer.Host);
+                var generator = new AspNetCoreToSwaggerGenerator(settings);
                 var document = await generator.GenerateAsync(apiDescriptionProvider.ApiDescriptionGroups).ConfigureAwait(false);
 
                 return PostprocessDocument(document);

src/NSwag.Commands/Commands/SwaggerGeneration/AspNetCore/AspNetCoreToSwaggerGeneratorCommandEntryPoint.cs

@@ -18,15 +18,14 @@ internal class AspNetCoreToSwaggerGeneratorCommandEntryPoint
     {
         public static void Process(string commandContent, string outputFile, string applicationName)
         {
-            var serviceProvider = GetServiceProvider(applicationName);
-            var apiDescriptionProvider = serviceProvider.GetRequiredService<IApiDescriptionGroupCollectionProvider>();
+            var webHost = GetWebHost(applicationName);
+            var apiDescriptionProvider = webHost.Services.GetRequiredService<IApiDescriptionGroupCollectionProvider>();
 
             var assemblyLoader = new AssemblyLoader.AssemblyLoader();
-
             var command = JsonConvert.DeserializeObject<AspNetCoreToSwaggerCommand>(commandContent);
-            command.InitializeCustomTypes(assemblyLoader);
 
-            var generator = new AspNetCoreToSwaggerGenerator(command.Settings);
+            var settings = Task.Run(async () => await command.CreateSettingsAsync(assemblyLoader, webHost)).GetAwaiter().GetResult();
+            var generator = new AspNetCoreToSwaggerGenerator(settings);
             var document = generator.GenerateAsync(apiDescriptionProvider.ApiDescriptionGroups).GetAwaiter().GetResult();
 
             command.PostprocessDocument(document);
@@ -36,7 +35,7 @@ public static void Process(string commandContent, string outputFile, string appl
             File.WriteAllText(outputFile, document.ToJson());
         }
 
-        private static IServiceProvider GetServiceProvider(string applicationName)
+        private static IWebHost GetWebHost(string applicationName)
         {
             var assemblyName = new AssemblyName(applicationName);
             var assembly = Assembly.Load(assemblyName);
@@ -68,7 +67,7 @@ private static IServiceProvider GetServiceProvider(string applicationName)
 
             if (webHost != null)
             {
-                return webHost.Services;
+                return webHost;
             }
 
             throw new InvalidOperationException($"aspnet2swaggercommand requires the entry point type {entryPointType.FullName} to have " +