C# Example to Generate an Access Token

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Threading.Tasks;

namespace ClientCredentialsFlowExample
{
    internal class Program
    {
        public static async Task Main(string[] args)
        {
            string tokenEndpoint = "https://identity.nexar.com/connect/token";
            string clientId = "YOUR_CLIENT_ID";
            string clientSecret = "YOUR_CLIENT_SECRET";

            var httpClient = new HttpClient();

            var request = new HttpRequestMessage(HttpMethod.Post, tokenEndpoint);
            request.Headers.Authorization = CreateBasicAuthenticationHeader(clientId, clientSecret);
            request.Content = new FormUrlEncodedContent(
                new Dictionary<string, string>
                {
                    { "grant_type", "client_credentials" },
                    { "scope", "supply.domain" }
                });

            var response = await httpClient.SendAsync(request);
            response.EnsureSuccessStatusCode();

            string content = await response.Content.ReadAsStringAsync();
            var respObj = JsonSerializer.Deserialize<TokenResponse>(content);
            string accessToken = respObj.AccessToken;

            Console.WriteLine($"Access token: {accessToken}");
        }

        private static AuthenticationHeaderValue CreateBasicAuthenticationHeader(string clientId, string clientSecret)
        {
            string creds = $"{clientId}:{clientSecret}";
            string encodedCreds = Convert.ToBase64String(Encoding.UTF8.GetBytes(creds));
            return new AuthenticationHeaderValue("Basic", encodedCreds);
        }
    }

    internal class TokenResponse
    {
        [JsonPropertyName("access_token")]
        public string AccessToken { get; set; }

        [JsonPropertyName("expires_in")]
        public int ExpiresIn { get; set; }

        [JsonPropertyName("scope")]
        public string Scope { get; set; }
    }
}