exception when trying to use Vertex Express mode with platform adapter

[clarity99]

I'm trying to use IChatClient with Vertex AI Express mode.
I thought this would work:

var adapter = new VertextPlatformAdapter(expressMode: true, apiKey: key);

client = (IChatClient)new GenerativeAIChatClient(adapter,
                    selectedModel);

however, this throws an exception - No configuration found for Vertex AI.

Looking at the sourcecode, it tries to load credentials from the file if projectId is null.

Am I doing something wrong? Looking at example for express mode without IChatClient, I thought it should work:
var vertexAIClient = new VertexAI(apiKey: apiKey, expressMode: true);

However, even if I just run this example, (with VertexAI constructor) I get the same exception, as it seems to call the platformadapter anyway:

robRezCore.Components.Pages.NotesAI: Error: Error while calling AI. ex:System.Exception: No configuration found for Vertex AI.
   at VertextPlatformAdapter..ctor(String projectId, String region, Boolean expressMode, String apiKey, String accessToken, String apiVersion, IGoogleAuthenticator authenticator, String credentialsFile, Boolean validateAccessToken, ILogger logger) in /_/src/GenerativeAI/Platforms/VertextPlatformAdapter.cs:line 137
   at GenerativeAI.VertexAI..ctor(String projectId, String region, String accessToken, Boolean expressMode, String apiKey, String apiVersion, HttpClient httpClient, IGoogleAuthenticator authenticator, ILogger logger) in /_/src/GenerativeAI/Platforms/VertexAI.cs:line 46

[clarity99]

I've made a quick fix for this in #62 PR. It seems to work, but not sure if it breaks something else.

[gunpal5]

Thank you I will check the project before publishing it.

[clarity99]

hi @gunpal5 , just wondering when an updated nuget package for this will come out? thanks!