MongoDB-Repository-Sample

MongoDataProvider.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using MongoDB.Bson;
using MongoDB.Driver;
using MongoDB.Driver.Builders;

public class MongoObject
{
    public ObjectId _id { get; set; }
}

public class MongoDataProvider
{
    MongoServer server;
    MongoDatabase database;

    public MongoDataProvider()
        : this("mongodb://localhost", "MongoRepoDb")
    {
    }

    public MongoDataProvider(string connectionString, string databaseName)
    {
        server = MongoServer.Create(connectionString);
        database = server.GetDatabase(databaseName);
    }

    public bool InsertObject<T>(T t) where T : MongoObject
    {
        var collection = GetCollection<T>();
        var result = collection.Insert(t);
        return result != null ? result.Ok : false;
    }

    public bool UpdateObject<T>(T t) where T : MongoObject
    {
        var query = Query.EQ("_id", t._id);
        var collection = GetCollection<T>();
        var bson = t.ToBsonDocument();
        var update = new UpdateDocument(bson.Elements);
        var result = collection.Update(query, update);
        return result != null ? result.Ok : false;
    }

    public bool DeleteObject<T>(T t) where T : MongoObject
    {
        var collection = GetCollection<T>();
        var query = Query.EQ("_id", t._id);
        var result = collection.Remove(query);
        return result != null ? result.Ok : false;
    }

    public T GetObject<T>(ObjectId _id) where T : MongoObject
    {
        var collection = GetCollection<T>();
        var query = Query.EQ("_id", _id);
        return collection.FindAs<T>(query).SingleOrDefault();
    }

    public List<T> GetAllObjects<T>() where T : MongoObject
    {
        var collection = GetCollection<T>();
        return collection.FindAllAs<T>().ToList();
    }

    public List<T> QueryObject<T>(Expression<Func<T, bool>> exp) where T : MongoObject
    {
        var collection = GetCollection<T>();

        var query = GetQuery(exp.Body);

        return collection.FindAs<T>(query).ToList();
    }

    #region Helpers

    private IMongoQuery GetQuery(Expression exp)
    {
        IMongoQuery query, leftQuery, rightQuery;
        Expression left, right;
        string property;
        object value;

        switch (exp.NodeType)
        {
            case ExpressionType.Equal:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.EQ(property, value.ToString());

                break;
            case ExpressionType.NotEqual:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.NE(property, value.ToString());

                break;
            case ExpressionType.AndAlso:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                leftQuery = GetQuery(left);
                rightQuery = GetQuery(right);

                query = Query.And(leftQuery, rightQuery);

                break;
            case ExpressionType.OrElse:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                leftQuery = GetQuery(left);
                rightQuery = GetQuery(right);

                query = Query.Or(leftQuery, rightQuery);

                break;
            case ExpressionType.GreaterThan:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.GT(property, value.ToString());

                break;
            case ExpressionType.GreaterThanOrEqual:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.GTE(property, value.ToString());

                break;
            case ExpressionType.LessThan:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.LT(property, value.ToString());

                break;
            case ExpressionType.LessThanOrEqual:

                left = (exp as BinaryExpression).Left;
                right = (exp as BinaryExpression).Right;

                property = (left as MemberExpression).Member.Name;
                value = (right as ConstantExpression).Value;

                query = Query.LTE(property, value.ToString());

                break;

            default:
                throw new Exception(exp.NodeType.ToString() + " not supported for now");
        }

        return query;
    }

    private MongoCollection GetCollection<T>() where T : MongoObject
    {
        return database.GetCollection((typeof(T)).Name);
    }

    #endregion
}