public async Task <ActionResult> Post(string name, [FromBody] RegionCreationInfo creationInfo)
{
// _logger.LogInformation("Image Base64: {0}", creationInfo.ImageBase64);
var region = new PostRegionEntity {
Title = name
};
if (!string.IsNullOrEmpty(creationInfo?.ImageBase64))
{
region.IconData = Convert.FromBase64String(creationInfo.ImageBase64);
}
try
{
_dataFacade.AddPostRegion(region);
await _dataFacade.CommitChanges();
}
catch (DataFacadeException)
{
// name 字段不合法
return(BadRequest());
}
catch (Exception ex)
{
_logger.LogError(ex, "向数据源添加板块时抛出异常：{0}：{1}", ex.GetType(), ex.Message);
throw;
}
return(Ok());
}
/// <summary>
/// 向数据源中添加帖子。
/// </summary>
/// <param name="dataFacade">数据源的外观。</param>
/// <param name="indexEntity">帖子索引实体对象。</param>
/// <param name="contentEntity">帖子内容对象。</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="dataFacade"/>为null
/// 或
/// <paramref name="indexEntity"/>为null
/// 或
/// <paramref name="contentEntity"/>为null
/// </exception>
/// <exception cref="DataFacadeException">数据源抛出了未经处理的异常</exception>
public static async Task <int> AddPost(this IDataFacade dataFacade,
PostEntity indexEntity, PostContentEntity contentEntity)
{
if (dataFacade == null)
{
throw new ArgumentNullException(nameof(dataFacade));
}
if (indexEntity == null)
{
throw new ArgumentNullException(nameof(indexEntity));
}
if (contentEntity == null)
{
throw new ArgumentNullException(nameof(contentEntity));
}
// 将内容实体对象插入到数据源中。
await dataFacade.AddPostContentEntity(contentEntity);
// 将帖子索引实体对象插入到数据源中。
dataFacade.AddPostIndexEntity(indexEntity);
await dataFacade.CommitChanges();
return(indexEntity.Id);
}
/// <summary>
/// 移除帖子图片。
/// </summary>
/// <param name="dataFacade"></param>
/// <param name="postId">帖子 ID。</param>
/// <param name="indexesToRemove">要移除的图片索引。</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="dataFacade"/>为null
/// 或
/// <paramref name="indexesToRemove"/>为null
/// </exception>
/// <exception cref="PostNotFoundException">指定的帖子不存在。</exception>
public static async Task RemovePostImages(this IDataFacade dataFacade,
int postId, IEnumerable <int> indexesToRemove)
{
if (dataFacade == null)
{
throw new ArgumentNullException(nameof(dataFacade));
}
if (indexesToRemove == null)
{
throw new ArgumentNullException(nameof(indexesToRemove));
}
// TODO: 在这里添加代码对 indexesToRemove 进行验证
var indexEntity = await dataFacade.Posts
.Where(e => e.Id == postId)
.FirstOrDefaultAsync();
if (indexEntity == null)
{
throw new PostNotFoundException();
}
var contentId = new ObjectId(indexEntity.ContentId);
var contentEntity = await dataFacade.FindPostContentEntity(contentId);
var indexesToRemoveConcrete = indexesToRemove.ToArray();
// 删除图片数据
var removeTasks = new List <Task>();
foreach (var imageIndex in indexesToRemoveConcrete.Where(i => i >= 0 && i < contentEntity.ImageIds.Length))
{
var imageId = contentEntity.ImageIds[imageIndex];
if (imageId == null)
{
continue;
}
removeTasks.Add(dataFacade.RemoveImage(imageId.Value));
}
await Task.WhenAll(removeTasks);
// 更新内容实体对象
var imageSetDict = indexesToRemoveConcrete.ToDictionary <int, int, ObjectId?>(i => i, i => null);
await dataFacade.UpdatePostContentImageIds(contentId, imageSetDict);
// 更新索引实体对象中的最后更新时间戳
indexEntity.UpdateTime = DateTime.Now;
await dataFacade.CommitChanges();
}
/// <summary>
/// 当给定的用户不存在时，向数据源添加用户。返回用户实体对象。
/// </summary>
/// <param name="dataFacade">数据源外观。</param>
/// <param name="wechatId">用户的微信 ID。</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="dataFacade"/> 为 null
/// 或
/// <paramref name="wechatId"/> 为 null
/// </exception>
public static async Task <UserEntity> AddOrFindUserByWechatId(this IDataFacade dataFacade, string wechatId)
{
if (dataFacade == null)
{
throw new ArgumentNullException(nameof(dataFacade));
}
if (wechatId == null)
{
throw new ArgumentNullException(nameof(wechatId));
}
var existingEntity = await dataFacade.Users
.Where(u => u.WechatId == wechatId)
.FirstOrDefaultAsync();
if (existingEntity != null)
{
// 用户已经存在于数据源中
return(existingEntity);
}
// 用户在数据源中未找到
var userEntity = new UserEntity
{
WechatId = wechatId
};
try
{
dataFacade.AddUser(userEntity);
await dataFacade.CommitChanges();
return(userEntity);
}
catch (DataFacadeException)
{
// 重做用户查询
existingEntity = await dataFacade.Users
.Where(u => u.WechatId == wechatId)
.FirstOrDefaultAsync();
if (existingEntity != null)
{
return(existingEntity);
}
// 重做用户查询仍然无法找到用户
throw;
}
}
/// <summary>
/// 向数据源添加评论索引实体对象及其对应的内容实体对象。
/// </summary>
/// <param name="dataFacade"></param>
/// <param name="indexEntity">要添加的索引实体对象。</param>
/// <param name="contentEntity">要添加的内容实体对象。</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="indexEntity"/>为null
/// 或
/// <paramref name="contentEntity"/>为null
/// </exception>
public static async Task AddPostComment(this IDataFacade dataFacade,
CommentEntity indexEntity, CommentContentEntity contentEntity)
{
if (indexEntity == null)
{
throw new ArgumentNullException(nameof(indexEntity));
}
if (contentEntity == null)
{
throw new ArgumentNullException(nameof(contentEntity));
}
dataFacade.AddCommentIndexEntity(indexEntity);
await dataFacade.CommitChanges();
await dataFacade.AddCommentContentEntity(contentEntity);
}
/// <summary>
/// 删除指定的帖子。
/// </summary>
/// <param name="dataFacade"></param>
/// <param name="postId">要删除的帖子 ID。</param>
/// <param name="permanent">是否永久性地删除帖子数据</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="dataFacade"/>为null
/// </exception>
/// <exception cref="DataFacadeException">当数据源抛出了未经处理的异常时抛出</exception>
public static async Task RemovePost(this IDataFacade dataFacade, int postId, bool permanent = false)
{
if (dataFacade == null)
{
throw new ArgumentNullException(nameof(dataFacade));
}
if (permanent)
{
throw new NotImplementedException();
}
var indexEntity = await dataFacade.Posts
.Where(e => e.Id == postId && e.IsRemoved == false)
.FirstOrDefaultAsync();
if (indexEntity == null)
{
throw new PostNotFoundException();
}
indexEntity.IsRemoved = true;
await dataFacade.CommitChanges();
}
/// <summary>
/// 向给定的帖子上传图片。
/// </summary>
/// <param name="dataFacade"></param>
/// <param name="postId">帖子 ID。</param>
/// <param name="images">图片 ID 及对应图片的数据流工厂。</param>
/// <returns></returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="images"/>为null
/// </exception>
/// <exception cref="PostNotFoundException">
/// 指定的帖子不存在
/// 或
/// 帖子存在但其删除标记为true
/// </exception>
public static async Task UpdatePostImages(this IDataFacade dataFacade,
int postId, IReadOnlyDictionary <int, Func <Stream> > images)
{
if (images == null)
{
throw new ArgumentNullException(nameof(images));
}
// TODO: 在这里添加代码对 images 执行验证
var indexEntity = await dataFacade.Posts
// 下面的语句中务必使用 e.IsRemoved == true 以正确引导 EF Core 建立查询
.Where(e => e.Id == postId && e.IsRemoved == false)
.FirstOrDefaultAsync();
if (indexEntity == null)
{
// 指定的帖子不存在
throw new PostNotFoundException();
}
var contentId = new ObjectId(indexEntity.ContentId);
var contentEntity = await dataFacade.FindPostContentEntity(contentId);
// 删除已有的、被覆盖的图片数据
var removeTasks = new List <Task>();
foreach (var imageIndex in images.Keys.Where(i => i >= 0 && i < contentEntity.ImageIds.Length))
{
var imageId = contentEntity.ImageIds[imageIndex];
if (imageId == null)
{
continue;
}
removeTasks.Add(dataFacade.RemoveImage(imageId.Value));
}
await Task.WhenAll(removeTasks);
// 将图片上传至数据源
var imageIds = new ConcurrentDictionary <int, ObjectId?>();
var uploadTasks = new List <Task>();
foreach (var(index, imageDataStreamFactory) in images)
{
var imageDataStream = imageDataStreamFactory();
uploadTasks.Add(dataFacade.UploadImage(imageDataStream)
.ContinueWith((t, i) =>
{
imageDataStream.Close();
imageIds.TryAdd((int)i, t.Result);
}, index));
}
await Task.WhenAll(uploadTasks);
// 更新内容实体对象
await dataFacade.UpdatePostContentImageIds(contentId, imageIds);
// 更新索引实体对象中的上次更新时间戳
indexEntity.UpdateTime = DateTime.Now;
await dataFacade.CommitChanges();
}