feat(back): Timeline service add post modified since.

1 files changed, 56 insertions, 21 deletions

diff --git a/Timeline/Services/TimelineService.cs b/Timeline/Services/TimelineService.cs
index 6c1e91c6..e0b1b51d 100644
--- a/Timeline/Services/TimelineService.cs
+++ b/Timeline/Services/TimelineService.cs
@@ -106,6 +106,20 @@ namespace Timeline.Services
         Task<List<TimelinePost>> GetPosts(string timelineName);

 

         /// <summary>

+        /// Get the posts that have been modified since a given time 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>

+        /// <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);

+

+        /// <summary>

         /// Get the etag of data of a post.

         /// </summary>

         /// <param name="timelineName">The name of the timeline of the post.</param>

@@ -383,6 +397,34 @@ namespace Timeline.Services
             };

         }

 

+        private async Task<TimelinePost> MapTimelinePostFromEntity(TimelinePostEntity entity, string timelineName)

+        {

+            if (entity.Content == null)

+            {

+                throw new ArgumentException(ExceptionPostDeleted, nameof(entity));

+            }

+

+            var author = await _userService.GetUserById(entity.AuthorId);

+

+            var type = entity.ContentType;

+

+            ITimelinePostContent 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

+                );

+        }

+

         private TimelineEntity CreateNewTimelineEntity(string? name, long ownerId)

         {

             var currentTime = _clock.GetCurrentTime();

@@ -488,30 +530,23 @@ namespace Timeline.Services
             var posts = new List<TimelinePost>();

             foreach (var entity in postEntities)

             {

-                if (entity.Content == null)

-                {

-                    throw new Exception();

-                }

-

-                var author = await _userService.GetUserById(entity.AuthorId);

+                posts.Add(await MapTimelinePostFromEntity(entity, timelineName));

+            }

+            return posts;

+        }

 

-                var type = entity.ContentType;

+        public async Task<List<TimelinePost>> GetPosts(string timelineName, DateTime modifiedSince)

+        {

+            if (timelineName == null)

+                throw new ArgumentNullException(nameof(timelineName));

 

-                ITimelinePostContent content = type switch

-                {

-                    TimelinePostContentTypes.Text => new TextTimelinePostContent(entity.Content),

-                    TimelinePostContentTypes.Image => new ImageTimelinePostContent(entity.Content),

-                    _ => throw new DatabaseCorruptedException(string.Format(CultureInfo.InvariantCulture, ExceptionDatabaseUnknownContentType, type))

-                };

+            var timelineId = await FindTimelineId(timelineName);

+            var postEntities = await _database.TimelinePosts.OrderBy(p => p.Time).Where(p => p.TimelineId == timelineId && p.Content != null && p.LastUpdated > modifiedSince).ToListAsync();

 

-                posts.Add(new TimelinePost(

-                    id: entity.LocalId,

-                    author: author,

-                    content: content,

-                    time: entity.Time,

-                    lastUpdated: entity.LastUpdated,

-                    timelineName: timelineName

-                ));

+            var posts = new List<TimelinePost>();

+            foreach (var entity in postEntities)

+            {

+                posts.Add(await MapTimelinePostFromEntity(entity, timelineName));

             }

             return posts;

         }