Add zip download feature for selected media objects

src/SF.PhotoPixels.API/Endpoints/PhotosEndpoints/DownloadObjects.cs

@@ -0,0 +1,33 @@
+using Ardalis.ApiEndpoints;
+using Mediator;
+using Microsoft.AspNetCore.Mvc;
+using SF.PhotoPixels.Application.Query.PhotoStorage.LoadMedia;
+using Swashbuckle.AspNetCore.Annotations;
+
+namespace SF.PhotoPixels.API.Endpoints.PhotosEndpoints;
+
+public class DownloadObjects : EndpointBaseAsync.WithRequest<DownloadObjectsRequest>.WithoutResult
+{
+    private readonly IMediator _mediator;
+
+    public DownloadObjects(IMediator mediator)
+    {
+        _mediator = mediator;
+    }
+
+    [HttpPost("/object/downloadZip")]
+    [SwaggerOperation(
+            Summary = "Download selected photos/videos as a zip file",
+            Description = "Download photos/videos from the server as a zip file",
+            Tags = new[] { "Object operations" }),
+    ]
+    public override async Task<ActionResult> HandleAsync([FromBody] DownloadObjectsRequest request, CancellationToken cancellationToken = default)
+    {
+        var result = await _mediator.Send(request, cancellationToken);
+
+        return result.Match<ActionResult>(
+            zip => File(zip, "application/zip", "files.zip"),
+            notFound => new NoContentResult()
+        );
+    }
+}

src/SF.PhotoPixels.Application/Query/PhotoStorage/LoadMedia/DownloadObjectsHandler.cs

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+using System.IO.Compression;
+using Marten;
+using Mediator;
+using OneOf;
+using OneOf.Types;
+using SF.PhotoPixels.Application.Core;
+using SF.PhotoPixels.Domain.Entities;
+using SF.PhotoPixels.Infrastructure.Storage;
+
+namespace SF.PhotoPixels.Application.Query.PhotoStorage.LoadMedia;
+
+public class DownloadObjectsHandler : IRequestHandler<DownloadObjectsRequest, OneOf<byte[], NotFound>>
+{
+    private readonly IExecutionContextAccessor _executionContextAccessor;
+    private readonly IDocumentSession _session;
+    private readonly IObjectStorage _objectStorage;
+
+    public DownloadObjectsHandler(IExecutionContextAccessor executionContextAccessor, IDocumentSession session, IObjectStorage objectStorage)
+    {
+        _executionContextAccessor = executionContextAccessor;
+        _session = session;
+        _objectStorage = objectStorage;
+    }
+
+    public async ValueTask<OneOf<byte[], NotFound>> Handle(DownloadObjectsRequest request, CancellationToken cancellationToken)
+    {
+        var objects = await _session.Query<ObjectProperties>()
+            .Where(obj => request.ObjectIds.Contains(obj.Id) && _executionContextAccessor.UserId == obj.UserId)
+            .Select(x => new { x.Hash, x.Extension, x.Name })
+            .ToListAsync(cancellationToken);
+
+        if (objects.Count == 0)
+            return new NotFound();
+
+        var userFolders = _objectStorage.GetUserFolders(_executionContextAccessor.UserId);
+
+        using var memoryStream = new MemoryStream();
+        using (var zipArchive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
+        {
+            foreach (var obj in objects)
+            {
+                var filePath = Path.Combine(userFolders.ObjectFolder, $"{obj.Hash}.{obj.Extension}");
+                var entry = zipArchive.CreateEntry(obj.Name, CompressionLevel.Optimal);
+
+                await using var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read, 4096, useAsync: true);
+                await using var entryStream = entry.Open();
+                await fileStream.CopyToAsync(entryStream, cancellationToken);
+            }
+        }
+
+        memoryStream.Position = 0;
+        return memoryStream.ToArray();
+    }
+}

src/SF.PhotoPixels.Application/Query/PhotoStorage/LoadMedia/DownloadObjectsRequest.cs

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+using System.ComponentModel.DataAnnotations;
+using Mediator;
+using OneOf;
+using OneOf.Types;
+
+namespace SF.PhotoPixels.Application.Query.PhotoStorage.LoadMedia;
+
+public class DownloadObjectsRequest : IRequest<OneOf<byte[], NotFound>>
+{
+    [Required]
+    public required List<string> ObjectIds { get; set; }
+}
+