Add project files.

Features/Puzzle/Get/GetPuzzleEndpoint.cs

@@ -0,0 +1,83 @@
+using ConnectionsAPI.Database;
+using ConnectionsAPI.Models;
+using FluentValidation;
+using LazyCache;
+using Microsoft.EntityFrameworkCore;
+using System.Text.RegularExpressions;
+
+namespace ConnectionsAPI.Features.Puzzle.Get
+{
+    public record GetPuzzleEndpointRequest(string PuzzleDate);
+
+    public partial class GetPuzzleEndpointRequestValidator : Validator<GetPuzzleEndpointRequest>
+    {
+        [GeneratedRegex("^\\d{4}-\\d{2}-\\d{2}$", RegexOptions.IgnoreCase)]
+        private static partial Regex PrintDateGeneratedRegex();
+
+        public GetPuzzleEndpointRequestValidator()
+        {
+            RuleFor(x => x.PuzzleDate)
+                .NotEmpty().WithMessage("Puzzle date is required")
+                .Must(x => PrintDateGeneratedRegex().IsMatch(x)).WithMessage("Puzzle date must be in the format yyyy-MM-dd");
+        }
+    }
+
+    public class GetPuzzleEndpoint(ConnectionsContext db, ILogger<GetPuzzleEndpoint> logger, IAppCache cache) : Endpoint<GetPuzzleEndpointRequest, PuzzleDTO>
+    {
+        private readonly ConnectionsContext _db = db;
+        private readonly ILogger<GetPuzzleEndpoint> _logger = logger;
+        private readonly IAppCache _cache = cache;
+
+        public override void Configure()
+        {
+            Get("/{PuzzleDate}.json");
+            AllowAnonymous();
+            DontThrowIfValidationFails();
+        }
+
+        public override async Task HandleAsync(GetPuzzleEndpointRequest req, CancellationToken ct)
+        {
+            // default to 404 if validation fails
+            if (ValidationFailed)
+            {
+                _logger.LogError("Validation error. {path} {pathBase}", HttpContext.Request.Path, HttpContext.Request.PathBase);
+                await SendNotFoundAsync(ct);
+                return;
+            }
+
+            // get response from cache
+            var response = await _cache.GetOrAddAsync($"Puzzle:{req.PuzzleDate}",
+                                                      () => { return GetResponseForCache(req.PuzzleDate); },
+                                                      DateTimeOffset.UtcNow.AddMinutes(5));
+
+            // if not found, done here
+            if (response == null)
+            {
+                await SendNotFoundAsync(ct);
+                return;
+            }
+
+            // done
+            await SendAsync(response, cancellation: ct);
+        }
+
+        private async Task<PuzzleDTO?> GetResponseForCache(string printDate)
+        {
+            // query for the puzzle
+            var puzzle = await _db.Puzzles
+                .Include(x => x.Categories)
+                .ThenInclude(x => x.PuzzleCards)
+                .AsNoTracking()
+                .FirstOrDefaultAsync(x => x.PrintDate == printDate);
+
+            // if not found, we're done here
+            if (puzzle == null)
+            {
+                return null;
+            }
+
+            // if found, map
+            return PuzzleDTO.FromEntity(puzzle);
+        }
+    }
+}