MongoDB 使用GridFS儲存檔案

      上篇文章說了一下怎麼試用MongoDB來做replication，但是我是通過BSON Object來儲存檔案，這有個局限，就是如果檔案超過4m就會拋出超過最大檔案的異常。

根據官網介紹，BSON objects in MongoDB are limited to 4MB in size.   http://www.mongodb.org/display/DOCS/GridFS

 

因此重新寫了那個操作類，使用GridFS來儲存檔案，代碼很簡單，但開始接觸弄了比較長時間，有一個問題一直解決不了，我希望自己產生一個Guid的 _id 而不是mongodb產生的_id，但是一直解決不了，希望哪個高手看到指點一下，謝謝！

 

這個是使用Mongodb官網提供的用戶端寫的：

 

using System;using System.Collections.Generic;using System.Text;using System.IO;using MongoDB.Driver;using MongoDB.Driver.Builders;using MongoDB.Bson;using MongoDB.Driver.GridFS;namespace FileUtility{    public class DocUtility    {        private string connStr = "";        public string ConnStr        {            get             {                if (string.IsNullOrEmpty(connStr))                {                    throw new ArgumentNullException("Connection string did not specify!");                }                return connStr;            }        }        public DocUtility()        {            connStr = System.Configuration.ConfigurationManager.AppSettings["FileDb"];        }        public DocUtility(string connectionString)        {            this.connStr = connectionString;        }        /// <summary>        /// add a document to mongodb        /// </summary>        /// <param name="content">document bytes array</param>        /// <returns>the unique identity filename in mongodb</returns>        public string AddDoc(byte[] content)        {            MongoServer server = MongoServer.Create(this.ConnStr);            try            {                string filename = Guid.NewGuid().ToString();                server.Connect();                MongoDatabase db = server.GetDatabase("ecDocs");                MongoGridFS fs = new MongoGridFS(db, new MongoGridFSSettings() { Root="ecDocs" });                MongoGridFSFileInfo info = new MongoGridFSFileInfo(fs, filename);                using (MongoGridFSStream gfs = info.Create())                {                    gfs.Write(content, 0, content.Length);                }                return filename;            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (server != null)                    server.Disconnect();            }        }        /// <summary>        /// delete doc from mongodb        /// </summary>        /// <param name="filename">the unique identity filename</param>        public string DeleteDoc(string filename)        {            MongoServer server = MongoServer.Create(this.ConnStr);            try            {                server.Connect();                MongoDatabase db = server.GetDatabase("ecDocs");                MongoGridFS fs = new MongoGridFS(db, new MongoGridFSSettings() { Root = "ecDocs" });                fs.Delete(filename);                return filename;            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (server != null)                    server.Disconnect();            }        }        /// <summary>        /// get document bytes array from mongodb        /// </summary>        /// <param name="filename">unique filename</param>        /// <returns>bytes array</returns>        public byte[] GetDoc(string filename)        {            MongoServer server = MongoServer.Create(this.ConnStr);            try            {                server.Connect();                MongoDatabase db = server.GetDatabase("ecDocs");                MongoGridFS fs = new MongoGridFS(db,new MongoGridFSSettings() { Root="ecDocs" });                byte[] bytes = null;                using (MongoGridFSStream gfs = fs.Open(filename, FileMode.Open))                {                    bytes = new byte[gfs.Length];                    gfs.Read(bytes, 0, bytes.Length);                }                return bytes;            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (server != null)                    server.Disconnect();            }        }    }}

 

下面這個類是使用Samus的用戶端：

 

using System;using System.Collections.Generic;using System.Linq;using System.Text;using MongoDB;using MongoDB.GridFS;namespace FileUtilitySamus{    public class DocUtility    {        private string connStr = "";        public string ConnStr        {            get            {                if (string.IsNullOrEmpty(connStr))                {                    throw new ArgumentNullException("Connection string did not specify!");                }                return connStr;            }        }        public DocUtility()        {            connStr = System.Configuration.ConfigurationManager.AppSettings["FileDb"];        }        public DocUtility(string connectionString)        {            this.connStr = connectionString;        }        /// <summary>        /// add a document to mongodb        /// </summary>        /// <param name="content">document bytes array</param>        /// <returns>the unique identity filename in mongodb</returns>        public string AddDoc(byte[] content)        {            using (Mongo mongo = new Mongo(this.ConnStr))            {                try                {                    string filename = Guid.NewGuid().ToString();                    mongo.Connect();                    IMongoDatabase db = mongo.GetDatabase("ecDoc");                    GridFile fs = new GridFile(db, "ecDoc");                    GridFileInfo info = new GridFileInfo(db, "ecDoc", filename);                    using (GridFileStream gfs = info.Create())                    {                        gfs.Write(content, 0, content.Length);                    }                    return filename;                }                catch (Exception ex)                {                    throw ex;                }            }        }        /// <summary>        /// delete doc from mongodb        /// </summary>        /// <param name="filename">the unique identity filename</param>        public void DeleteDoc(string filename)        {            using (Mongo mongo = new Mongo(this.ConnStr))            {                try                {                    mongo.Connect();                    IMongoDatabase db = mongo.GetDatabase("ecDoc");                    GridFile fs = new GridFile(db, "ecDoc");                    fs.Delete(new Document("filename", filename));                                    }                catch (Exception ex)                {                    throw ex;                }            }        }        /// <summary>        /// get document bytes array from mongodb        /// </summary>        /// <param name="filename">unique filename</param>        /// <returns>bytes array</returns>        public byte[] GetDoc(string filename)        {            using (Mongo mongo = new Mongo(this.ConnStr))            {                try                {                    mongo.Connect();                    IMongoDatabase db = mongo.GetDatabase("ecDoc");                    GridFile fs = new GridFile(db, "ecDoc");                    GridFileStream gfs = fs.OpenRead(filename);                    byte[] bytes = new byte[gfs.Length];                    gfs.Read(bytes, 0, bytes.Length);                    return bytes;                }                catch (Exception ex)                {                    if (ex.GetType() == typeof(System.IO.DirectoryNotFoundException))                        throw new System.IO.FileNotFoundException("File not found :" + filename);                    else                        throw ex;                }            }        }    }}

不知道兩個用戶端的效能相比如何？希望測試過的同學分享一下。