public void DeletePost(BlogContext context, string sessionToken, int postId)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var post = context.Posts.SingleOrDefault(p => p.PostId == postId);
if (post == null)
{
throw new NoSuchPostException();
}
if (post.UserId != user.UserId)
{
throw new NoPermissionsException();
}
var commentsToDelete = (from comment in context.Comments
where comment.PostId == postId
select comment).ToList();
foreach (var comment in commentsToDelete)
{
context.Comments.Remove(comment);
}
context.Posts.Remove(post);
context.SaveChanges();
}
public User GetUserBySessionToken(BlogContext context, string sessionToken)
{
var session = context.Sessions
.Include("User")
.SingleOrDefault(s => s.SessionToken == sessionToken);
if (session == null)
{
throw new InvalidSessionException();
}
return session.User;
}
public PostDTO GetPost(BlogContext context, string sessionToken, int postId)
{
_authenticationService.MakeSureSessionTokenIsOk(context, sessionToken);
var post = context.Posts
.Include("Comments")
.SingleOrDefault(p => p.PostId == postId);
if (post == null)
{
throw new NoSuchPostException();
}
return _postToPostDtoMapper.Map(post);
}
public PostDTO CreatePost(BlogContext context, string sessionToken, string postText)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var post = new Post
{
User = user,
Text = postText,
CreatedAt = DateTime.UtcNow,
ModifiedAt = null,
Comments = new List<Comment>()
};
post = context.Posts.Add(post);
context.SaveChanges();
return _postToPostDtoMapper.Map(post);
}
public Page<BriefPostDTO> GetPosts(BlogContext context, string sessionToken, int itemsPerPage, int page)
{
_authenticationService.MakeSureSessionTokenIsOk(context, sessionToken);
var postCount = context.Posts.Count();
var posts = context.Posts
.Include("User")
.Include("Comments")
.OrderBy(post => post.PostId)
.Skip(page * itemsPerPage)
.Take(itemsPerPage);
return new Page<BriefPostDTO>
{
TotalItemCount = postCount,
Items = _postToBriefPostDtoMapper.Map(posts)
};
}
public void DeleteComment(BlogContext context, string sessionToken, int commentId)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var comment = context.Comments.SingleOrDefault(c => c.CommentId == commentId);
if (comment == null)
{
throw new NoSuchCommentException();
}
if (comment.UserId != user.UserId)
{
throw new NoPermissionsException();
}
context.Comments.Remove(comment);
context.SaveChanges();
}
public UserDTO CreateUser(BlogContext context, string userName, string password)
{
var existingUser = context.Users.SingleOrDefault(u => u.UserName == userName);
if (existingUser != null)
{
throw new UserNameAlreadyRegisteredException();
}
var user = new User
{
UserName = userName,
Password = password,
CreatedAt = DateTime.UtcNow,
ModifiedAt = null
};
user = context.Users.Add(user);
context.SaveChanges();
return _userToUserDtoMapper.Map(user);
}
public UserDetailsDTO GetUserDetails(
BlogContext context,
string sessionToken,
int userId,
int maxNumberOfRecentPosts,
int maxNumberOfRecentComments)
{
_authenticationService.MakeSureSessionTokenIsOk(context, sessionToken);
var user = context.Users.SingleOrDefault(u => u.UserId == userId);
if (user == null)
{
throw new NoSuchUserException();
}
var numberOfPosts = context.Posts.Count(post => post.UserId == userId);
var recentPosts = context.Posts
.Include("Comments")
.Where(post => post.UserId == userId)
.OrderByDescending(post => post.PostId)
.Take(maxNumberOfRecentPosts)
.ToList();
var numberOfComments = context.Comments.Count(comment => comment.UserId == userId);
var recentComments = context.Comments
.Where(comment => comment.UserId == userId)
.OrderByDescending(comment => comment.CommentId)
.Take(maxNumberOfRecentComments)
.ToList();
return new UserDetailsDTO
{
UserId = user.UserId,
UserName = user.UserName,
RegisteredAt = user.CreatedAt,
NumberOfPosts = numberOfPosts,
RecentPosts = _postToBriefPostDtoMapper.Map(recentPosts),
NumberOfComments = numberOfComments,
RecentComments = _commentToCommentDtoMapper.Map(recentComments)
};
}
public CommentDTO UpdateComment(BlogContext context, string sessionToken, int commentId, string commentText)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var comment = context.Comments.SingleOrDefault(c => c.CommentId == commentId);
if (comment == null)
{
throw new NoSuchCommentException();
}
if (comment.UserId != user.UserId)
{
throw new NoPermissionsException();
}
comment.Text = commentText;
comment.ModifiedAt = DateTime.UtcNow;
context.SaveChanges();
return _commentToCommentDtoMapper.Map(comment);
}
public IList<ActiveUserDTO> GetMostActiveUsers(BlogContext context, string sessionToken, int maxNumberOfMostActiveUsers)
{
_authenticationService.MakeSureSessionTokenIsOk(context, sessionToken);
var activeUsers =
(from post in context.Posts
group post by new
{
post.UserId,
post.User.UserName
}
into g
let postCount = g.Count()
orderby postCount descending
select new ActiveUserDTO
{
UserId = g.Key.UserId,
UserName = g.Key.UserName,
NumberOfPosts = postCount
}).Take(maxNumberOfMostActiveUsers).ToList();
return activeUsers;
}
public PostDTO UpdatePost(BlogContext context, string sessionToken, int postId, string postText)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var post = context.Posts
.Include("Comments")
.SingleOrDefault(p => p.PostId == postId);
if (post == null)
{
throw new NoSuchPostException();
}
if (post.UserId != user.UserId)
{
throw new NoPermissionsException();
}
post.Text = postText;
post.ModifiedAt = DateTime.UtcNow;
context.SaveChanges();
return _postToPostDtoMapper.Map(post);
}
public SessionDTO Authenticate(BlogContext context, string userName, string password)
{
var user = context.Users.SingleOrDefault(u => u.UserName == userName);
if (user == null)
{
throw new NoSuchUserException();
}
if (user.Password != password)
{
throw new InvalidPasswordException();
}
var session = new Session
{
SessionToken = Guid.NewGuid().ToString(),
User = user
};
session = context.Sessions.Add(session);
context.SaveChanges();
return _sessionToSessionDtoMapper.Map(session);
}
public CommentDTO CreateComment(BlogContext context, string sessionToken, int postId, string commentText)
{
var user = _authenticationService.GetUserBySessionToken(context, sessionToken);
var post = context.Posts.SingleOrDefault(p => p.PostId == postId);
if (post == null)
{
throw new NoSuchPostException();
}
var comment = new Comment
{
Text = commentText,
CreatedAt = DateTime.UtcNow,
ModifiedAt = null,
Post = post,
User = user
};
context.Comments.Add(comment);
context.SaveChanges();
return _commentToCommentDtoMapper.Map(comment);
}
public void MakeSureSessionTokenIsOk(BlogContext context, string sessionToken)
{
GetUserBySessionToken(context, sessionToken);
}
