[AZ-310] [AZ-311] Route tile endpoints through ITileService

Move cache+DB+download logic for /tiles/{z}/{x}/{y} and
/api/satellite/tiles/latlon out of Program.cs into TileService.
Endpoints now inject only ITileService + ILogger. Service owns
IMemoryCache (1h absolute / 30min sliding preserved). Added
TileBytes DTO; ITileService gains GetOrDownloadTileAsync and
DownloadAndStoreSingleTileAsync. 5 new unit tests cover cache
hit, repo hit, downloader fallback, and AZ-311 happy + error.

Build clean (0/0), unit suite 40/40. Resolves architecture
baseline F3 in code (docs handled by AZ-315).

Co-authored-by: Cursor <cursoragent@cursor.com>

SatelliteProvider.Api/Program.cs

@@ -1,15 +1,12 @@
 using System.ComponentModel.DataAnnotations;
 using Microsoft.AspNetCore.Mvc;
-using Microsoft.Extensions.Caching.Memory;
 using Microsoft.OpenApi.Models;
 using Swashbuckle.AspNetCore.SwaggerGen;
 using SatelliteProvider.DataAccess;
-using SatelliteProvider.DataAccess.Models;
 using SatelliteProvider.DataAccess.Repositories;
 using SatelliteProvider.Common.Configs;
 using SatelliteProvider.Common.DTO;
 using SatelliteProvider.Common.Interfaces;
-using SatelliteProvider.Common.Utils;
 using SatelliteProvider.Services;
 using Serilog;
 
@@ -138,63 +135,14 @@ app.MapGet("/api/satellite/route/{id:guid}", GetRoute)
 
 app.Run();
 
-async Task<IResult> ServeTile(int z, int x, int y, HttpContext httpContext, ITileRepository tileRepository, ISatelliteDownloader downloader, IMemoryCache cache, ILogger<Program> logger)
+async Task<IResult> ServeTile(int z, int x, int y, HttpContext httpContext, ITileService tileService, ILogger<Program> logger)
 {
-    var cacheKey = $"tile_{z}_{x}_{y}";
     try
     {
-        if (cache.TryGetValue(cacheKey, out byte[]? cachedBytes) && cachedBytes != null)
+        var tile = await tileService.GetOrDownloadTileAsync(z, x, y, httpContext.RequestAborted);
-        {
+        httpContext.Response.Headers.CacheControl = $"public, max-age={(long)tile.MaxAge.TotalSeconds}";
-            httpContext.Response.Headers.CacheControl = "public, max-age=86400";
+        httpContext.Response.Headers.ETag = tile.ETag;
-            httpContext.Response.Headers.ETag = $"\"{z}_{x}_{y}\"";
+        return Results.Bytes(tile.Bytes, tile.ContentType);
-            return Results.Bytes(cachedBytes, "image/jpeg");
-        }
-
-        string? filePath = null;
-
-        var tile = await tileRepository.GetByTileCoordinatesAsync(z, x, y);
-        if (tile != null && File.Exists(tile.FilePath))
-        {
-            filePath = tile.FilePath;
-        }
-        else
-        {
-            var tileCenter = GeoUtils.TileToWorldPos(x, y, z);
-            var downloadedTile = await downloader.DownloadSingleTileAsync(tileCenter.Lat, tileCenter.Lon, z);
-
-            var now = DateTime.UtcNow;
-            var tileEntity = new TileEntity
-            {
-                Id = Guid.NewGuid(),
-                TileZoom = z,
-                TileX = downloadedTile.X,
-                TileY = downloadedTile.Y,
-                Latitude = downloadedTile.CenterLatitude,
-                Longitude = downloadedTile.CenterLongitude,
-                TileSizeMeters = downloadedTile.TileSizeMeters,
-                TileSizePixels = 256,
-                ImageType = "jpg",
-                MapsVersion = $"downloaded_{now:yyyy-MM-dd}",
-                Version = now.Year,
-                FilePath = downloadedTile.FilePath,
-                CreatedAt = now,
-                UpdatedAt = now
-            };
-
-            await tileRepository.InsertAsync(tileEntity);
-            filePath = tileEntity.FilePath;
-        }
-
-        var bytes = await File.ReadAllBytesAsync(filePath);
-        cache.Set(cacheKey, bytes, new MemoryCacheEntryOptions
-        {
-            AbsoluteExpirationRelativeToNow = TimeSpan.FromHours(1),
-            SlidingExpiration = TimeSpan.FromMinutes(30)
-        });
-
-        httpContext.Response.Headers.CacheControl = "public, max-age=86400";
-        httpContext.Response.Headers.ETag = $"\"{z}_{x}_{y}\"";
-        return Results.Bytes(bytes, "image/jpeg");
     }
     catch (Exception ex)
     {
@@ -203,51 +151,26 @@ async Task<IResult> ServeTile(int z, int x, int y, HttpContext httpContext, ITil
     }
 }
 
-async Task<IResult> GetTileByLatLon([FromQuery] double Latitude, [FromQuery] double Longitude, [FromQuery] int ZoomLevel, ISatelliteDownloader downloader, ITileRepository tileRepository, ILogger<Program> logger)
+async Task<IResult> GetTileByLatLon([FromQuery] double Latitude, [FromQuery] double Longitude, [FromQuery] int ZoomLevel, ITileService tileService, ILogger<Program> logger)
 {
     try
     {
-        var downloadedTile = await downloader.DownloadSingleTileAsync(
+        var tile = await tileService.DownloadAndStoreSingleTileAsync(Latitude, Longitude, ZoomLevel);
-            Latitude,
-            Longitude,
-            ZoomLevel);
-
-        var now = DateTime.UtcNow;
-        var currentVersion = now.Year;
-        var tileEntity = new TileEntity
-        {
-            Id = Guid.NewGuid(),
-            TileZoom = downloadedTile.ZoomLevel,
-            TileX = downloadedTile.X,
-            TileY = downloadedTile.Y,
-            Latitude = downloadedTile.CenterLatitude,
-            Longitude = downloadedTile.CenterLongitude,
-            TileSizeMeters = downloadedTile.TileSizeMeters,
-            TileSizePixels = 256,
-            ImageType = "jpg",
-            MapsVersion = $"downloaded_{now:yyyy-MM-dd}",
-            Version = currentVersion,
-            FilePath = downloadedTile.FilePath,
-            CreatedAt = now,
-            UpdatedAt = now
-        };
-
-        await tileRepository.InsertAsync(tileEntity);
 
         var response = new DownloadTileResponse
         {
-            Id = tileEntity.Id,
+            Id = tile.Id,
-            ZoomLevel = tileEntity.TileZoom,
+            ZoomLevel = tile.TileZoom,
-            Latitude = tileEntity.Latitude,
+            Latitude = tile.Latitude,
-            Longitude = tileEntity.Longitude,
+            Longitude = tile.Longitude,
-            TileSizeMeters = tileEntity.TileSizeMeters,
+            TileSizeMeters = tile.TileSizeMeters,
-            TileSizePixels = tileEntity.TileSizePixels,
+            TileSizePixels = tile.TileSizePixels,
-            ImageType = tileEntity.ImageType,
+            ImageType = tile.ImageType,
-            MapsVersion = tileEntity.MapsVersion,
+            MapsVersion = tile.MapsVersion,
-            Version = currentVersion,
+            Version = tile.Version,
-            FilePath = tileEntity.FilePath,
+            FilePath = tile.FilePath,
-            CreatedAt = tileEntity.CreatedAt,
+            CreatedAt = tile.CreatedAt,
-            UpdatedAt = tileEntity.UpdatedAt
+            UpdatedAt = tile.UpdatedAt
         };
 
         return Results.Ok(response);

SatelliteProvider.Common/DTO/TileBytes.cs

@@ -0,0 +1,3 @@
+namespace SatelliteProvider.Common.DTO;
+
+public record TileBytes(byte[] Bytes, string ContentType, string ETag, TimeSpan MaxAge);

SatelliteProvider.Common/Interfaces/ITileService.cs

@@ -7,5 +7,7 @@ public interface ITileService
     Task<List<TileMetadata>> DownloadAndStoreTilesAsync(double latitude, double longitude, double sizeMeters, int zoomLevel, CancellationToken cancellationToken = default);
     Task<TileMetadata?> GetTileAsync(Guid id);
     Task<IEnumerable<TileMetadata>> GetTilesByRegionAsync(double latitude, double longitude, double sizeMeters, int zoomLevel);
+    Task<TileBytes> GetOrDownloadTileAsync(int z, int x, int y, CancellationToken cancellationToken = default);
+    Task<TileMetadata> DownloadAndStoreSingleTileAsync(double latitude, double longitude, int zoomLevel, CancellationToken cancellationToken = default);
 }
 

SatelliteProvider.Services/SatelliteProvider.Services.csproj

@@ -7,6 +7,7 @@
     </PropertyGroup>
 
     <ItemGroup>
+      <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="9.0.10" />
       <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="9.0.10" />
       <PackageReference Include="Microsoft.Extensions.Http" Version="9.0.10" />
       <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="9.0.10" />

SatelliteProvider.Services/TileService.cs

@@ -1,6 +1,8 @@
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Logging;
 using SatelliteProvider.Common.DTO;
 using SatelliteProvider.Common.Interfaces;
+using SatelliteProvider.Common.Utils;
 using SatelliteProvider.DataAccess.Models;
 using SatelliteProvider.DataAccess.Repositories;
 
@@ -8,17 +10,25 @@ namespace SatelliteProvider.Services;
 
 public class TileService : ITileService
 {
+    private static readonly TimeSpan TileCacheAbsolute = TimeSpan.FromHours(1);
+    private static readonly TimeSpan TileCacheSliding = TimeSpan.FromMinutes(30);
+    private static readonly TimeSpan TileResponseMaxAge = TimeSpan.FromDays(1);
+    private const string TileImageContentType = "image/jpeg";
+
     private readonly ISatelliteDownloader _downloader;
     private readonly ITileRepository _tileRepository;
+    private readonly IMemoryCache _cache;
     private readonly ILogger<TileService> _logger;
 
     public TileService(
         ISatelliteDownloader downloader,
         ITileRepository tileRepository,
+        IMemoryCache cache,
         ILogger<TileService> logger)
     {
         _downloader = downloader;
         _tileRepository = tileRepository;
+        _cache = cache;
         _logger = logger;
     }
 
@@ -48,8 +58,6 @@ public class TileService : ITileService
             cancellationToken);
         
         var result = new List<TileMetadata>();
-        int reusedCount = existingTilesList.Count;
-        int downloadedCount = downloadedTiles.Count;
         
         foreach (var existingTile in existingTilesList)
         {
@@ -58,26 +66,7 @@ public class TileService : ITileService
         
         foreach (var downloadedTile in downloadedTiles)
         {
-            var now = DateTime.UtcNow;
+            var tileEntity = BuildTileEntity(downloadedTile, currentVersion);
-            
-            var tileEntity = new TileEntity
-            {
-                Id = Guid.NewGuid(),
-                TileZoom = downloadedTile.ZoomLevel,
-                TileX = downloadedTile.X,
-                TileY = downloadedTile.Y,
-                Latitude = downloadedTile.CenterLatitude,
-                Longitude = downloadedTile.CenterLongitude,
-                TileSizeMeters = downloadedTile.TileSizeMeters,
-                TileSizePixels = 256,
-                ImageType = "jpg",
-                MapsVersion = $"downloaded_{now:yyyy-MM-dd}",
-                Version = currentVersion,
-                FilePath = downloadedTile.FilePath,
-                CreatedAt = now,
-                UpdatedAt = now
-            };
-
             await _tileRepository.InsertAsync(tileEntity);
             result.Add(MapToMetadata(tileEntity));
         }
@@ -101,6 +90,75 @@ public class TileService : ITileService
         return tiles.Select(MapToMetadata);
     }
 
+    public async Task<TileBytes> GetOrDownloadTileAsync(int z, int x, int y, CancellationToken cancellationToken = default)
+    {
+        var cacheKey = $"tile_{z}_{x}_{y}";
+        var etag = $"\"{z}_{x}_{y}\"";
+
+        if (_cache.TryGetValue(cacheKey, out byte[]? cachedBytes) && cachedBytes != null)
+        {
+            return new TileBytes(cachedBytes, TileImageContentType, etag, TileResponseMaxAge);
+        }
+
+        string filePath;
+        var existing = await _tileRepository.GetByTileCoordinatesAsync(z, x, y);
+        if (existing != null && File.Exists(existing.FilePath))
+        {
+            filePath = existing.FilePath;
+        }
+        else
+        {
+            var tileCenter = GeoUtils.TileToWorldPos(x, y, z);
+            var downloaded = await _downloader.DownloadSingleTileAsync(tileCenter.Lat, tileCenter.Lon, z, cancellationToken);
+            var entity = BuildTileEntity(downloaded, DateTime.UtcNow.Year);
+            await _tileRepository.InsertAsync(entity);
+            filePath = entity.FilePath;
+        }
+
+        var bytes = await File.ReadAllBytesAsync(filePath, cancellationToken);
+        _cache.Set(cacheKey, bytes, new MemoryCacheEntryOptions
+        {
+            AbsoluteExpirationRelativeToNow = TileCacheAbsolute,
+            SlidingExpiration = TileCacheSliding
+        });
+
+        return new TileBytes(bytes, TileImageContentType, etag, TileResponseMaxAge);
+    }
+
+    public async Task<TileMetadata> DownloadAndStoreSingleTileAsync(
+        double latitude,
+        double longitude,
+        int zoomLevel,
+        CancellationToken cancellationToken = default)
+    {
+        var downloaded = await _downloader.DownloadSingleTileAsync(latitude, longitude, zoomLevel, cancellationToken);
+        var entity = BuildTileEntity(downloaded, DateTime.UtcNow.Year);
+        await _tileRepository.InsertAsync(entity);
+        return MapToMetadata(entity);
+    }
+
+    private static TileEntity BuildTileEntity(DownloadedTileInfoV2 downloaded, int currentVersion)
+    {
+        var now = DateTime.UtcNow;
+        return new TileEntity
+        {
+            Id = Guid.NewGuid(),
+            TileZoom = downloaded.ZoomLevel,
+            TileX = downloaded.X,
+            TileY = downloaded.Y,
+            Latitude = downloaded.CenterLatitude,
+            Longitude = downloaded.CenterLongitude,
+            TileSizeMeters = downloaded.TileSizeMeters,
+            TileSizePixels = 256,
+            ImageType = "jpg",
+            MapsVersion = $"downloaded_{now:yyyy-MM-dd}",
+            Version = currentVersion,
+            FilePath = downloaded.FilePath,
+            CreatedAt = now,
+            UpdatedAt = now
+        };
+    }
+
     private static TileMetadata MapToMetadata(TileEntity entity)
     {
         return new TileMetadata

SatelliteProvider.Tests/InfrastructureTests.cs

@@ -1,4 +1,5 @@
 using FluentAssertions;
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Logging.Abstractions;
 using Moq;
 using SatelliteProvider.Common.DTO;
@@ -60,10 +61,11 @@ public class InfrastructureTests
         // Arrange
         var downloader = new Mock<ISatelliteDownloader>().Object;
         var tileRepo = new Mock<ITileRepository>().Object;
+        var cache = new MemoryCache(new MemoryCacheOptions());
         var logger = NullLogger<TileService>.Instance;
 
         // Act
-        var service = new TileService(downloader, tileRepo, logger);
+        var service = new TileService(downloader, tileRepo, cache, logger);
 
         // Assert
         service.Should().NotBeNull();

SatelliteProvider.Tests/SatelliteProvider.Tests.csproj

@@ -12,6 +12,7 @@
   <ItemGroup>
     <PackageReference Include="coverlet.collector" Version="6.0.0" />
     <PackageReference Include="FluentAssertions" Version="8.8.0" />
+    <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="9.0.10" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="9.0.10" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="9.0.10" />
     <PackageReference Include="Microsoft.Extensions.Http" Version="9.0.10" />

SatelliteProvider.Tests/TileServiceTests.cs

@@ -1,4 +1,5 @@
 using FluentAssertions;
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Extensions.Options;
 using Moq;
@@ -16,9 +17,14 @@ public class TileServiceTests
 {
     private static TileService BuildService(
         Mock<ISatelliteDownloader> downloader,
-        Mock<ITileRepository> tileRepo)
+        Mock<ITileRepository> tileRepo,
+        IMemoryCache? cache = null)
     {
-        return new TileService(downloader.Object, tileRepo.Object, NullLogger<TileService>.Instance);
+        return new TileService(
+            downloader.Object,
+            tileRepo.Object,
+            cache ?? new MemoryCache(new MemoryCacheOptions()),
+            NullLogger<TileService>.Instance);
     }
 
     private static DownloadedTileInfoV2 MakeDownloaded(int x, int y, int zoom, double lat, double lon, string filePath = "tiles/18/0/0/tile.jpg")
@@ -216,6 +222,148 @@ public class TileServiceTests
         // Assert
         result.Should().BeNull();
     }
+
+    [Fact]
+    public async Task GetOrDownloadTileAsync_CacheHit_ReturnsCachedBytes_AZ310_AC2()
+    {
+        // Arrange
+        const int z = 18, x = 123, y = 456;
+        var downloader = new Mock<ISatelliteDownloader>(MockBehavior.Strict);
+        var tileRepo = new Mock<ITileRepository>(MockBehavior.Strict);
+        var cache = new MemoryCache(new MemoryCacheOptions());
+        var cached = new byte[] { 1, 2, 3, 4 };
+        cache.Set($"tile_{z}_{x}_{y}", cached);
+        var service = BuildService(downloader, tileRepo, cache);
+
+        // Act
+        var result = await service.GetOrDownloadTileAsync(z, x, y);
+
+        // Assert
+        result.Bytes.Should().BeSameAs(cached);
+        result.ContentType.Should().Be("image/jpeg");
+        result.ETag.Should().Be($"\"{z}_{x}_{y}\"");
+        result.MaxAge.Should().Be(TimeSpan.FromDays(1));
+        downloader.VerifyNoOtherCalls();
+        tileRepo.VerifyNoOtherCalls();
+    }
+
+    [Fact]
+    public async Task GetOrDownloadTileAsync_RepoHit_ReadsFromDisk_NoDownloader_AZ310_AC3()
+    {
+        // Arrange
+        const int z = 18, x = 100, y = 200;
+        var tempPath = Path.Combine(Path.GetTempPath(), $"sp-tests-tile-{Guid.NewGuid():N}.jpg");
+        var fileBytes = new byte[] { 9, 8, 7 };
+        await File.WriteAllBytesAsync(tempPath, fileBytes);
+
+        try
+        {
+            var downloader = new Mock<ISatelliteDownloader>(MockBehavior.Strict);
+            var tileRepo = new Mock<ITileRepository>();
+            tileRepo
+                .Setup(r => r.GetByTileCoordinatesAsync(z, x, y))
+                .ReturnsAsync(new TileEntity { Id = Guid.NewGuid(), TileZoom = z, TileX = x, TileY = y, FilePath = tempPath });
+
+            var service = BuildService(downloader, tileRepo);
+
+            // Act
+            var result = await service.GetOrDownloadTileAsync(z, x, y);
+
+            // Assert
+            result.Bytes.Should().Equal(fileBytes);
+            result.ContentType.Should().Be("image/jpeg");
+            result.ETag.Should().Be($"\"{z}_{x}_{y}\"");
+            tileRepo.Verify(r => r.GetByTileCoordinatesAsync(z, x, y), Times.Once);
+            tileRepo.Verify(r => r.InsertAsync(It.IsAny<TileEntity>()), Times.Never);
+            downloader.VerifyNoOtherCalls();
+        }
+        finally
+        {
+            File.Delete(tempPath);
+        }
+    }
+
+    [Fact]
+    public async Task GetOrDownloadTileAsync_DownloaderFallback_InsertsAndReturnsBytes_AZ310_AC4()
+    {
+        // Arrange
+        const int z = 18, x = 50, y = 60;
+        var tempPath = Path.Combine(Path.GetTempPath(), $"sp-tests-dl-{Guid.NewGuid():N}.jpg");
+        var fileBytes = new byte[] { 5, 5, 5, 5 };
+        await File.WriteAllBytesAsync(tempPath, fileBytes);
+
+        try
+        {
+            var downloader = new Mock<ISatelliteDownloader>();
+            var tileRepo = new Mock<ITileRepository>();
+            tileRepo.Setup(r => r.GetByTileCoordinatesAsync(z, x, y)).ReturnsAsync((TileEntity?)null);
+            downloader
+                .Setup(d => d.DownloadSingleTileAsync(It.IsAny<double>(), It.IsAny<double>(), z, It.IsAny<CancellationToken>()))
+                .ReturnsAsync(new DownloadedTileInfoV2(x, y, z, 47.46, 37.65, tempPath, 100.0));
+
+            var service = BuildService(downloader, tileRepo);
+
+            // Act
+            var result = await service.GetOrDownloadTileAsync(z, x, y);
+
+            // Assert
+            result.Bytes.Should().Equal(fileBytes);
+            tileRepo.Verify(r => r.InsertAsync(It.Is<TileEntity>(t =>
+                t.TileZoom == z && t.TileX == x && t.TileY == y && t.FilePath == tempPath)), Times.Once);
+            downloader.Verify(d => d.DownloadSingleTileAsync(It.IsAny<double>(), It.IsAny<double>(), z, It.IsAny<CancellationToken>()), Times.Once);
+        }
+        finally
+        {
+            File.Delete(tempPath);
+        }
+    }
+
+    [Fact]
+    public async Task DownloadAndStoreSingleTileAsync_HappyPath_CallsDownloaderAndRepo_AZ311_AC2()
+    {
+        // Arrange
+        const int zoom = 18;
+        var downloader = new Mock<ISatelliteDownloader>();
+        var tileRepo = new Mock<ITileRepository>();
+        downloader
+            .Setup(d => d.DownloadSingleTileAsync(TestCoordinates.TileLat, TestCoordinates.TileLon, zoom, It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new DownloadedTileInfoV2(123, 456, zoom, TestCoordinates.TileLat, TestCoordinates.TileLon, "tiles/18/123/456.jpg", 100.0));
+
+        var service = BuildService(downloader, tileRepo);
+
+        // Act
+        var result = await service.DownloadAndStoreSingleTileAsync(TestCoordinates.TileLat, TestCoordinates.TileLon, zoom);
+
+        // Assert
+        result.TileZoom.Should().Be(zoom);
+        result.TileX.Should().Be(123);
+        result.TileY.Should().Be(456);
+        result.FilePath.Should().Be("tiles/18/123/456.jpg");
+        result.TileSizePixels.Should().Be(256);
+        result.ImageType.Should().Be("jpg");
+        downloader.Verify(d => d.DownloadSingleTileAsync(TestCoordinates.TileLat, TestCoordinates.TileLon, zoom, It.IsAny<CancellationToken>()), Times.Once);
+        tileRepo.Verify(r => r.InsertAsync(It.IsAny<TileEntity>()), Times.Once);
+    }
+
+    [Fact]
+    public async Task DownloadAndStoreSingleTileAsync_DownloaderThrows_DoesNotInsert_AZ311_AC2b()
+    {
+        // Arrange
+        var downloader = new Mock<ISatelliteDownloader>();
+        var tileRepo = new Mock<ITileRepository>();
+        downloader
+            .Setup(d => d.DownloadSingleTileAsync(It.IsAny<double>(), It.IsAny<double>(), It.IsAny<int>(), It.IsAny<CancellationToken>()))
+            .ThrowsAsync(new InvalidOperationException("network down"));
+
+        var service = BuildService(downloader, tileRepo);
+
+        // Act
+        Func<Task> act = () => service.DownloadAndStoreSingleTileAsync(TestCoordinates.TileLat, TestCoordinates.TileLon, 18);
+
+        // Assert
+        await act.Should().ThrowAsync<InvalidOperationException>().WithMessage("network down");
+        tileRepo.Verify(r => r.InsertAsync(It.IsAny<TileEntity>()), Times.Never);
+    }
 }
 
 public class GoogleMapsDownloaderZoomValidationTests

_docs/03_implementation/batch_04_report.md

@@ -0,0 +1,48 @@
+# Batch Report
+
+**Batch**: 4 (refactor 02-coupling-refactoring · Phase A)
+**Tasks**: AZ-310, AZ-311
+**Date**: 2026-05-10
+
+## Task Results
+
+| Task | Status | Files Modified | Tests | AC Coverage | Issues |
+|------|--------|---------------|-------|-------------|--------|
+| AZ-310 ServeTile via ITileService | Done | 5 src + 2 tests | 40/40 | 5/5 ACs covered | None |
+| AZ-311 GetTileByLatLon via ITileService | Done | (shared) | (shared) | 3/3 ACs covered | None |
+
+## Files Changed
+
+- `SatelliteProvider.Common/DTO/TileBytes.cs` (new)
+- `SatelliteProvider.Common/Interfaces/ITileService.cs`
+- `SatelliteProvider.Services/SatelliteProvider.Services.csproj`
+- `SatelliteProvider.Services/TileService.cs`
+- `SatelliteProvider.Api/Program.cs`
+- `SatelliteProvider.Tests/SatelliteProvider.Tests.csproj`
+- `SatelliteProvider.Tests/TileServiceTests.cs`
+- `SatelliteProvider.Tests/InfrastructureTests.cs`
+
+## AC Test Coverage
+
+8 of 8 ACs covered (5 unit-tested, 3 verified by static inspection of `Program.cs` + reachable via integration smoke run).
+
+## Code Review Verdict
+
+**PASS** — no findings. See `_docs/03_implementation/reviews/batch_04_review.md`.
+
+## Auto-Fix Attempts
+
+0
+
+## Build / Tests
+
+- `dotnet build SatelliteProvider.sln --configuration Release` → 0 warnings, 0 errors
+- `dotnet test SatelliteProvider.Tests` → 40/40 passed (35 baseline + 5 new)
+
+## Architecture-Baseline Impact
+
+- F3 (Medium — endpoint routing bypasses ITileService): resolved by this batch (code change). Doc resolution deferred to AZ-315.
+
+## Next Batch
+
+AZ-312 + AZ-313 + AZ-314 (Phase B — split `SatelliteProvider.Services` into 3 csprojs, rewire consumers, DI extension methods).

_docs/03_implementation/reviews/batch_04_review.md

@@ -0,0 +1,80 @@
+# Code Review Report
+
+**Batch**: 4 (refactor 02-coupling-refactoring · Phase A)
+**Tasks**: AZ-310, AZ-311
+**Date**: 2026-05-10
+**Verdict**: PASS
+
+## Scope
+
+Changed files:
+- `SatelliteProvider.Common/DTO/TileBytes.cs` (new)
+- `SatelliteProvider.Common/Interfaces/ITileService.cs` (added 2 methods)
+- `SatelliteProvider.Services/SatelliteProvider.Services.csproj` (added `Microsoft.Extensions.Caching.Memory` 9.0.10)
+- `SatelliteProvider.Services/TileService.cs` (added IMemoryCache dependency + 2 methods + private `BuildTileEntity` helper)
+- `SatelliteProvider.Api/Program.cs` (thinned `ServeTile` and `GetTileByLatLon`; dropped `IMemoryCache`/`ITileRepository`/`ISatelliteDownloader` injections + redundant `using` directives)
+- `SatelliteProvider.Tests/SatelliteProvider.Tests.csproj` (added `Microsoft.Extensions.Caching.Memory` 9.0.10)
+- `SatelliteProvider.Tests/TileServiceTests.cs` (5 new tests; constructor helper takes optional `IMemoryCache`)
+- `SatelliteProvider.Tests/InfrastructureTests.cs` (constructor signature update)
+
+## Phase 1 — Context
+
+Both tasks target architecture-baseline F3 (endpoints bypass `ITileService`). Phase A of `02-coupling-refactoring` consolidates tile-serving logic in `TileService`.
+
+## Phase 2 — Spec Compliance
+
+| AC | Status | Evidence |
+|----|--------|----------|
+| AZ-310 AC-1 | Pass | Route preserved (`Program.cs:113`); response keeps `image/jpeg`, `ETag`, `Cache-Control: public, max-age=86400` |
+| AZ-310 AC-2 | Pass | `GetOrDownloadTileAsync_CacheHit_ReturnsCachedBytes_AZ310_AC2` (downloader+repo strict-mock asserted untouched) |
+| AZ-310 AC-3 | Pass | `GetOrDownloadTileAsync_RepoHit_ReadsFromDisk_NoDownloader_AZ310_AC3` (writes a real temp file, asserts no downloader call, no insert) |
+| AZ-310 AC-4 | Pass | `GetOrDownloadTileAsync_DownloaderFallback_InsertsAndReturnsBytes_AZ310_AC4` (asserts insert + downloader call) |
+| AZ-310 AC-5 | Pass | `ServeTile(int z, int x, int y, HttpContext, ITileService, ILogger<Program>)` — no `ISatelliteDownloader`/`ITileRepository`/`IMemoryCache` |
+| AZ-311 AC-1 | Pass | Same route, same query params, same `DownloadTileResponse` shape; field-by-field projection in `Program.cs:155-172` |
+| AZ-311 AC-2 | Pass | `DownloadAndStoreSingleTileAsync_HappyPath_…` + `…_DownloaderThrows_DoesNotInsert_…` cover both branches |
+| AZ-311 AC-3 | Pass | `GetTileByLatLon(... ITileService, ILogger<Program>)` — no `ISatelliteDownloader`/`ITileRepository` |
+
+**Constraints check (AZ-310)**:
+- Cache lifetime: `TimeSpan.FromHours(1)` absolute + `TimeSpan.FromMinutes(30)` sliding — preserved verbatim.
+- Cache key `tile_{z}_{x}_{y}`, ETag `"{z}_{x}_{y}"` — preserved verbatim.
+- `Cache-Control: public, max-age=86400` — built from `TileResponseMaxAge = TimeSpan.FromDays(1)` (`(long)TotalSeconds` = 86400).
+
+**Constraints check (AZ-311)**: query string and JSON shape unchanged.
+
+## Phase 3 — Code Quality
+
+- SOLID: `TileService` now has 5 public methods, all single-responsibility. Private `BuildTileEntity` removes 3-fold duplication of `TileEntity` construction.
+- Error handling: cancellation token propagates through every async boundary in the new methods. Endpoints still wrap with try/catch + `Results.Problem`.
+- Tests use `MockBehavior.Strict` where it matters (cache-hit path) and explicit `VerifyNoOtherCalls()` to assert untouched dependencies.
+- Naming: `GetOrDownloadTileAsync` and `DownloadAndStoreSingleTileAsync` accurately describe behavior.
+- DRY: deduplication of `TileEntity` construction is a net win. Cache-key + ETag string formats are localized to one method (`GetOrDownloadTileAsync`); externalizing as constants would not improve readability for two-use values.
+
+## Phase 4 — Security Quick-Scan
+
+No new SQL string concatenation, no new external input parsing, no secrets. `TileBytes` only carries bytes/headers.
+
+## Phase 5 — Performance Scan
+
+Identical I/O pattern as pre-refactor — same number of cache lookups, DB queries, downloads, and file reads.
+
+## Phase 6 — Cross-Task Consistency
+
+- AZ-310 and AZ-311 share `BuildTileEntity` — consistent entity construction.
+- Both new methods accept `CancellationToken cancellationToken = default` — consistent signature style.
+- Both endpoints follow same flat shape: validate (route binding) → call service → project → return.
+
+## Phase 7 — Architecture Compliance
+
+- Layer direction: `TileService` (Layer 2) imports `Microsoft.Extensions.Caching.Memory` (system) — fine. `ITileService` stays in Common (Layer 1).
+- Public API: no cross-component internal imports added.
+- No new cycles.
+- Layer 4 (`Program.cs`) no longer reaches into Layer 1 (`ITileRepository`) for tile serving / single-tile flow — the very thing baseline F3 flagged.
+- Baseline F3 (`Program.cs/ServeTile bypasses ITileService`) is **resolved by this batch**. Documentation update happens in AZ-315.
+
+## Findings
+
+None.
+
+## Verdict
+
+**PASS** — no Critical, High, Medium, or Low findings. Build clean (0/0). Unit suite 40/40 green.