Cleanup of lazy loading code. Made some DTOs use init rather than set to keep it clean.

API/Controllers/ImageController.cs

@@ -2,6 +2,7 @@
 using System.Linq;
 using System.Threading.Tasks;
 using API.DTOs;
+using API.Extensions;
 using API.Interfaces;
 using API.Interfaces.Services;
 using Microsoft.AspNetCore.Mvc;
@@ -28,51 +29,33 @@ namespace API.Controllers
         [HttpGet("chapter-cover")]
         public async Task<ActionResult> GetChapterCoverImage(int chapterId)
         {
-            // TODO: Write custom methods to just get the byte[] as fast as possible
+            var content = await _unitOfWork.VolumeRepository.GetChapterCoverImageAsync(chapterId);
-            var chapter = await _unitOfWork.VolumeRepository.GetChapterAsync(chapterId);
+            if (content == null) return BadRequest("No cover image");
-            var content = chapter.CoverImage;
+            const string format = "jpeg";
-            var format = "jpeg"; //Path.GetExtension("jpeg").Replace(".", "");
-            
-            // Calculates SHA1 Hash for byte[]
-            using var sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider();
-            Response.Headers.Add("ETag", string.Concat(sha1.ComputeHash(content).Select(x => x.ToString("X2"))));
-            Response.Headers.Add("Cache-Control", "private");
 
+            Response.AddCacheHeader(content);
             return File(content, "image/" + format);
         }
 
         [HttpGet("volume-cover")]
         public async Task<ActionResult> GetVolumeCoverImage(int volumeId)
         {
-            var volume = await _unitOfWork.SeriesRepository.GetVolumeAsync(volumeId);
+            var content = await _unitOfWork.SeriesRepository.GetVolumeCoverImageAsync(volumeId);
-            var content = volume.CoverImage;
+            if (content == null) return BadRequest("No cover image");
-            var format = "jpeg"; //Path.GetExtension("jpeg").Replace(".", "");
+            const string format = "jpeg";
-            
-            // Calculates SHA1 Hash for byte[]
-            using var sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider();
-            Response.Headers.Add("ETag", string.Concat(sha1.ComputeHash(content).Select(x => x.ToString("X2"))));
-            Response.Headers.Add("Cache-Control", "private");
 
+            Response.AddCacheHeader(content);
             return File(content, "image/" + format);
         }
         
         [HttpGet("series-cover")]
         public async Task<ActionResult> GetSeriesCoverImage(int seriesId)
         {
-            var series = await _unitOfWork.SeriesRepository.GetSeriesByIdAsync(seriesId);
+            var content = await _unitOfWork.SeriesRepository.GetSeriesCoverImageAsync(seriesId);
-            var content = series.CoverImage;
+            if (content == null) return BadRequest("No cover image");
-            var format = "jpeg"; //Path.GetExtension("jpeg").Replace(".", "");
+            const string format = "jpeg";
-
-            if (content.Length == 0)
-            {
-                // How do I handle? 
-            }
-            
-            // Calculates SHA1 Hash for byte[]
-            using var sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider();
-            Response.Headers.Add("ETag", string.Concat(sha1.ComputeHash(content).Select(x => x.ToString("X2"))));
-            Response.Headers.Add("Cache-Control", "private");
 
+            Response.AddCacheHeader(content);
             return File(content, "image/" + format);
         }
     }

API/DTOs/ChapterDto.cs

@@ -4,28 +4,27 @@ namespace API.DTOs
 {
     public class ChapterDto
     {
-        public int Id { get; set; }
+        public int Id { get; init; }
         /// <summary>
         /// Range of chapters. Chapter 2-4 -> "2-4". Chapter 2 -> "2".
         /// </summary>
-        public string Range { get; set; }
+        public string Range { get; init; }
         /// <summary>
         /// Smallest number of the Range. 
         /// </summary>
-        public string Number { get; set; }
+        public string Number { get; init; }
-        //public byte[] CoverImage { get; set; }
         /// <summary>
         /// Total number of pages in all MangaFiles
         /// </summary>
-        public int Pages { get; set; }
+        public int Pages { get; init; }
         /// <summary>
         /// The files that represent this Chapter
         /// </summary>
-        public ICollection<MangaFileDto> Files { get; set; }
+        public ICollection<MangaFileDto> Files { get; init; }
         /// <summary>
         /// Calculated at API time. Number of pages read for this Chapter for logged in user.
         /// </summary>
         public int PagesRead { get; set; }
-        public int VolumeId { get; set; }
+        public int VolumeId { get; init; }
     }
 }

API/DTOs/CreateLibraryDto.cs

@@ -7,11 +7,11 @@ namespace API.DTOs
     public class CreateLibraryDto
     {
         [Required]
-        public string Name { get; set; }
+        public string Name { get; init; }
         [Required]
-        public LibraryType Type { get; set; }
+        public LibraryType Type { get; init; }
         [Required]
         [MinLength(1)]
-        public IEnumerable<string> Folders { get; set; }
+        public IEnumerable<string> Folders { get; init; }
     }
 }

API/DTOs/ImageDto.cs

@@ -2,14 +2,14 @@
 {
     public class ImageDto
     {
-        public int Page { get; set; }
+        public int Page { get; init; }
         public string Filename { get; init; }
         public string FullPath { get; init; }
         public int Width { get; init; }
         public int Height { get; init; }
         public string Format { get; init; }
         public byte[] Content { get; init; }
-        public string MangaFileName { get; set; }
+        public string MangaFileName { get; init; }
-        public bool NeedsSplitting { get; set; }
+        public bool NeedsSplitting { get; init; }
     }
 }

API/DTOs/LibraryDto.cs

@@ -6,9 +6,9 @@ namespace API.DTOs
     public class LibraryDto
     {
         public int Id { get; init; }
-        public string Name { get; set; }
+        public string Name { get; init; }
-        public string CoverImage { get; set; }
+        public string CoverImage { get; init; }
-        public LibraryType Type { get; set; }
+        public LibraryType Type { get; init; }
-        public ICollection<string> Folders { get; set; }
+        public ICollection<string> Folders { get; init; }
     }
 }

API/DTOs/LoginDto.cs

@@ -2,7 +2,7 @@
 {
     public class LoginDto
     {
-        public string Username { get; set; }
+        public string Username { get; init; }
-        public string Password { get; set; }
+        public string Password { get; init; }
     }
 }

API/DTOs/MangaFileDto.cs

@@ -4,9 +4,9 @@ namespace API.DTOs
 {
     public class MangaFileDto
     {
-        public string FilePath { get; set; }
+        public string FilePath { get; init; }
-        public int NumberOfPages { get; set; } // TODO: Refactor to Pages
+        public int NumberOfPages { get; init; }
-        public MangaFormat Format { get; set; }
+        public MangaFormat Format { get; init; }
         
     }
 }

API/DTOs/MarkReadDto.cs

@@ -2,6 +2,6 @@
 {
     public class MarkReadDto
     {
-        public int SeriesId { get; set; }
+        public int SeriesId { get; init; }
     }
 }

API/DTOs/MemberDto.cs

@@ -8,11 +8,11 @@ namespace API.DTOs
     /// </summary>
     public class MemberDto
     {
-        public int Id { get; set; }
+        public int Id { get; init; }
-        public string Username { get; set; }
+        public string Username { get; init; }
-        public DateTime Created { get; set; }
+        public DateTime Created { get; init; }
-        public DateTime LastActive { get; set; }
+        public DateTime LastActive { get; init; }
-        public IEnumerable<LibraryDto> Libraries { get; set; }
+        public IEnumerable<LibraryDto> Libraries { get; init; }
-        public IEnumerable<string> Roles { get; set; }
+        public IEnumerable<string> Roles { get; init; }
     }
 }

API/DTOs/RegisterDto.cs

@@ -5,10 +5,10 @@ namespace API.DTOs
     public class RegisterDto
     {
         [Required]
-        public string Username { get; set; }
+        public string Username { get; init; }
         [Required]
         [StringLength(16, MinimumLength = 4)]
-        public string Password { get; set; }
+        public string Password { get; init; }
-        public bool IsAdmin { get; set; }
+        public bool IsAdmin { get; init; }
     }
 }

API/DTOs/SearchResultDto.cs

@@ -6,8 +6,8 @@
         public string Name { get; init; }
         public string OriginalName { get; init; }
         public string SortName { get; init; }
-        public byte[] CoverImage { get; init; } // This should be optional or a thumbImage (much smaller)
+        public byte[] CoverImage { get; init; } // This should be optional or a thumbImage (much smaller) // TODO: Refactor to lazy loading
-        
+        public string CoverImageUrl { get; init; }
         
         // Grouping information
         public string LibraryName { get; set; }

API/DTOs/SeriesDto.cs

@@ -8,7 +8,6 @@
         public string LocalizedName { get; init; }
         public string SortName { get; init; }
         public string Summary { get; init; }
-        public byte[] CoverImage { get; init; }
         public int Pages { get; init; }
         /// <summary>
         /// Sum of pages read from linked Volumes. Calculated at API-time.

API/DTOs/VolumeDto.cs

@@ -9,7 +9,6 @@ namespace API.DTOs
         public int Id { get; set; }
         public int Number { get; set; }
         public string Name { get; set; }
-        //public byte[] CoverImage { get; set; }
         public int Pages { get; set; }
         public int PagesRead { get; set; }
         public DateTime LastModified { get; set; }

API/Data/SeriesRepository.cs

@@ -244,6 +244,25 @@ namespace API.Data
                 s.UserReview = rating.Review;
             }
         }
+
+        public async Task<byte[]> GetVolumeCoverImageAsync(int volumeId)
+        {
+            return await _context.Volume
+                .Where(v => v.Id == volumeId)
+                .Select(v => v.CoverImage)
+                .AsNoTracking()
+                .SingleOrDefaultAsync();
+        }
+
+        public async Task<byte[]> GetSeriesCoverImageAsync(int seriesId)
+        {
+            return await _context.Series
+                .Where(s => s.Id == seriesId)
+                .Select(s => s.CoverImage)
+                .AsNoTracking()
+                .SingleOrDefaultAsync();
+        }
+
         private async Task AddVolumeModifiers(int userId, List<VolumeDto> volumes)
         {
             var userProgress = await _context.AppUserProgresses

API/Data/VolumeRepository.cs

@@ -50,7 +50,21 @@ namespace API.Data
                 .Where(c => c.VolumeId == volumeId)
                 .ToListAsync();
         }
-        
+
+        /// <summary>
+        /// Returns the cover image for a chapter id.
+        /// </summary>
+        /// <param name="chapterId"></param>
+        /// <returns></returns>
+        public async Task<byte[]> GetChapterCoverImageAsync(int chapterId)
+        {
+            return await _context.Chapter
+                .Where(c => c.Id == chapterId)
+                .Select(c => c.CoverImage)
+                .AsNoTracking()
+                .SingleOrDefaultAsync();
+        }
+
 
         public async Task<ChapterDto> GetChapterDtoAsync(int chapterId)
         {

API/Extensions/HttpExtensions.cs

@@ -1,4 +1,5 @@
-using System.Text.Json;
+using System.Linq;
+using System.Text.Json;
 using API.Helpers;
 using Microsoft.AspNetCore.Http;
 
@@ -18,6 +19,23 @@ namespace API.Extensions
             response.Headers.Add("Pagination", JsonSerializer.Serialize(paginationHeader, options));
             response.Headers.Add("Access-Control-Expose-Headers", "Pagination");
         }
+
+        /// <summary>
+        /// Calculates SHA1 hash for a byte[] and sets as ETag. Ensures Cache-Control: private header is added.
+        /// </summary>
+        /// <param name="response"></param>
+        /// <param name="content"></param>
+        public static void AddCacheHeader(this HttpResponse response, byte[] content)
+        {
+            // Calculates SHA1 Hash for byte[]
+            if (content != null && content.Length > 0)
+            {
+                using var sha1 = new System.Security.Cryptography.SHA1CryptoServiceProvider();
+                response.Headers.Add("ETag", string.Concat(sha1.ComputeHash(content).Select(x => x.ToString("X2"))));
+            }
+            
+            response.Headers.Add("Cache-Control", "private");
+        }
         
     }
 }

API/Interfaces/ISeriesRepository.cs

@@ -52,5 +52,8 @@ namespace API.Interfaces
         /// <param name="series"></param>
         /// <returns></returns>
         Task AddSeriesModifiers(int userId, List<SeriesDto> series);
+
+        Task<byte[]> GetVolumeCoverImageAsync(int volumeId);
+        Task<byte[]> GetSeriesCoverImageAsync(int seriesId);
     }
 }

API/Interfaces/IVolumeRepository.cs

@@ -12,5 +12,6 @@ namespace API.Interfaces
         Task<ChapterDto> GetChapterDtoAsync(int chapterId);
         Task<IList<MangaFile>> GetFilesForChapter(int chapterId);
         Task<IList<Chapter>> GetChaptersAsync(int volumeId);
+        Task<byte[]> GetChapterCoverImageAsync(int chapterId);
     }
 }