diff options
Diffstat (limited to 'BackEnd/Timeline/Services/TimelinePostService.cs')
| -rw-r--r-- | BackEnd/Timeline/Services/TimelinePostService.cs | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/BackEnd/Timeline/Services/TimelinePostService.cs b/BackEnd/Timeline/Services/TimelinePostService.cs new file mode 100644 index 00000000..36fcdbca --- /dev/null +++ b/BackEnd/Timeline/Services/TimelinePostService.cs @@ -0,0 +1,493 @@ +using Microsoft.EntityFrameworkCore;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Threading.Tasks;
+using Timeline.Entities;
+using Timeline.Helpers;
+using Timeline.Models;
+using Timeline.Services.Exceptions;
+using SixLabors.ImageSharp;
+using static Timeline.Resources.Services.TimelineService;
+using Microsoft.Extensions.Logging;
+
+namespace Timeline.Services
+{
+ public class PostData : ICacheableData
+ {
+#pragma warning disable CA1819 // Properties should not return arrays
+ public byte[] Data { get; set; } = default!;
+#pragma warning restore CA1819 // Properties should not return arrays
+ public string Type { get; set; } = default!;
+ public string ETag { get; set; } = default!;
+ public DateTime? LastModified { get; set; } // TODO: Why nullable?
+ }
+
+ public interface ITimelinePostService
+ {
+ /// <summary>
+ /// Get all the posts in the timeline.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline.</param>
+ /// <param name="modifiedSince">The time that posts have been modified since.</param>
+ /// <param name="includeDeleted">Whether include deleted posts.</param>
+ /// <returns>A list of all posts.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ Task<List<TimelinePost>> GetPosts(string timelineName, DateTime? modifiedSince = null, bool includeDeleted = false);
+
+ /// <summary>
+ /// Get the etag of data of a post.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline of the post.</param>
+ /// <param name="postId">The id of the post.</param>
+ /// <returns>The etag of the data.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="TimelinePostNotExistException">Thrown when post of <paramref name="postId"/> does not exist or has been deleted.</exception>
+ /// <exception cref="TimelinePostNoDataException">Thrown when post has no data.</exception>
+ /// <seealso cref="GetPostData(string, long)"/>
+ Task<string> GetPostDataETag(string timelineName, long postId);
+
+ /// <summary>
+ /// Get the data of a post.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline of the post.</param>
+ /// <param name="postId">The id of the post.</param>
+ /// <returns>The etag of the data.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="TimelinePostNotExistException">Thrown when post of <paramref name="postId"/> does not exist or has been deleted.</exception>
+ /// <exception cref="TimelinePostNoDataException">Thrown when post has no data.</exception>
+ /// <seealso cref="GetPostDataETag(string, long)"/>
+ Task<PostData> GetPostData(string timelineName, long postId);
+
+ /// <summary>
+ /// Create a new text post in timeline.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline to create post against.</param>
+ /// <param name="authorId">The author's user id.</param>
+ /// <param name="text">The content text.</param>
+ /// <param name="time">The time of the post. If null, then current time is used.</param>
+ /// <returns>The info of the created post.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> or <paramref name="text"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="UserNotExistException">Thrown if user of <paramref name="authorId"/> does not exist.</exception>
+ Task<TimelinePost> CreateTextPost(string timelineName, long authorId, string text, DateTime? time);
+
+ /// <summary>
+ /// Create a new image post in timeline.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline to create post against.</param>
+ /// <param name="authorId">The author's user id.</param>
+ /// <param name="imageData">The image data.</param>
+ /// <param name="time">The time of the post. If null, then use current time.</param>
+ /// <returns>The info of the created post.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> or <paramref name="imageData"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="UserNotExistException">Thrown if user of <paramref name="authorId"/> does not exist.</exception>
+ /// <exception cref="ImageException">Thrown if data is not a image. Validated by <see cref="ImageValidator"/>.</exception>
+ Task<TimelinePost> CreateImagePost(string timelineName, long authorId, byte[] imageData, DateTime? time);
+
+ /// <summary>
+ /// Delete a post.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline to delete post against.</param>
+ /// <param name="postId">The id of the post to delete.</param>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="TimelinePostNotExistException">Thrown when the post with given id does not exist or is deleted already.</exception>
+ /// <remarks>
+ /// First use <see cref="HasPostModifyPermission(string, long, long, bool)"/> to check the permission.
+ /// </remarks>
+ Task DeletePost(string timelineName, long postId);
+
+ /// <summary>
+ /// Delete all posts of the given user. Used when delete a user.
+ /// </summary>
+ /// <param name="userId">The id of the user.</param>
+ Task DeleteAllPostsOfUser(long userId);
+
+ /// <summary>
+ /// Verify whether a user has the permission to modify a post.
+ /// </summary>
+ /// <param name="timelineName">The name of the timeline.</param>
+ /// <param name="postId">The id of the post.</param>
+ /// <param name="modifierId">The id of the user to check on.</param>
+ /// <param name="throwOnPostNotExist">True if you want it to throw <see cref="TimelinePostNotExistException"/>. Default false.</param>
+ /// <returns>True if can modify, false if can't modify.</returns>
+ /// <exception cref="ArgumentNullException">Thrown when <paramref name="timelineName"/> is null.</exception>
+ /// <exception cref="ArgumentException">Throw when <paramref name="timelineName"/> is of bad format.</exception>
+ /// <exception cref="TimelineNotExistException">
+ /// Thrown when timeline with name <paramref name="timelineName"/> does not exist.
+ /// If it is a personal timeline, then inner exception is <see cref="UserNotExistException"/>.
+ /// </exception>
+ /// <exception cref="TimelinePostNotExistException">Thrown when the post with given id does not exist or is deleted already and <paramref name="throwOnPostNotExist"/> is true.</exception>
+ /// <remarks>
+ /// Unless <paramref name="throwOnPostNotExist"/> is true, this method should return true if the post does not exist.
+ /// If the post is deleted, its author info still exists, so it is checked as the post is not deleted unless <paramref name="throwOnPostNotExist"/> is true.
+ /// This method does not check whether the user is administrator.
+ /// It only checks whether he is the author of the post or the owner of the timeline.
+ /// Return false when user with modifier id does not exist.
+ /// </remarks>
+ Task<bool> HasPostModifyPermission(string timelineName, long postId, long modifierId, bool throwOnPostNotExist = false);
+ }
+
+ public class TimelinePostService : ITimelinePostService
+ {
+ private readonly ILogger<TimelinePostService> _logger;
+ private readonly DatabaseContext _database;
+ private readonly IBasicTimelineService _basicTimelineService;
+ private readonly IUserService _userService;
+ private readonly IDataManager _dataManager;
+ private readonly IImageValidator _imageValidator;
+ private readonly IClock _clock;
+
+ public TimelinePostService(ILogger<TimelinePostService> logger, DatabaseContext database, IBasicTimelineService basicTimelineService, IUserService userService, IDataManager dataManager, IImageValidator imageValidator, IClock clock)
+ {
+ _logger = logger;
+ _database = database;
+ _basicTimelineService = basicTimelineService;
+ _userService = userService;
+ _dataManager = dataManager;
+ _imageValidator = imageValidator;
+ _clock = clock;
+ }
+
+ private async Task<TimelinePost> MapTimelinePostFromEntity(TimelinePostEntity entity, string timelineName)
+ {
+ User? author = entity.AuthorId.HasValue ? await _userService.GetUser(entity.AuthorId.Value) : null;
+
+ ITimelinePostContent? content = null;
+
+ if (entity.Content != null)
+ {
+ var type = entity.ContentType;
+
+ content = type switch
+ {
+ TimelinePostContentTypes.Text => new TextTimelinePostContent(entity.Content),
+ TimelinePostContentTypes.Image => new ImageTimelinePostContent(entity.Content),
+ _ => throw new DatabaseCorruptedException(string.Format(CultureInfo.InvariantCulture, ExceptionDatabaseUnknownContentType, type))
+ };
+ }
+
+ return new TimelinePost(
+ id: entity.LocalId,
+ author: author,
+ content: content,
+ time: entity.Time,
+ lastUpdated: entity.LastUpdated,
+ timelineName: timelineName
+ );
+ }
+
+ public async Task<List<TimelinePost>> GetPosts(string timelineName, DateTime? modifiedSince = null, bool includeDeleted = false)
+ {
+ modifiedSince = modifiedSince?.MyToUtc();
+
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+ IQueryable<TimelinePostEntity> query = _database.TimelinePosts.Where(p => p.TimelineId == timelineId);
+
+ if (!includeDeleted)
+ {
+ query = query.Where(p => p.Content != null);
+ }
+
+ if (modifiedSince.HasValue)
+ {
+ query = query.Include(p => p.Author).Where(p => p.LastUpdated >= modifiedSince || (p.Author != null && p.Author.UsernameChangeTime >= modifiedSince));
+ }
+
+ query = query.OrderBy(p => p.Time);
+
+ var postEntities = await query.ToListAsync();
+
+ var posts = new List<TimelinePost>();
+ foreach (var entity in postEntities)
+ {
+ posts.Add(await MapTimelinePostFromEntity(entity, timelineName));
+ }
+ return posts;
+ }
+
+ public async Task<string> GetPostDataETag(string timelineName, long postId)
+ {
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+
+ var postEntity = await _database.TimelinePosts.Where(p => p.TimelineId == timelineId && p.LocalId == postId).SingleOrDefaultAsync();
+
+ if (postEntity == null)
+ throw new TimelinePostNotExistException(timelineName, postId, false);
+
+ if (postEntity.Content == null)
+ throw new TimelinePostNotExistException(timelineName, postId, true);
+
+ if (postEntity.ContentType != TimelinePostContentTypes.Image)
+ throw new TimelinePostNoDataException(ExceptionGetDataNonImagePost);
+
+ var tag = postEntity.Content;
+
+ return tag;
+ }
+
+ public async Task<PostData> GetPostData(string timelineName, long postId)
+ {
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+ var postEntity = await _database.TimelinePosts.Where(p => p.TimelineId == timelineId && p.LocalId == postId).SingleOrDefaultAsync();
+
+ if (postEntity == null)
+ throw new TimelinePostNotExistException(timelineName, postId, false);
+
+ if (postEntity.Content == null)
+ throw new TimelinePostNotExistException(timelineName, postId, true);
+
+ if (postEntity.ContentType != TimelinePostContentTypes.Image)
+ throw new TimelinePostNoDataException(ExceptionGetDataNonImagePost);
+
+ var tag = postEntity.Content;
+
+ byte[] data;
+
+ try
+ {
+ data = await _dataManager.GetEntry(tag);
+ }
+ catch (InvalidOperationException e)
+ {
+ throw new DatabaseCorruptedException(ExceptionGetDataDataEntryNotExist, e);
+ }
+
+ if (postEntity.ExtraContent == null)
+ {
+ _logger.LogWarning(LogGetDataNoFormat);
+ var format = Image.DetectFormat(data);
+ postEntity.ExtraContent = format.DefaultMimeType;
+ await _database.SaveChangesAsync();
+ }
+
+ return new PostData
+ {
+ Data = data,
+ Type = postEntity.ExtraContent,
+ ETag = tag,
+ LastModified = postEntity.LastUpdated
+ };
+ }
+
+ public async Task<TimelinePost> CreateTextPost(string timelineName, long authorId, string text, DateTime? time)
+ {
+ time = time?.MyToUtc();
+
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+ if (text == null)
+ throw new ArgumentNullException(nameof(text));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+ var timelineEntity = await _database.Timelines.Where(t => t.Id == timelineId).SingleAsync();
+
+ var author = await _userService.GetUser(authorId);
+
+ var currentTime = _clock.GetCurrentTime();
+ var finalTime = time ?? currentTime;
+
+ timelineEntity.CurrentPostLocalId += 1;
+
+ var postEntity = new TimelinePostEntity
+ {
+ LocalId = timelineEntity.CurrentPostLocalId,
+ ContentType = TimelinePostContentTypes.Text,
+ Content = text,
+ AuthorId = authorId,
+ TimelineId = timelineId,
+ Time = finalTime,
+ LastUpdated = currentTime
+ };
+ _database.TimelinePosts.Add(postEntity);
+ await _database.SaveChangesAsync();
+
+
+ return new TimelinePost(
+ id: postEntity.LocalId,
+ content: new TextTimelinePostContent(text),
+ time: finalTime,
+ author: author,
+ lastUpdated: currentTime,
+ timelineName: timelineName
+ );
+ }
+
+ public async Task<TimelinePost> CreateImagePost(string timelineName, long authorId, byte[] data, DateTime? time)
+ {
+ time = time?.MyToUtc();
+
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+ if (data == null)
+ throw new ArgumentNullException(nameof(data));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+ var timelineEntity = await _database.Timelines.Where(t => t.Id == timelineId).SingleAsync();
+
+ var author = await _userService.GetUser(authorId);
+
+ var imageFormat = await _imageValidator.Validate(data);
+
+ var imageFormatText = imageFormat.DefaultMimeType;
+
+ var tag = await _dataManager.RetainEntry(data);
+
+ var currentTime = _clock.GetCurrentTime();
+ var finalTime = time ?? currentTime;
+
+ timelineEntity.CurrentPostLocalId += 1;
+
+ var postEntity = new TimelinePostEntity
+ {
+ LocalId = timelineEntity.CurrentPostLocalId,
+ ContentType = TimelinePostContentTypes.Image,
+ Content = tag,
+ ExtraContent = imageFormatText,
+ AuthorId = authorId,
+ TimelineId = timelineId,
+ Time = finalTime,
+ LastUpdated = currentTime
+ };
+ _database.TimelinePosts.Add(postEntity);
+ await _database.SaveChangesAsync();
+
+ return new TimelinePost(
+ id: postEntity.LocalId,
+ content: new ImageTimelinePostContent(tag),
+ time: finalTime,
+ author: author,
+ lastUpdated: currentTime,
+ timelineName: timelineName
+ );
+ }
+
+ public async Task DeletePost(string timelineName, long id)
+ {
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+
+ var post = await _database.TimelinePosts.Where(p => p.TimelineId == timelineId && p.LocalId == id).SingleOrDefaultAsync();
+
+ if (post == null)
+ throw new TimelinePostNotExistException(timelineName, id, false);
+
+ if (post.Content == null)
+ throw new TimelinePostNotExistException(timelineName, id, true);
+
+ string? dataTag = null;
+
+ if (post.ContentType == TimelinePostContentTypes.Image)
+ {
+ dataTag = post.Content;
+ }
+
+ post.Content = null;
+ post.LastUpdated = _clock.GetCurrentTime();
+
+ await _database.SaveChangesAsync();
+
+ if (dataTag != null)
+ {
+ await _dataManager.FreeEntry(dataTag);
+ }
+ }
+
+ public async Task DeleteAllPostsOfUser(long userId)
+ {
+ var posts = await _database.TimelinePosts.Where(p => p.AuthorId == userId).ToListAsync();
+
+ var now = _clock.GetCurrentTime();
+
+ var dataTags = new List<string>();
+
+ foreach (var post in posts)
+ {
+ if (post.Content != null)
+ {
+ if (post.ContentType == TimelinePostContentTypes.Image)
+ {
+ dataTags.Add(post.Content);
+ }
+ post.Content = null;
+ }
+ post.LastUpdated = now;
+ }
+
+ await _database.SaveChangesAsync();
+
+ foreach (var dataTag in dataTags)
+ {
+ await _dataManager.FreeEntry(dataTag);
+ }
+ }
+
+ public async Task<bool> HasPostModifyPermission(string timelineName, long postId, long modifierId, bool throwOnPostNotExist = false)
+ {
+ if (timelineName == null)
+ throw new ArgumentNullException(nameof(timelineName));
+
+ var timelineId = await _basicTimelineService.GetTimelineIdByName(timelineName);
+
+ var timelineEntity = await _database.Timelines.Where(t => t.Id == timelineId).Select(t => new { t.OwnerId }).SingleAsync();
+
+ var postEntity = await _database.TimelinePosts.Where(p => p.Id == postId).Select(p => new { p.Content, p.AuthorId }).SingleOrDefaultAsync();
+
+ if (postEntity == null)
+ {
+ if (throwOnPostNotExist)
+ throw new TimelinePostNotExistException(timelineName, postId, false);
+ else
+ return true;
+ }
+
+ if (postEntity.Content == null && throwOnPostNotExist)
+ {
+ throw new TimelinePostNotExistException(timelineName, postId, true);
+ }
+
+ return timelineEntity.OwnerId == modifierId || postEntity.AuthorId == modifierId;
+ }
+ }
+}
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