Download Support (#298)

* Implemented the ability to download files (series, volume, chapter)

* Added RBS checks to ensure user is either an admin or has download role

* Added the ability to change a users feature RBS. Changed the Role seed to use reflection

API/Controllers/DownloadController.cs

@@ -0,0 +1,96 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using API.Extensions;
+using API.Interfaces;
+using API.Interfaces.Services;
+using API.Services;
+using Kavita.Common;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace API.Controllers
+{
+    [Authorize(Policy = "RequireDownloadRole")]
+    public class DownloadController : BaseApiController
+    {
+        private readonly IUnitOfWork _unitOfWork;
+        private readonly IArchiveService _archiveService;
+
+        public DownloadController(IUnitOfWork unitOfWork, IArchiveService archiveService)
+        {
+            _unitOfWork = unitOfWork;
+            _archiveService = archiveService;
+        }
+
+        [HttpGet("volume-size")]
+        public async Task<ActionResult<long>> GetVolumeSize(int volumeId)
+        {
+            var files = await _unitOfWork.VolumeRepository.GetFilesForVolume(volumeId);
+            return Ok(DirectoryService.GetTotalSize(files.Select(c => c.FilePath)));
+        }
+        
+        [HttpGet("chapter-size")]
+        public async Task<ActionResult<long>> GetChapterSize(int chapterId)
+        {
+            var files = await _unitOfWork.VolumeRepository.GetFilesForChapter(chapterId);
+            return Ok(DirectoryService.GetTotalSize(files.Select(c => c.FilePath)));
+        }
+        
+        [HttpGet("series-size")]
+        public async Task<ActionResult<long>> GetSeriesSize(int seriesId)
+        {
+            var files = await _unitOfWork.SeriesRepository.GetFilesForSeries(seriesId);
+            return Ok(DirectoryService.GetTotalSize(files.Select(c => c.FilePath)));
+        }
+        
+        [HttpGet("volume")]
+        public async Task<ActionResult> DownloadVolume(int volumeId)
+        {
+            var files = await _unitOfWork.VolumeRepository.GetFilesForVolume(volumeId);
+            try
+            {
+                var (fileBytes, zipPath) = await _archiveService.CreateZipForDownload(files.Select(c => c.FilePath), 
+                    $"download_{User.GetUsername()}_v{volumeId}");
+                return File(fileBytes, "application/zip", Path.GetFileName(zipPath));  
+            }
+            catch (KavitaException ex)
+            {
+                return BadRequest(ex.Message);
+            }
+        }
+        
+        [HttpGet("chapter")]
+        public async Task<ActionResult> DownloadChapter(int chapterId)
+        {
+            var files = await _unitOfWork.VolumeRepository.GetFilesForChapter(chapterId);
+            try
+            {
+                var (fileBytes, zipPath) = await _archiveService.CreateZipForDownload(files.Select(c => c.FilePath), 
+                    $"download_{User.GetUsername()}_c{chapterId}");
+                return File(fileBytes, "application/zip", Path.GetFileName(zipPath));  
+            }
+            catch (KavitaException ex)
+            {
+                return BadRequest(ex.Message);
+            }
+        }
+
+        [HttpGet("series")]
+        public async Task<ActionResult> DownloadSeries(int seriesId)
+        {
+            var files = await _unitOfWork.SeriesRepository.GetFilesForSeries(seriesId);
+            try
+            {
+                var (fileBytes, zipPath) = await _archiveService.CreateZipForDownload(files.Select(c => c.FilePath), 
+                    $"download_{User.GetUsername()}_s{seriesId}");
+                return File(fileBytes, "application/zip", Path.GetFileName(zipPath));  
+            }
+            catch (KavitaException ex)
+            {
+                return BadRequest(ex.Message);
+            }
+        }
+    }
+}