windows7下使用MongoDB实现仓储设计

内容简介：本文给大家介绍了本人在物联网环境下基于MongoDB实现的仓储的配置信息及具体的使用示例，非常的实用，有需要的小伙伴可以参考下

简单的介绍一下，我使用 MongoDB 的场景。

我们现在的物联网环境下，有部分数据，采样频率为2000条记录/分钟，这样下来一天24*60*2000=2880000约等于300万条数据，以后必然还会增加。之前数据库使用的是mssql，对于数据库的压力很大，同时又需要保证历史查询的响应速度，这种情况下，在单表中数据量大，同时存在读写操作。不得已采用MongoDB来存储数据。如果使用MongoDB，则至少需要三台机器，两台实现读写分离，一台作为仲裁（当然条件不允许也可以不用），每台机器的内存暂时配置在16G，公司小，没办法，据说，使用这个MongoDB需要机器内存最少92G，我没有验证过，但是吃内存是公认的，所以内存绝对要保证，就算保证了，也不一定完全就没有意外发生。我们上面的这些特殊的数据是允许少量的丢失的，这些只是做分析使用的，几个月了，暂时还没出现数据丢失的情况，可能最新版本早就修复了吧，新手使用建议多看下官网上的说明。下面直接奔入主题：

一、安装部署和配置环境

1.安装部署mongo-server（V3.4）

参考点击这里进入

这个时候不要启动，接着配置config文件

2.配置Config文件

dbpath=C:/Program Files/MongoDB/Server/3.4/bin/data/db 
logpath=C:/Program Files/MongoDB/Server/3.4/bin/data/log/master.log 
pidfilepath=C:/Program Files/MongoDB/Server/3.4/bin/master.pid 
directoryperdb=true 
logappend=true 
replSet=testrs 
bind_ip=10.1.5.25
port=27016 
oplogSize=10000
noauth = true
 
storageEngine = wiredTiger
wiredTigerCacheSizeGB = 2
syncdelay = 30
wiredTigerCollectionBlockCompressor = snappy

以上是详细的配置参数，其中路径部分根据需要更改，这里设置的oplogsize大小为10G，根据业务场景进行调整，另外auth权限为null，因为设置权限会增加服务开销，影响效率，最下面几行是内存引擎，可以控制副本集同步及内存限制，防止内存泄露。

3.启动mongo-server

4.添加副本集配置

conf=
{
  "_id" : "testrs",
  "members" : [
    { "_id" : 0, "host" : "10.1.5.25:27016" },
    { "_id" : 1, "host" : "10.1.5.26:27016" },
    { "_id" : 2, "host" : "10.1.5.27:27016" }
  ]
}

rs.initiate(conf)

此时副本集集群配置已经完成，然后在命令行中输入：rs.status()，查看副本集状态，需要查看同步情况，可以输入命令：db.serverStatus().

5.设置副本集可读写

Rs.slaveOk()

6..NET操作mongo

连接设置，请参考个人封装Unitoon.Mongo代码所示。

7.性能对比

读写速度：Redis>Mongo>Mssqlserver

可容纳数据量：Mssqlserver~Mongo>Redis

存储数据类型：Mongo>Mssqlserver>Redis

Note：内存持续上升，内部没有内存回收机制，若限制内存，则可能出现查询速度变慢，数据丢失等问题，建议优化查询效率，建立索引

Db.test.ensureIndex({"username":1, "age":-1})

强制释放内存命令：db.runCommand({closeAllDatabases:1})

二、仓储设计

1.基类BaseEntity

namespace UnitoonIot.Mongo
{
  /// <summary>
  /// 实体基类，方便生成ObjId
  /// </summary>
  [Serializable]
  [ProtoContract(ImplicitFields = ImplicitFields.AllPublic)]
  //[ProtoInclude(10, typeof(NormalHistory))]
  public class BaseEntity
  {
    //[BsonRepresentation(BsonType.ObjectId)]
    public ObjectId Id { get; set; }
 
    /// <summary>
    /// 数据库名称
    /// </summary>
    public string DbName { get; set; }
 
    /// <summary>
    /// 给对象初值
    /// </summary>
    public BaseEntity()
    {
      // this.ObjId = ObjectId.GenerateNewId().ToString();
      //this.Id = ObjectId.NewObjectId().ToString();
    }
  }
}

这里需要注意时间格式，MongoDB默认时间格式为国际时间，所以在写入数据时和读取数据时，时间格式要一致，此例中没有对时间进行特殊处理，由传入的时间格式确定。

2.Repository继承接口IMongoRepository

namespace UnitoonIot.Mongo
{
  public interface IMongoRepository<TEntity> where TEntity : class
  {
  }
}

3.MongoRepository

using MongoDB.Driver;
using MongoDB.Bson;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;
using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Driver.Linq;
using System.Configuration;
using System.IO;
using UnitoonIot.AppSetting;
 
namespace UnitoonIot.Mongo
{
 
  public class MongoDb
  {
    private static string ConnectionStringHost ;
    private static string UserName ;
    private static string Password;
    private static IMongoDatabase _db = null;
    private static readonly object LockHelper = new object();
    /// <summary>
    /// mongodb初始化
    /// </summary>
    public static void Init()
    {
      ConnectionStringHost = "10.1.5.24:27016,10.1.5.24:27016,10.1.5.26:27017";
      //AppSettings.GetConfigValue("MongoHost");//"10.1.5.24:27016";
      UserName = AppSettings.GetConfigValue("MongoUserName");
      Password = AppSettings.GetConfigValue("MongoPwd");
    }
    static MongoDb()
    {
     
    }
    public static IMongoDatabase GetDb(string dbName,string options=null)
    {
     
      if (_db != null) return _db;
      lock (LockHelper)
      {
 
        if (_db != null) return _db;
        var database = dbName;
        var userName = UserName;
        var password = Password;
        var authentication = string.Empty;
        var host = string.Empty;
        if (!string.IsNullOrWhiteSpace(userName))
        {
          authentication = string.Concat(userName, ':', password, '@');
        }
        if (!string.IsNullOrEmpty(options) && !options.StartsWith("?"))
        {
          options = string.Concat('?', options);
        }
 
 
 
        host = string.IsNullOrEmpty(ConnectionStringHost) ? "localhost" : ConnectionStringHost;
        database = database ?? "testdb";
        //mongodb://[username:password@]host1[:port1][,host2[:port2],…[,hostN[:portN]]][/[database][?options]]
 
        var conString = options!=null? $"mongodb://{authentication}{host}/{database}{options}"
          : $"mongodb://{authentication}{host}/{database}";
 
        var url = new MongoUrl(conString);
        var mcs = MongoClientSettings.FromUrl(url);
        mcs.MaxConnectionLifeTime = TimeSpan.FromMilliseconds(1000);
        var client = new MongoClient(mcs);
               
        _db = client.GetDatabase(url.DatabaseName);
      }
      return _db;
    }
  }
  /// <summary>
  /// MongoDb 数据库操作类
  /// </summary>
  public class MongoRepository<T>: IMongoRepository<T> where T : BaseEntity
  {
    #region readonly field
    /// <summary>
    /// 表名
    /// </summary>
    private readonly IMongoCollection<T> _collection = null;
    /// <summary>
    /// 数据库对象
    /// </summary>
    private readonly IMongoDatabase _database;
    #endregion
 
    /// <summary>
    /// 构造函数
    /// </summary>
    public MongoRepository()
    {
      this._database = MongoDb.GetDb(Activator.CreateInstance<T>().DbName, "readPreference =secondaryPreferred ");//primaryPreferred/secondaryPreferred/nearest
      _collection = _database.GetCollection<T>(typeof(T).Name);
    }
   
 
    #region 增加
    /// <summary>
    /// 插入对象
    /// </summary>
    /// <param name="t">插入的对象</param>
    public virtual T Insert(T t)
    {
      // var flag = ObjectId.GenerateNewId();
      // t.GetType().GetProperty("Id").SetValue(t, flag);  
      //t.Time = DateTime.Now;
 
      _collection.InsertOne(t);
      return t;
    }
    /// <summary>
    /// 批量插入
    /// </summary>
    /// <param name="ts">要插入的对象集合</param>
    public virtual IEnumerable<T> InsertBatch(IEnumerable<T> ts)
    {
      _collection.InsertMany(ts);
      return ts;
    }
 
    /// <summary>
    /// 插入对象
    /// </summary>
    /// <param name="t">插入的对象</param>
    public virtual void InsertAsync(T t)
    {
      //var flag = ObjectId.GenerateNewId();
      // t.GetType().GetProperty("Id").SetValue(t, flag);
      // t.Time = DateTime.Now;
       _collection.InsertOneAsync(t);
    }
    /// <summary>
    /// 批量插入
    /// </summary>
    /// <param name="ts">要插入的对象集合</param>
    public virtual void InsertBatchAsync(IEnumerable<T> ts)
    {
       _collection.InsertManyAsync(ts);
    }
    #endregion
 
    #region 删除
    /// <summary>
    /// 删除
    /// </summary>
    /// <returns></returns>
    public virtual long Delete(T t)
    {
      var filter = Builders<T>.Filter.Eq("Id", t.Id);
      var result = _collection.DeleteOne(filter);
      return result.DeletedCount;     
    }
    /// <summary>
    /// 删除
    /// </summary>
    /// <returns></returns>
    public virtual void DeleteAsync(T t)
    {
      var filter = Builders<T>.Filter.Eq("Id", t.Id);
      _collection.DeleteOneAsync(filter);
    }
 
    /// <summary>
    /// 按条件表达式删除
    /// </summary>
    /// <param name="predicate">条件表达式</param>
    /// <returns></returns>
    public virtual long Delete(Expression<Func<T, bool>> predicate)
    {
      var result = _collection.DeleteOne(predicate);
      return result.DeletedCount;
    }
    /// <summary>
    /// 按条件表达式删除
    /// </summary>
    /// <param name="predicate">条件表达式</param>
    /// <returns></returns>
    public virtual void DeleteAsync(Expression<Func<T, bool>> predicate)
    {
      _collection.DeleteOneAsync(predicate);
    }
 
 
    /// <summary>
    /// 按条件表达式批量删除
    /// </summary>
    /// <param name="predicate">条件表达式</param>
    /// <returns></returns>
    public virtual long DeleteBatch(Expression<Func<T, bool>> predicate)
    {
      var result = _collection.DeleteMany(predicate);
      return result.DeletedCount;
    }
    /// <summary>
    /// 按条件表达式批量删除
    /// </summary>
    /// <param name="predicate">条件表达式</param>
    /// <returns></returns>
    public virtual void DeleteBatchAsync(Expression<Func<T, bool>> predicate)
    {
       _collection.DeleteManyAsync(predicate);
    }
 
    /// <summary>
    /// 按检索条件删除
    /// 建议用Builders<T>构建复杂的查询条件
    /// </summary>
    /// <param name="filter">条件</param>
    /// <returns></returns>
    public virtual long Delete(FilterDefinition<T> filter)
    {
      var result = _collection.DeleteOne(filter);
      return result.DeletedCount;
    }
 
    /// <summary>
    /// 按检索条件删除
    /// 建议用Builders<T>构建复杂的查询条件
    /// </summary>
    /// <param name="filter">条件</param>
    /// <returns></returns>
    public virtual void DeleteAsync(FilterDefinition<T> filter)
    {
       _collection.DeleteOneAsync(filter);
    }
    #endregion
 
    #region 修改
    /// <summary>
    /// 修改(Id不变)
    /// </summary>  
    /// <returns></returns>
    public virtual long Update(T t)
    {     
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id",t.Id);
      var update = _collection.ReplaceOne(filter, t, new UpdateOptions() { IsUpsert = true });
      return update.ModifiedCount;
    }
    /// <summary>
    /// 修改(Id不变)
    /// </summary>  
    /// <returns></returns>
    public virtual void UpdateAsync(T t)
    {
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id", t.Id);
       _collection.ReplaceOneAsync(filter, t, new UpdateOptions() { IsUpsert = true });
       
    }
 
 
    /// <summary>
    /// 用新对象替换新文档
    /// </summary>
    /// <param name="filter">查询条件</param>
    /// <param name="t">对象</param>
    /// <returns>修改影响文档数</returns>
    public virtual long Update(Expression<Func<T, bool>> filter, T t)
    {
      var update = _collection.ReplaceOne(filter, t, new UpdateOptions() { IsUpsert = true });
      return update.ModifiedCount;
    }
 
 
    /// <summary>
    /// 用新对象替换新文档
    /// </summary>
    /// <param name="filter">查询条件</param>
    /// <param name="t">对象</param>
    /// <returns>修改影响文档数</returns>
    public virtual long Update(FilterDefinition<T> filter, T t)
    {
      var update = _collection.ReplaceOne(filter, t, new UpdateOptions() { IsUpsert = true });
      return update.ModifiedCount;
    }
    /// <summary>
    /// 用新对象替换新文档
    /// </summary>
    /// <param name="filter">查询条件</param>
    /// <param name="t">对象</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateAsync(Expression<Func<T, bool>> filter, T t)
    {
      _collection.ReplaceOneAsync(filter, t, new UpdateOptions() { IsUpsert = true });
      
    }
    /// <summary>
    /// 用新对象替换新文档
    /// </summary>
    /// <param name="filter">查询条件</param>
    /// <param name="t">对象</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateAsync(FilterDefinition<T> filter, T t)
    {
       _collection.ReplaceOneAsync(filter, t, new UpdateOptions() { IsUpsert = true });
       
    }
    /// <summary>
    /// 根据Id和条件文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="id">对象Id</param>
    /// <returns>修改影响文档数</returns>
    public virtual long Update(string id, UpdateDefinition<T> update)
    {
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id", new ObjectId(id));
      var result = _collection.UpdateOne(filter, update, new UpdateOptions() { IsUpsert = true });
      return result.ModifiedCount;
    }
    /// <summary>
    /// 根据Id和条件文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="id">对象Id</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateAsync(string id, UpdateDefinition<T> update)
    {
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id", new ObjectId(id));
      _collection.UpdateOneAsync(filter, update, new UpdateOptions() { IsUpsert = true });    
    }
    /// <summary>
    /// 根据条件修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual void Update(UpdateDefinition<T> update,Expression<Func<T, bool>> filter)
    {
      _collection.UpdateOne(filter, update, new UpdateOptions() { IsUpsert = true });
    }
    /// <summary>
    /// 根据条件修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual long Update(UpdateDefinition<T> update, FilterDefinition<T> filter)
    {
      var result = _collection.UpdateOne(filter, update, new UpdateOptions() { IsUpsert = true });
      return result.ModifiedCount;
    }
    /// <summary>
    /// 根据条件修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateAsync(UpdateDefinition<T> update, Expression<Func<T, bool>> filter)
    {
      _collection.UpdateOneAsync(filter, update, new UpdateOptions() { IsUpsert = true });
    }
    /// <summary>
    /// 根据条件修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateAsync(UpdateDefinition<T> update, FilterDefinition<T> filter)
    {
       _collection.UpdateOneAsync(filter, update, new UpdateOptions() { IsUpsert = true });
    }
 
    /// <summary>
    /// 根据条件批量修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual long UpdateBatch(UpdateDefinition<T> update, Expression<Func<T, bool>> filter)
    {
      var result = _collection.UpdateMany(filter, update, new UpdateOptions() { IsUpsert = true });
      return result.ModifiedCount;
    }
 
    /// <summary>
    /// 根据条件批量修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual long UpdateBatch(UpdateDefinition<T> update, FilterDefinition<T> filter)
    {
      var result = _collection.UpdateMany(filter, update, new UpdateOptions() { IsUpsert = true });
      return result.ModifiedCount;
    }
    /// <summary>
    /// 根据条件批量修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateBatchAsync(UpdateDefinition<T> update, Expression<Func<T, bool>> filter)
    {
       _collection.UpdateManyAsync(filter, update, new UpdateOptions() { IsUpsert = true });
    }
 
    /// <summary>
    /// 根据条件批量修改文档
    /// </summary>
    /// <param name="update">修改条件-形如：Builders/<T/>.Update.Set(filed, value)</param>
    /// <param name="filter">查询条件Builders/<T/>.Filter.Eq(filed, value)</param>
    /// <returns>修改影响文档数</returns>
    public virtual void UpdateBatchAsync(UpdateDefinition<T> update, FilterDefinition<T> filter)
    {
      _collection.UpdateManyAsync(filter, update, new UpdateOptions() { IsUpsert = true });
    }
    #endregion
 
    #region 查询 
 
    #region GetCollection
 
    /// <summary>
    /// 获取操作对象的IMongoCollection集合,强类型对象集合
    /// </summary>
    /// <returns></returns>
    public virtual IMongoCollection<T> GetCollection()
    {
      return _database.GetCollection<T>(typeof(T).Name);
    }
 
    #endregion
 
    #region GetSingle
    /// <summary>
    /// 查询数据库,检查是否存在指定ID的对象
    /// </summary>
    /// <param name="id">对象的ID值</param>
    /// <returns>存在则返回指定的对象,否则返回Null</returns>
    public virtual T GetById(string id)
    {
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id", new ObjectId(id));
      var data = _collection.Find(filter).FirstOrDefault();
      return data;
    }
    /// <summary>
    /// 查询数据库,检查是否存在指定ID的对象
    /// </summary>
    /// <param name="id">对象的ID值</param>
    /// <returns>存在则返回指定的对象,否则返回Null</returns>
    public virtual async Task<T> GetAsyncById(string id)
    {
      var filterBuilder = Builders<T>.Filter;
      var filter = filterBuilder.Eq("Id", new ObjectId(id));
      var data = await _collection.FindAsync(filter);
      return await data.SingleOrDefaultAsync();
    }
    /// <summary>
    /// 查询数据
    /// </summary>
    /// <param name="filter">过滤条件</param>
    /// <returns></returns>
    public virtual T Get(FilterDefinition<T> filter)
    {
      return _collection.Find(filter).FirstOrDefault();
    }
    /// <summary>
    /// 查询数据
    /// </summary>
    /// <param name="filter">条件表达式</param>
    /// <returns></returns>
    public virtual T Get(Expression<Func<T,bool>> filter)
    {
      return _collection.Find(filter).FirstOrDefault();
    }
    /// <summary>
    /// 查询数据
    /// </summary>
    /// <param name="filter">过滤条件</param>
    /// <returns></returns>
    public virtual async Task<T> GetAsync(FilterDefinition<T> filter)
    {
      var data = await _collection.FindAsync(filter);
      return await data.SingleOrDefaultAsync();
    }
    /// <summary>
    /// 查询数据
    /// </summary>
    /// <param name="filter">条件表达式</param>
    /// <returns></returns>
    public virtual async Task<T> GetAsync(Expression<Func<T, bool>> filter)
    {
      var data = await _collection.FindAsync(filter);
      return await data.SingleOrDefaultAsync();
    }
 
 
    #endregion
 
    #region GetMany
    /// <summary>
    /// 查询部分数据
    /// </summary>
    /// <param name="filter">过滤条件</param>
    /// <returns></returns>
    public virtual IEnumerable<T> GetMany(FilterDefinition<T> filter)
    {
      return _collection.Find(filter).ToEnumerable();
    }
 
    /// <summary>
    /// 查询部分数据
    /// </summary>
    /// <param name="filter">条件表达式</param>
    /// <returns></returns>
    public virtual IEnumerable<T> GetMany(Expression<Func<T,bool>> filter)
    {
      //return _collection.AsQueryable().Where(filter).ToList();
      //return _collection.AsQueryable().Where(filter);
      return _collection.Find(filter).ToEnumerable(); //.ToEnumerable(); 
    }
 
    /// <summary>
    /// 查询部分数据
    /// </summary>
    /// <param name="filter">过滤条件</param>
    /// <returns></returns>
    public virtual async Task<IEnumerable<T>> GetManyAsync(FilterDefinition<T> filter)
    {
      var data = await _collection.FindAsync(filter);
      return await data.ToListAsync();
    }
 
    /// <summary>
    /// 查询部分数据
    /// </summary>
    /// <param name="filter">过滤条件</param>
    /// <returns></returns>
    public virtual async Task<IEnumerable<T>> GetManyAsync(Expression<Func<T, bool>> filter)
    {
      var data = await _collection.FindAsync(filter);
      return await data.ToListAsync();
    }
     
    #endregion
 
    #region GetAll
 
    /// <summary>
    /// 查询所有记录，复杂查询直接用Linq处理(避免全表扫描)
    /// </summary>
    /// <returns>要查询的对象</returns>
    public virtual IEnumerable<T> GetAll()
    {
      var data = _collection.AsQueryable();
      return data.ToEnumerable();
    }
    /// <summary>
    /// 查询所有记录，复杂查询直接用Linq处理(避免全表扫描)
    /// </summary>
    /// <returns>要查询的对象</returns>
    public virtual async Task<IEnumerable<T>> GetAllAsync()
    {
      var data = _collection.AsQueryable();
      return await data.ToListAsync();
    }
 
    /// <summary>
    /// 查询所有记录，复杂查询直接用Linq处理(避免全表扫描)
    /// </summary>
    /// <returns>要查询的对象</returns>
    public virtual IQueryable<T> GetAllQueryable()
    {
      return _collection.AsQueryable();
    }
 
    #endregion
 
    #region MapReduce
    /// <summary> 
    /// MapReduce
    /// </summary>   
    /// <returns>返回一个List列表数据</returns> 
    public IEnumerable<T> GetMap(BsonJavaScript map,BsonJavaScript reduce)
    {
      return _collection.MapReduce<T>(map,reduce).ToList();
    }
 
 
    #endregion
 
    #endregion
  }
 
}

好了，就介绍到这里。

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