Add user authorization service

DrinkRateAPI/Exceptions/Exceptions.cs

@@ -0,0 +1,7 @@
+namespace DrinkRateAPI.Exceptions;
+
+public class DrinkRateException : Exception;
+
+public class NotFoundException : DrinkRateException;
+
+public class UnauthorizedException : DrinkRateException;

DrinkRateAPI/Services/ApplicationUserService.cs

@@ -0,0 +1,21 @@
+using System.Security.Claims;
+using DrinkRateAPI.Contexts;
+using DrinkRateAPI.DbEntities;
+using DrinkRateAPI.Exceptions;
+using Microsoft.EntityFrameworkCore;
+
+namespace DrinkRateAPI.Services;
+
+public class ApplicationUserService(ApplicationDbContext context)
+{
+    private ApplicationDbContext _context = context;
+    public async Task<DbUserProfile> UserProfileByApplicationUserAsync(ClaimsPrincipal identity)
+    {
+        var appUserId = identity.FindFirst(ClaimTypes.NameIdentifier)?.Value;
+        var profile = await _context.UserProfiles
+            .FirstAsync(x => x.ApplicationUserId.ToString() == appUserId)
+            ?? throw new NotFoundException();
+
+        return profile;
+    }
+}