Mongodb blog status based on author example

Mongodb blog status based on author example

//http://stackoverflow.com/questions/31649223/mongodb-aggregate-blog-post-based-on-status/31649870#31649870
//Also refer this http://stackoverflow.com/questions/12700836/mongodb-aggregate-query-equivalent-to-postsgresql

How to get the output like this

[{
     "_id" : ObjectId('dshe1hhdsa12dashe21dqs'),
     "blogId" : 'dhsad78sa6dsa66ds6ds6ds8ds',
     "published" : 10,
     "approved" : 15,
     "pending" : 5
    },
    {
     "_id" : ObjectId('dshe1hhdsa12dashe21dqs'),
     "blogId" : 'dhsad78sa6dsa66ds6ds6ds8ds',
     "published" : 10,
     "approved" : 15,
     "pending" : 5
    }]
    
Query : 

var query = [
      { 
        $match: 
          { 
            status: { $in : ['Published', 'Approved', 'Pending']}
          }
      },
      {
        $group: {
          _id: { 
            blogId:"$blogId"
          }, 
          published: {
            $sum:{
              $cond:[
                {$eq:["$status","Published"]}, 
                1, 
                0
              ]
            }
          }, 
          approved: {
            $sum: { 
              $cond:[
                {$eq:["$status","Approved"]}, 
                1, 
                0
              ]
            }
          },
          pending: {
            $sum: { 
              $cond:[
                {$eq:["$status","Pending"]}, 
                1, 
                0
              ]
            }
          }  
        } 
      },
      {
        $project: {
         _id: 0, 
         blogId: "$_id.blogId", 
         published: "$published", 
         approved: "$approved",
         pending: "$pending"
        }
      }
    ];

    db.blog.aggregate(query);