NullReferenceException on generating clients

[galadril]

I'm getting NullReferenceExceptions on generating some client code (CSharp and TypeScript).

I tried to consume the latest v2 api of Searoutes: https://developer.searoutes.com/api/v2.yaml

But i get the next exception:

System.InvalidOperationException: Error while rendering Liquid template CSharp/Client.Class: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object.

Runtime: NetCore31 at NSwag.CodeGeneration.Models.OperationModelBase2.get_UnwrappedResultType() in C:\projects\nswag\src\NSwag.CodeGeneration\Models\OperationModelBase.cs:line 120 at NSwag.CodeGeneration.CSharp.Models.CSharpOperationModel.get_SyncResultType() in C:\projects\nswag\src\NSwag.CodeGeneration.CSharp\Models\CSharpOperationModel.cs:line 127 at NSwag.CodeGeneration.CSharp.Models.CSharpOperationModel.get_ResultType() in C:\projects\nswag\src\NSwag.CodeGeneration.CSharp\Models\CSharpOperationModel.cs:line 136 --- End of inner exception stack trace --- at DotLiquid.Context.HandleError(Exception ex) at DotLiquid.Block.RenderAll(List1 list, Context context, TextWriter result) at DotLiquid.Block.Render(Context context, TextWriter result) at DotLiquid.Document.Render(Context context, TextWriter result) at DotLiquid.Template.RenderInternal(TextWriter result, RenderParameters parameters) at DotLiquid.Template.Render(TextWriter writer, RenderParameters parameters) at DotLiquid.Template.Render(RenderParameters parameters) at NJsonSchema.CodeGeneration.DefaultTemplateFactory.LiquidTemplate.Render() ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object. at NSwag.CodeGeneration.Models.OperationModelBase2.get_UnwrappedResultType() in C:\projects\nswag\src\NSwag.CodeGeneration\Models\OperationModelBase.cs:line 120 at NSwag.CodeGeneration.CSharp.Models.CSharpOperationModel.get_SyncResultType() in C:\projects\nswag\src\NSwag.CodeGeneration.CSharp\Models\CSharpOperationModel.cs:line 127 at NSwag.CodeGeneration.CSharp.Models.CSharpOperationModel.get_ResultType() in C:\projects\nswag\src\NSwag.CodeGeneration.CSharp\Models\CSharpOperationModel.cs:line 136 --- End of inner exception stack trace --- at DotLiquid.Context.HandleError(Exception ex) at DotLiquid.Block.RenderAll(List1 list, Context context, TextWriter result) at DotLiquid.Block.Render(Context context, TextWriter result) at DotLiquid.Document.Render(Context context, TextWriter result) at DotLiquid.Template.RenderInternal(TextWriter result, RenderParameters parameters) at DotLiquid.Template.Render(TextWriter writer, RenderParameters parameters) at DotLiquid.Template.Render(RenderParameters parameters) at NJsonSchema.CodeGeneration.DefaultTemplateFactory.LiquidTemplate.Render() --- End of inner exception stack trace --- at NJsonSchema.CodeGeneration.DefaultTemplateFactory.LiquidTemplate.Render() at NJsonSchema.CodeGeneration.CodeArtifact..ctor(String typeName, CodeArtifactType type, CodeArtifactLanguage language, CodeArtifactCategory category, ITemplate template) at NSwag.CodeGeneration.CSharp.CSharpClientGenerator.GenerateClientTypes(String controllerName, String controllerClassName, IEnumerable1 operations)+MoveNext() in C:\projects\nswag\src\NSwag.CodeGeneration.CSharp\CSharpClientGenerator.cs:line 68 at System.Collections.Generic.List1.InsertRange(Int32 index, IEnumerable1 collection) at NSwag.CodeGeneration.ClientGeneratorBase3.GenerateAllClientTypes() in C:\projects\nswag\src\NSwag.CodeGeneration\ClientGeneratorBase.cs:line 112 at NSwag.CodeGeneration.ClientGeneratorBase`3.GenerateFile(ClientGeneratorOutputType outputType) in C:\projects\nswag\src\NSwag.CodeGeneration\ClientGeneratorBase.cs:line 73 at NSwag.Commands.CodeGeneration.SwaggerToCSharpClientCommand.b__92_0() in C:\projects\nswag\src\NSwag.Commands\Commands\CodeGeneration\OpenApiToCSharpClientCommand.cs:line 265 at NSwag.Commands.CodeGeneration.SwaggerToCSharpClientCommand.RunAsync() in C:\projects\nswag\src\NSwag.Commands\Commands\CodeGeneration\OpenApiToCSharpClientCommand.cs:line 251 at NSwag.Commands.CodeGeneration.SwaggerToCSharpClientCommand.RunAsync(CommandLineProcessor processor, IConsoleHost host) in C:\projects\nswag\src\NSwag.Commands\Commands\CodeGeneration\OpenApiToCSharpClientCommand.cs:line 240 at NSwag.Commands.NSwagDocument.ExecuteAsync() in C:\projects\nswag\src\NSwag.Commands\NSwagDocument.cs:line 85 at NSwag.Commands.Document.ExecuteDocumentCommand.ExecuteDocumentAsync(IConsoleHost host, String filePath) in C:\projects\nswag\src\NSwag.Commands\Commands\Document\ExecuteDocumentCommand.cs:line 86 at NSwag.Commands.Document.ExecuteDocumentCommand.RunAsync(CommandLineProcessor processor, IConsoleHost host) in C:\projects\nswag\src\NSwag.Commands\Commands\Document\ExecuteDocumentCommand.cs:line 32 at NConsole.CommandLineProcessor.ProcessSingleAsync(String[] args, Object input) at NConsole.CommandLineProcessor.ProcessAsync(String[] args, Object input) at NConsole.CommandLineProcessor.Process(String[] args, Object input) at NSwag.Commands.NSwagCommandProcessor.Process(String[] args) in C:\projects\nswag\src\NSwag.Commands\NSwagCommandProcessor.cs:line 56

[petrkoutnycz]

Any progress so far? I've come across the same issue recently.

[janseris]

I am getting this error for this yaml openapi_sanitized yaml.txt

Generated by Quarkus framework in Java (don't know the details).

[janseris]

@petrkoutnycz I found out what was the issue (for my case). The method name (get_UnwrappedResultType()) suggests that the problem is in return type and it was right.

This was errornenous:

"content": {
  "text/plain" : { }
}

While this works.

"content": {
  "text/plain" : {
    "schema" : {
      "type" : "string"
    }
  }
}

Btw this https://editor.swagger.io/ generator did not have a problem with less information in the response content. But NSwag is built-in for Visual Studio.