Kavita/API/Services/Tasks/CleanupService.cs

using System;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using API.Data;
using API.Entities.Enums;
using API.SignalR;
using Hangfire;
using Microsoft.AspNetCore.SignalR;
using Microsoft.Extensions.Logging;

namespace API.Services.Tasks;

public interface ICleanupService
{
    Task Cleanup();
    Task CleanupDbEntries();
    void CleanupCacheDirectory();
    Task DeleteSeriesCoverImages();
    Task DeleteChapterCoverImages();
    Task DeleteTagCoverImages();
    Task CleanupBackups();
    void CleanupTemp();
}
/// <summary>
/// Cleans up after operations on reoccurring basis
/// </summary>
public class CleanupService : ICleanupService
{
    private readonly ILogger<CleanupService> _logger;
    private readonly IUnitOfWork _unitOfWork;
    private readonly IEventHub _eventHub;
    private readonly IDirectoryService _directoryService;

    public CleanupService(ILogger<CleanupService> logger,
        IUnitOfWork unitOfWork, IEventHub eventHub,
        IDirectoryService directoryService)
    {
        _logger = logger;
        _unitOfWork = unitOfWork;
        _eventHub = eventHub;
        _directoryService = directoryService;
    }


    /// <summary>
    /// Cleans up Temp, cache, deleted cover images,  and old database backups
    /// </summary>
    [AutomaticRetry(Attempts = 3, LogEvents = false, OnAttemptsExceeded = AttemptsExceededAction.Fail)]
    public async Task Cleanup()
    {
        _logger.LogInformation("Starting Cleanup");
        await SendProgress(0F, "Starting cleanup");
        _logger.LogInformation("Cleaning temp directory");
        _directoryService.ClearDirectory(_directoryService.TempDirectory);
        await SendProgress(0.1F, "Cleaning temp directory");
        CleanupCacheDirectory();
        await SendProgress(0.25F, "Cleaning old database backups");
        _logger.LogInformation("Cleaning old database backups");
        await CleanupBackups();
        await SendProgress(0.50F, "Cleaning deleted cover images");
        _logger.LogInformation("Cleaning deleted cover images");
        await DeleteSeriesCoverImages();
        await SendProgress(0.6F, "Cleaning deleted cover images");
        await DeleteChapterCoverImages();
        await SendProgress(0.7F, "Cleaning deleted cover images");
        await DeleteTagCoverImages();
        await DeleteReadingListCoverImages();
        await SendProgress(1F, "Cleanup finished");
        _logger.LogInformation("Cleanup finished");
    }

    /// <summary>
    /// Cleans up abandon rows in the DB
    /// </summary>
    public async Task CleanupDbEntries()
    {
        await _unitOfWork.AppUserProgressRepository.CleanupAbandonedChapters();
        await _unitOfWork.PersonRepository.RemoveAllPeopleNoLongerAssociated();
        await _unitOfWork.GenreRepository.RemoveAllGenreNoLongerAssociated();
        await _unitOfWork.CollectionTagRepository.RemoveTagsWithoutSeries();
    }

    private async Task SendProgress(float progress, string subtitle)
    {
        await _eventHub.SendMessageAsync(MessageFactory.NotificationProgress,
            MessageFactory.CleanupProgressEvent(progress, subtitle));
    }

    /// <summary>
    /// Removes all series images that are not in the database. They must follow <see cref="ImageService.SeriesCoverImageRegex"/> filename pattern.
    /// </summary>
    public async Task DeleteSeriesCoverImages()
    {
        var images = await _unitOfWork.SeriesRepository.GetAllCoverImagesAsync();
        var files = _directoryService.GetFiles(_directoryService.CoverImageDirectory, ImageService.SeriesCoverImageRegex);
        _directoryService.DeleteFiles(files.Where(file => !images.Contains(_directoryService.FileSystem.Path.GetFileName(file))));
    }

    /// <summary>
    /// Removes all chapter/volume images that are not in the database. They must follow <see cref="ImageService.ChapterCoverImageRegex"/> filename pattern.
    /// </summary>
    public async Task DeleteChapterCoverImages()
    {
        var images = await _unitOfWork.ChapterRepository.GetAllCoverImagesAsync();
        var files = _directoryService.GetFiles(_directoryService.CoverImageDirectory, ImageService.ChapterCoverImageRegex);
        _directoryService.DeleteFiles(files.Where(file => !images.Contains(_directoryService.FileSystem.Path.GetFileName(file))));
    }

    /// <summary>
    /// Removes all collection tag images that are not in the database. They must follow <see cref="ImageService.CollectionTagCoverImageRegex"/> filename pattern.
    /// </summary>
    public async Task DeleteTagCoverImages()
    {
        var images = await _unitOfWork.CollectionTagRepository.GetAllCoverImagesAsync();
        var files = _directoryService.GetFiles(_directoryService.CoverImageDirectory, ImageService.CollectionTagCoverImageRegex);
        _directoryService.DeleteFiles(files.Where(file => !images.Contains(_directoryService.FileSystem.Path.GetFileName(file))));
    }

    /// <summary>
    /// Removes all reading list images that are not in the database. They must follow <see cref="ImageService.ReadingListCoverImageRegex"/> filename pattern.
    /// </summary>
    public async Task DeleteReadingListCoverImages()
    {
        var images = await _unitOfWork.ReadingListRepository.GetAllCoverImagesAsync();
        var files = _directoryService.GetFiles(_directoryService.CoverImageDirectory, ImageService.ReadingListCoverImageRegex);
        _directoryService.DeleteFiles(files.Where(file => !images.Contains(_directoryService.FileSystem.Path.GetFileName(file))));
    }

    /// <summary>
    /// Removes all files and directories in the cache and temp directory
    /// </summary>
    public void CleanupCacheDirectory()
    {
        _logger.LogInformation("Performing cleanup of Cache directory");
        _directoryService.ExistOrCreate(_directoryService.CacheDirectory);
        _directoryService.ExistOrCreate(_directoryService.TempDirectory);

        try
        {
            _directoryService.ClearDirectory(_directoryService.CacheDirectory);
            _directoryService.ClearDirectory(_directoryService.TempDirectory);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "There was an issue deleting one or more folders/files during cleanup");
        }

        _logger.LogInformation("Cache directory purged");
    }

    /// <summary>
    /// Removes Database backups older than configured total backups. If all backups are older than total backups days, only the latest is kept.
    /// </summary>
    public async Task CleanupBackups()
    {
        var dayThreshold = (await _unitOfWork.SettingsRepository.GetSettingsDtoAsync()).TotalBackups;
        _logger.LogInformation("Beginning cleanup of Database backups at {Time}", DateTime.Now);
        var backupDirectory =
            (await _unitOfWork.SettingsRepository.GetSettingAsync(ServerSettingKey.BackupDirectory)).Value;
        if (!_directoryService.Exists(backupDirectory)) return;

        var deltaTime = DateTime.Today.Subtract(TimeSpan.FromDays(dayThreshold));
        var allBackups = _directoryService.GetFiles(backupDirectory).ToList();
        var expiredBackups = allBackups.Select(filename => _directoryService.FileSystem.FileInfo.FromFileName(filename))
            .Where(f => f.CreationTime < deltaTime)
            .ToList();

        if (expiredBackups.Count == allBackups.Count)
        {
            _logger.LogInformation("All expired backups are older than {Threshold} days. Removing all but last backup", dayThreshold);
            var toDelete = expiredBackups.OrderByDescending(f => f.CreationTime).ToList();
            _directoryService.DeleteFiles(toDelete.Take(toDelete.Count - 1).Select(f => f.FullName));
        }
        else
        {
            _directoryService.DeleteFiles(expiredBackups.Select(f => f.FullName));
        }
        _logger.LogInformation("Finished cleanup of Database backups at {Time}", DateTime.Now);
    }

    public void CleanupTemp()
    {
        _logger.LogInformation("Performing cleanup of Temp directory");
        _directoryService.ExistOrCreate(_directoryService.TempDirectory);

        try
        {
            _directoryService.ClearDirectory(_directoryService.TempDirectory);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "There was an issue deleting one or more folders/files during cleanup");
        }

        _logger.LogInformation("Temp directory purged");
    }
}