一些概念
在大叔框架里总觉得缺点什么，在最近的项目开发中，终于知道缺什么了，分布式文件存储组件，就是缺它，呵呵，对于分布式文件存储来说，业界比较公认的是FastDFS组件，它自己本身就是集群机制，有自己的路由选择和文件存储两个部分，我们通过FastDFS的客户端进行上传后，它会返回一个在FastDFS上存储的路径，这当然是IO路径，我们只要在服务器上开个Http服务器，就可以以Http的方法访问你的文件了。
我的组件实现方式
前端上传控件（表单方式，swf方式，js方法均可）将文件流传给我们的FastDFS客户端，通过客户端与服务端建立Socket连接，将数据包发给FastDFS服务端并等待返回，上传成功后返回路径，我们可以对路径进行ＨＴＴＰ的处理，并存入数据库
fastDFS配合nginx服务器自动生成指定尺寸的图像
原图像地址： http://www.fastdfs.com/demo/pictruename.jpg
指定尺寸的图像地址：http://www.fastdfs.com/demo/pictruename_100x100.jpg
技术实现
１ 一个接口，定义三种上传规格，普通文件，图像文件和视频文件（一般需要对它进行截力）
public interface IFileUploader { /// <summary> /// 上传视频文件 /// </summary> /// <param name="param"></param> /// <returns></returns> VideoUploadResult UploadVideo(VideoUploadParameter param); /// <summary> /// 上传普通文件 /// </summary> /// <param name="filePath"></param> /// <returns></returns> FileUploadResult UploadFile(FileUploadParameter param); /// <summary> /// 上传图片 /// </summary> /// <param name="param"></param> /// <returns></returns> /// <remarks>Update:cyr(Ben) 20150317</remarks> ImageUploadResult UploadImage(ImageUploadParameter param); }
２ 一批方法参数，包括了文件，图像和视频等
/// <summary> /// 文件上传参数基类 /// </summary> public abstract class UploadParameterBase { public UploadParameterBase() { MaxSize = 1024 * 1024 * 8; } /// <summary> /// 前一次上传时生成的服务器端文件名，如果需要断点续传，需传入此文件名 /// </summary> public string ServiceFileName { get; set; } /// <summary> /// 文件流 /// </summary> public Stream Stream { get; set; } /// <summary> /// 文件名 /// </summary> public string FileName { get; set; } /// <summary> /// 文件大小限制（单位bit 默认1M） /// </summary> public int MaxSize { get; protected set; } /// <summary> /// 上传文件类型限制 /// </summary> public string[] FilenameExtension { get; set; } }
/// <summary> /// 图片上传参数对象 /// </summary> public class ImageUploadParameter : UploadParameterBase { /// <summary> /// 构造方法 /// </summary> /// <param name="stream"></param> /// <param name="fileName"></param> /// <param name="filenameExtension">默认支持常用图片格式</param> /// <param name="maxSize"></param> public ImageUploadParameter(Stream stream, string fileName, string[] filenameExtension = null, int maxSize = 3) { base.Stream = stream; base.FileName = fileName; base.MaxSize = maxSize; base.FilenameExtension = filenameExtension ?? new string[] { ".jpeg", ".jpg", ".gif", ".png" }; ; } /// <summary> /// 构造方法 /// </summary> /// <param name="stream"></param> /// <param name="fileName"></param> /// <param name="maxSize">单位为M</param> public ImageUploadParameter(Stream stream, string fileName, int maxSize) : this(stream, fileName, null, maxSize) { } }
３ 一批返回类型，包括对文件，图像和视频等方法的返回数据的定义
/// <summary> /// 上传文件返回对象基类 /// </summary> public abstract class UploadResultBase { /// <summary> /// 返回文件地址 /// </summary> public string FilePath { get; set; } /// <summary> /// 错误消息列表 /// </summary> public string ErrorMessage { get; set; } /// <summary> /// 是否上传成功 /// </summary> public bool IsValid { get { return string.IsNullOrWhiteSpace(ErrorMessage); } } }
/// <summary> /// 视频上传返回对象 /// </summary> public class VideoUploadResult : UploadResultBase { /// <summary> /// 上传的视频截图地址 /// </summary> public List<string> ScreenshotPaths { get; set; } /// <summary> /// 上传状态 /// </summary> public UploadStatus UploadStatus { get; set; } public VideoUploadResult() { ScreenshotPaths = new List<string>(); } /// <summary> /// 把VideoPath和ScreenshotPaths拼起来 以竖线（|）隔开 /// </summary> /// <returns></returns> public override string ToString() { StringBuilder sb = new StringBuilder(); sb.Append(FilePath); foreach (var item in ScreenshotPaths) { sb.Append("|" + item); } return sb.ToString(); } }
４ 一个使用FastDFS实现的文件上传实现类
/// <summary> /// 使用fastDFS完成文件上传 /// </summary> internal class FastDFSUploader : IFileUploader { /// <summary> /// 目录名,需要提前在fastDFS上建立 /// </summary> public string DFSGroupName { get { return "tsingda"; } } /// <summary> /// FastDFS结点 /// </summary> public StorageNode Node { get; private set; } /// <summary> /// 服务器地址 /// </summary> public string Host { get; private set; } /// <summary> /// 失败次数 /// </summary> protected int FaildCount { get; set; } public int MaxFaildCount { get; set; } public FastDFSUploader() { InitStorageNode(); MaxFaildCount = 3; } #region Private Methods private void InitStorageNode() { Node = FastDFSClient.GetStorageNode(DFSGroupName); Host = Node.EndPoint.Address.ToString(); } private List<string> CreateImagePath(string fileName) { List<string> pathList = new List<string>(); string snapshotPath = ""; //视频截图 List<string> localList = new VideoSnapshoter().GetVideoSnapshots(fileName, out snapshotPath); foreach (var item in localList) { string aImage = SmallFileUpload(item); pathList.Add(aImage); } //清除本地多余的图片，有的视频截取的图片多，有的视频截取的图片少 string[] strArr = Directory.GetFiles(snapshotPath); try { foreach (var strpath in strArr) { File.Delete(strpath); } Directory.Delete(snapshotPath); } catch (Exception ex) { Logger.Core.LoggerFactory.Instance.Logger_Info("删除图片截图异常" + ex.Message); } return pathList; } private string SmallFileUpload(string filePath) { if (string.IsNullOrEmpty(filePath)) throw new ArgumentNullException("filePath 参数不能为空"); if (!File.Exists(filePath)) throw new Exception("上传的文件不存在"); byte[] content; using (FileStream streamUpload = new FileStream(filePath, FileMode.Open, FileAccess.Read)) { using (BinaryReader reader = new BinaryReader(streamUpload)) { content = reader.ReadBytes((int)streamUpload.Length); } } string shortName = FastDFSClient.UploadFile(Node, content, "png"); return GetFormatUrl(shortName); } /// <summary> /// 文件分块上传，适合大文件 /// </summary> /// <param name="file"></param> /// <returns></returns> private string MultipartUpload(UploadParameterBase param) { Stream stream = param.Stream; if (stream == null) throw new ArgumentNullException("stream参数不能为空"); int size = 1024 * 1024; byte[] content = new byte[size]; Stream streamUpload = stream; // 第一个数据包上传或获取已上传的位置 string ext = param.FileName.Substring(param.FileName.LastIndexOf('.') + 1); streamUpload.Read(content, 0, size); string shortName = FastDFSClient.UploadAppenderFile(Node, content, ext); BeginUploadPart(stream, shortName); return CompleteUpload(stream, shortName); } /// <summary> /// 断点续传 /// </summary> /// <param name="stream"></param> /// <param name="serverShortName"></param> private void ContinueUploadPart(Stream stream, string serverShortName) { var serviceFile = FastDFSClient.GetFileInfo(Node, serverShortName); stream.Seek(serviceFile.FileSize, SeekOrigin.Begin); BeginUploadPart(stream, serverShortName); } /// <summary> /// 从指定位置开始上传文件 /// </summary> /// <param name="stream"></param> /// <param name="beginOffset"></param> /// <param name="serverShortName"></param> private void BeginUploadPart(Stream stream, string serverShortName) { try { int size = 1024 * 1024; byte[] content = new byte[size]; while (stream.Position < stream.Length) { stream.Read(content, 0, size); var result = FastDFSClient.AppendFile(DFSGroupName, serverShortName, content); if (result.Length == 0) { FaildCount = 0; continue; } } } catch (Exception ex) { Logger.Core.LoggerFactory.Instance.Logger_Info("上传文件中断！" + ex.Message); if (NetCheck()) { //重试 if (FaildCount < MaxFaildCount) { FaildCount++; InitStorageNode(); ContinueUploadPart(stream, serverShortName); } else { Logger.Core.LoggerFactory.Instance.Logger_Info("已达到失败重试次数仍没有上传成功"); ; throw ex; } } else { Logger.Core.LoggerFactory.Instance.Logger_Info("当前网络不可用"); throw ex; } } } /// <summary> /// 网络可用为True,否则为False /// </summary> /// <returns></returns> private bool NetCheck() { return NetworkInterface.GetIsNetworkAvailable(); } /// <summary> /// 拼接Url /// </summary> /// <param name="shortName"></param> /// <returns></returns> private string GetFormatUrl(string shortName) { return string.Format("http://{0}/{1}/{2}", Host, DFSGroupName, shortName); } private string CompleteUpload(Stream stream, string shortName) { stream.Close(); return GetFormatUrl(shortName); } private string GetShortNameFromUrl(string url) { if (string.IsNullOrEmpty(url)) return string.Empty; Uri uri = new Uri(url); string urlFirstPart = string.Format("http://{0}/{1}/", Host, DFSGroupName); if (!url.StartsWith(urlFirstPart)) return string.Empty; return url.Substring(urlFirstPart.Length); } #endregion #region IFileUploader 成员 /// <summary> /// 上传视频 /// </summary> /// <param name="param"></param> /// <returns></returns> public VideoUploadResult UploadVideo(VideoUploadParameter param) { VideoUploadResult result = new VideoUploadResult(); string fileName = MultipartUpload(param); if (param.IsScreenshot) { result.ScreenshotPaths = CreateImagePath(fileName); } result.FilePath = fileName; return result; } /// <summary> /// 上传普通文件 /// </summary> /// <param name="param"></param> /// <returns></returns> public FileUploadResult UploadFile(FileUploadParameter param) { var result = new FileUploadResult(); try { string fileName = MultipartUpload(param); result.FilePath = fileName; } catch (Exception ex) { result.ErrorMessage = ex.Message; } return result; } /// <summary> /// 上传图片 /// </summary> /// <param name="param"></param> /// <param name="message"></param> /// <returns></returns> public ImageUploadResult UploadImage(ImageUploadParameter param) { byte[] content; string shortName = ""; string ext = System.IO.Path.GetExtension(param.FileName).ToLower(); if (param.FilenameExtension != null && param.FilenameExtension.Contains(ext)) { if (param.Stream.Length > param.MaxSize) { return new ImageUploadResult { ErrorMessage = "图片大小超过指定大小" + param.MaxSize / 1048576 + "M，请重新选择", FilePath = shortName }; } else { using (BinaryReader reader = new BinaryReader(param.Stream)) { content = reader.ReadBytes((int)param.Stream.Length); } shortName = FastDFSClient.UploadFile(Node, content, ext.Contains('.') ? ext.Substring(1) : ext); } } else { return new ImageUploadResult { ErrorMessage = "文件类型不匹配", FilePath = shortName }; } return new ImageUploadResult { FilePath = CompleteUpload(param.Stream, shortName), }; } #endregion }
５ 一个文件上传的生产者，经典的单例模式的体现
/// <summary> /// 文件上传生产者 /// </summary> public class FileUploaderFactory { /// <summary> /// 上传实例 /// </summary> public readonly static IFileUploader Instance; private static object lockObj = new object(); static FileUploaderFactory() { if (Instance == null) { lock (lockObj) { Instance = new FastDFSUploader(); } } } }
６ 前台的文件上传控件，你可以随便选择了，它与前台是解耦的，没有什么关系，用哪种方法实现都可以，呵呵
[HttpPost] public ActionResult Index(FormCollection form) { var file = Request.Files[0]; var result = Project.FileUpload.FileUploaderFactory.Instance.UploadFile(new Project.FileUpload.Parameters.FileUploadParameter { FileName = file.FileName, Stream = file.InputStream, }); ViewBag.Path = result.FilePath; return View(); }
最后我们看一下我的Project.FileUpload的完整结构
它隶属于大叔的Project.Frameworks集合，我们在这里，对Project.FileUpload说一声：Hello FileUpload,We wait for you for a long time...
本文转自博客园张占岭（仓储大叔）的博客，原文链接：我心中的核心组件（可插拔的AOP）~分布式文件上传组件~基于FastDFS，如需转载请自行联系原博主。
