Implement all car endpoints

src/WebApi/Authentication/UserAccessor.cs

@@ -0,0 +1,78 @@
+using Microsoft.Extensions.Options;
+using System.Diagnostics.CodeAnalysis;
+using System.Security.Claims;
+
+namespace Vegasco.WebApi.Authentication;
+
+public sealed class UserAccessor
+{
+	private readonly IHttpContextAccessor _httpContextAccessor;
+	private readonly IOptions<JwtOptions> _jwtOptions;
+
+	/// <summary>
+	/// Stores the username upon first retrieval
+	/// </summary>
+	private string? _cachedUsername;
+
+	/// <summary>
+	/// Stores the id upon first retrieval
+	/// </summary>
+	private string? _cachedId;
+
+	public UserAccessor(IHttpContextAccessor httpContextAccessor, IOptions<JwtOptions> jwtOptions)
+	{
+		_httpContextAccessor = httpContextAccessor;
+		_jwtOptions = jwtOptions;
+	}
+
+	public string GetUsername()
+	{
+		if (string.IsNullOrEmpty(_cachedUsername))
+		{
+			_cachedUsername = GetClaimValue(_jwtOptions.Value.NameClaimType ?? ClaimTypes.Name);
+		}
+
+		return _cachedUsername;
+	}
+
+	public string GetUserId()
+	{
+		if (string.IsNullOrEmpty(_cachedId))
+		{
+			_cachedId = GetClaimValue(ClaimTypes.NameIdentifier);
+		}
+
+		return _cachedId;
+	}
+
+	private string GetClaimValue(string claimType)
+	{
+		var httpContext = _httpContextAccessor.HttpContext;
+
+		if (httpContext is null)
+		{
+			ThrowForMissingHttpContext();
+		}
+
+		var claimValue = httpContext.User.FindFirstValue(claimType);
+
+		if (string.IsNullOrWhiteSpace(claimValue))
+		{
+			ThrowForMissingClaim(claimType);
+		}
+
+		return claimValue;
+	}
+
+	[DoesNotReturn]
+	private static void ThrowForMissingHttpContext()
+	{
+		throw new InvalidOperationException("No HttpContext available.");
+	}
+
+	[DoesNotReturn]
+	private static void ThrowForMissingClaim(string claimType)
+	{
+		throw new InvalidOperationException($"No claim of type '{claimType}' found on the current user.");
+	}
+}