Im using dotnet webapi 6 with the new official library from openai,

https://github.com/openai/openai-dotnet

What I’m trying to do, is to use a local image file to openai,
The file isn’t under wwwroot, but under “backend/assets/1.jpg”.

I’ve wrote a basic service to setup all the information needed in order to send a request to openai,
But the problem is that I’m not able to send the image,
I keep getting errors like “url is too long” or “invalid image”,

here is my code:
OpenAiService:

using OpenAI.Chat;


namespace backend.Services
{
    public class OpenAiService
    {
        private readonly ChatClient _chatClient;
        private readonly ChatCompletionOptions _options;

        public OpenAiService(IConfiguration configuration)
        {
            var apiKey = configuration.GetValue<string>("OpenAI:Key");
            _chatClient = new ChatClient("gpt-4o", apiKey);
            _options = new ChatCompletionOptions()
            {
                MaxTokens = 300,
            };
        }

        public async Task<string> ExtractListOfItems()
        {
            var imagePath = Path.Combine(Directory.GetCurrentDirectory(), "Assets", "1.jpg");
            var localUrl = $"https://localhost:7068/assets/{Path.GetFileName(imagePath)}";
            
            var messages = new List<ChatMessage>
            {
                new UserChatMessage(new List<ChatMessageContentPart>
                {
                    ChatMessageContentPart.CreateTextMessageContentPart("Extract the items from the following image and return a list of items including prices and amount."),
                    ChatMessageContentPart.CreateImageMessageContentPart(new Uri(localUrl))
                })
            };

            var completion = await _chatClient.CompleteChatAsync(messages, _options);
            return completion.Value.ToString();
        }

        
    }
}

demo controller for testing:

using Microsoft.AspNetCore.Mvc;
using System.Threading.Tasks;
using backend.Services;
using OpenAI;
using OpenAI.Chat;

namespace backend.Controllers;

[ApiController]
[Route("[controller]")]
public class OpenAiDemoController : ControllerBase
{
    private readonly OpenAiService _openAiService;

    public OpenAiDemoController(OpenAiService openAiService)
    {
        _openAiService = openAiService;
    }
    
    [HttpPost]
    [Route("extract-items")]
    public async Task<IActionResult> CompleteSentence()
    {
        var completion = await _openAiService.ExtractListOfItems();
        return Ok(completion);
    }
    
}

program.cs file

using backend.Configurations;
using backend.Services;
using Microsoft.Extensions.FileProviders;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.Configure<OpenAiConfig>(builder.Configuration.GetSection("OpenAI"));

//add services
builder.Services.AddSingleton<OpenAiService>();

builder.Services.AddControllers();
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();


// builder.Services.AddScoped<IOpenAiService, OpenAiService>();


builder.Services.AddCors(opt =>
{
    opt.AddPolicy("AllowAll", builder =>
    {
        builder.AllowAnyOrigin()
            .AllowAnyMethod()
            .AllowAnyHeader();
    });
});


var app = builder.Build();

app.UseStaticFiles(new StaticFileOptions
{
    FileProvider = new PhysicalFileProvider(
        Path.Combine(builder.Environment.ContentRootPath, "Assets")),
    RequestPath = "/assets"
});

app.UseStaticFiles(); // This serves files from wwwroot

app.UseStaticFiles(new StaticFileOptions
{
    FileProvider = new PhysicalFileProvider(
        Path.Combine(builder.Environment.ContentRootPath, "Assets")),
    RequestPath = "/assets"
});
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseCors("AllowAll");

app.UseAuthorization();

app.MapControllers();

app.Run();