[BUG] csharp-refactor generated client doesn't build in .net core but works with csharp generator

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What’s the version of OpenAPI Generator used?
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• What’s the actual output vs expected output?
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Description

Generated a client using csharp-refactor and it doesn’t build in .NET Core. Getting following errors:

Microsoft (R) Build Engine version 15.8.166+gd4e8d81a88 for .NET Core
Copyright (C) Microsoft Corporation. All rights reserved.

  Restoring packages for /Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj...
  Installing Newtonsoft.Json 12.0.1.
  Installing JsonSubTypes 1.5.1.
  Generating MSBuild file /Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/obj/Org.OpenAPITools.csproj.nuget.g.props.
  Generating MSBuild file /Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/obj/Org.OpenAPITools.csproj.nuget.g.targets.
  Restore completed in 3.26 sec for /Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj.
Api/ActivitiesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CalculationsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CategoriesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CountriesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/HealthCheckApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ImportsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ItemsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ItemSelectorsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/PriceListsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Client/ApiClient.cs(35,48): error CS0234: The type or namespace name 'Serializers' does not exist in the namespace 'RestSharp' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Client/ApiClient.cs(35,83): error CS0234: The type or namespace name 'Deserializers' does not exist in the namespace 'RestSharp' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]

Build FAILED.

Api/ActivitiesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CalculationsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CategoriesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/CountriesApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/HealthCheckApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ImportsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ItemsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/ItemSelectorsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Api/PriceListsApi.cs(17,18): error CS0234: The type or namespace name 'Mime' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Client/ApiClient.cs(35,48): error CS0234: The type or namespace name 'Serializers' does not exist in the namespace 'RestSharp' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
Client/ApiClient.cs(35,83): error CS0234: The type or namespace name 'Deserializers' does not exist in the namespace 'RestSharp' (are you missing an assembly reference?) [/Users/i52017/dev/openapi-gen/output/src/Org.OpenAPITools/Org.OpenAPITools.csproj]
    0 Warning(s)
    11 Error(s)

Time Elapsed 00:00:04.35

openapi-generator version

4.0.0-beta

OpenAPI declaration file content or url

https://api.xactprm.com/pricing/swagger/current/swagger.json

Command line used for generation

openapi-generator generate -i swagger.json -g csharp-refactor -c config.json -o output

Config file:

{
    "targetFramework": "v5.0",
    "netCoreProjectFile": true
}

Steps to reproduce

1. Generate code
2. cd output
3. dotnet build

[chrisdrobison]

Removing RestSharp would be a wonderful move.

[jimschubert]

@nlaveck By dependency, I did mean missing types. In the past, we have been able to workaround similar issues by adding or updating a dependency. We are at a little bit of a disadvantage by using RestSharp. It only supports .NET 4.5.2 and netstandard 2.0, and the Portable version doesn’t have the same API in many cases.

The v5.0 option is confusing as it refers to PCL 5.0 and doesn’t really relate to .NET Standard, aside from maybe being an early attempt at standardization.

In addition to these things, the generator isn’t only used for the built-in templates as many people extend the templates and will need support for the other options.

I have a branch where I’m working through some of these things. I’ll be targeting removal of PCL and UWP support, since users and refer to openapi-generator 3.3.4 if these are needed. I just need to figure a way to expose warnings when users are targeting built-in templates wuth options that aren’t supported because of our dependency on RestSharp.

My long-term goal is to remove RestSharp and possibly all third-party dependencies, allowing the templates to be generic enough to support all framework (or netstandard) versions targeted by the generator.