snowflake-connector-net: SNOW-352097: ExternalBrowser authentication type does not work for .NET Core projects on Windows, Linux or Mac

Issue Description

When using ExternalBrowser authentication type, URL to the SSO provider is constructed and a browser window is opened using default OS browser. The code to start it is in Snowflake.Data.Core.Authenticator.ExternalBrowserAuthenticator.StartBrowser https://github.com/snowflakedb/snowflake-connector-net/blob/master/Snowflake.Data/Core/Authenticator/ExternalBrowserAuthenticator.cs#L156-L174

        private static void StartBrowser(string url)
        {
            // The following code is learnt from https://brockallen.com/2016/09/24/process-start-for-urls-on-net-core/
#if NETFRAMEWORK
            // .net standard would pass here
            Process.Start(url);
#else
            // hack because of this: https://github.com/dotnet/corefx/issues/10361
            if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
            {
                url = url.Replace("&", "^&");
                Process.Start(new ProcessStartInfo("cmd", $"/c start {url}") { CreateNoWindow = true });
            }
            else
            {
                throw new SnowflakeDbException(SFError.UNSUPPORTED_PLATFORM);
            }
#endif
        }

The logic of the https://github.com/snowflakedb/snowflake-connector-net/blob/master/Snowflake.Data/Core/Authenticator/ExternalBrowserAuthenticator.cs#L159 is incorrect.

The NETFRAMEWORK preprocessor symbol is used to conditionally compile in Process.Start(url) for what the comments suggest are .NET Standard.

#if NETFRAMEWORK
            // .net standard would pass here
            Process.Start(url);

However, per https://docs.microsoft.com/en-us/dotnet/standard/frameworks#how-to-specify-a-target-framework, NETFRAMEWORK preprocessor symbol is for “.NET Framework”, not 'NET Standard".

Looking at Result of Compilation

When compiled, the DLL in the C:\snowflake\snowflake-connector-net\Snowflake.Data\bin\Release\net472\Snowflake.Data.dll as well as in the public nuget package C:\Users\Daniel\Downloads\snowflake.data.2.0.0\lib\net472\Snowflake.Data.dll that is targeting .NET Full Framework for Windows Only desktops, which works fine on Windows:

// Snowflake.Data.Core.Authenticator.ExternalBrowserAuthenticator
using System.Diagnostics;

private static void StartBrowser(string url)
{
    Process.Start(url);
}

Looking at the DLL that targets .NET Core in C:\snowflake\snowflake-connector-net\Snowflake.Data\bin\Release\netstandard2.0\Snowflake.Data.dll and in C:\Users\Daniel\Downloads\snowflake.data.2.0.0\lib\netstandard2.0\Snowflake.Data.dll, that would be used by code running on Mac and Linux, we can see that code that could only run on Windows (and it does run beautifully there), but throws an SnowflakeDbException for Mac and Linux:

// Snowflake.Data.Core.Authenticator.ExternalBrowserAuthenticator
using Snowflake.Data.Client;
using System.Diagnostics;
using System.Runtime.InteropServices;

private static void StartBrowser(string url)
{
    if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
    {
        url = url.Replace("&", "^&");
        Process.Start(new ProcessStartInfo("cmd", $"/c start {url}")
        {
            CreateNoWindow = true
        });
        return;
    }
    throw new SnowflakeDbException(SFError.UNSUPPORTED_PLATFORM);
}

Possible Solution 1

This seems like an honest mistake, and can most easily be fixed by changing to correct preprocessor symbol NETSTANDARD2_1 or better yet NET:

#if NET
            // .net standard would pass here
            Process.Start(url);

Possible Solution 2

Better yet, change the code to explicitly address 3 different OS versions. In fact https://brockallen.com/2016/09/24/process-start-for-urls-on-net-core/ that is mentioned in comments does just that.