Aggregate with count of sub documents matching the condition and grouping

问题

I've collections of documents as like as below:

{
    "_id" : ObjectId("55d4410544c96d6f6578f893"),
    "executionProject" : "Project1",
    "suiteList" : [ 
        {
            "suiteStatus" : "PASS"
        }
    ],
    "runEndTime" : ISODate("2015-08-19T08:40:47.049Z"),
    "runStartTime" : ISODate("2015-08-19T08:40:37.621Z"),
    "runStatus" : "PASS",
    "__v" : 1
}

{
    "_id" : ObjectId("55d44eb4c0422e7b8bffe76b"),
    "executionProject" : "Project1",
    "suiteList" : [ 
        {
            "suiteStatus" : "PASS"
        }
    ],
    "runEndTime" : ISODate("2015-08-19T09:39:13.528Z"),
    "runStartTime" : ISODate("2015-08-19T09:39:00.406Z"),
    "runStatus" : "PASS",
    "__v" : 1
}

{
    "_id" : ObjectId("55d44f0bc0422e7b8bffe76f"),
    "executionProject" : "Project1",
    "suiteList" : [ 
        {
            "suiteStatus" : "FAIL"
        }
    ],
    "runEndTime" : ISODate("2015-08-19T09:46:31.108Z"),
    "runStartTime" : ISODate("2015-08-19T09:40:27.377Z"),
    "runStatus" : "PASS",
    "__v" : 1
}

{
    "_id" : ObjectId("55d463d0c0422e7b8bffe789"),
    "executionProject" : "Project2",
    "suiteList" : [ 
        {
            "suiteStatus" : "PASS"
        },
        {
            "suiteStatus" : "PASS"
        }
    ],
    "runEndTime" : ISODate("2015-08-19T11:09:52.537Z"),
    "runStartTime" : ISODate("2015-08-19T11:09:04.539Z"),
    "runStatus" : "FAIL",
    "__v" : 1
}

{
    "_id" : ObjectId("55d464ebc0422e7b8bffe7c2"),
    "executionProject" : "Project3",
    "suiteList" : [ 
        {
            "suiteStatus" : "FAIL"
        }
    ],
    "runEndTime" : ISODate("2015-08-19T11:18:41.460Z"),
    "runStartTime" : ISODate("2015-08-19T11:13:47.268Z"),
    "runStatus" : "FAIL",
    "__v" : 10
} 

And I'm expecting output as follows:

[
    {
        "executionProject": "Project1",
        "suite-pass": 0,
        "suite-fail": 1,
        "runEndTime": ISODate("2015-08-19T09:46:31.108Z")
    },
    {
        "executionProject": "Project2",
        "suite-pass": 2,
        "suite-fail": 0,
        "runEndTime": ISODate("2015-08-19T11:09:52.537Z")
    },
    {
        "executionProject": "Project3",
        "suite-pass": 0,
        "suite-fail": 1,
        "runEndTime": ISODate("2015-08-19T11:18:41.460Z")
    },
]

I want to group by project and order by runEndTime and show the pass and fail counts of suiteList.

I tried this as suggested by Blakes in Mongodb: Group by element and show the sub-document count based on condition and sort the document by date:

db.testruns.aggregate([
      { "$sort": { "runEndTime": 1 } },
      { "$group": {
      "_id": "$executionProject",
        "suite-pass": {
          "$last": {
            "$cond": [
              { "$anyElementTrue": {
                "$map": {
                  "input": "$suiteList",
                  "as": "suite",
                  "in": {
                    "$eq": [ "$$suite.suiteStatus", "PASS" ]
                  }
                }
              }},
              1,
              0
            ]
          }
        },
        "suite-fail": {
          "$last": {
            "$cond": [
              { "$anyElementTrue": {
                "$map": {
                  "input": "$suiteList",
                  "as": "suite",
                  "in": {
                    "$eq": [ "$$suite.suiteStatus", "FAIL" ]
                  }
                }
              }},
              1,
              0
            ]
          }
        },
        "runEndTime": { "$last": "$runEndTime" }
      }},
      { "$sort": { "runEndTime": 1 } }
    ]);

I was expecting the suite-pass count for Project2 as 2 since there are 2 elements in suiteList, but it returns 1.

回答1:

You should have read the answer properly, as there already was another alternate listing and explanation of why the expected result you want from the one you used would be different.

Instead you want this one, which respects the possible multiple "PASS" or "FAIL":

  Model.aggregate(
    [
      { "$sort": { "executionProject": 1, "runEndTime": 1 } },
      { "$group": {
        "_id": "$executionProject",
        "suiteList": { "$last": "$suiteList" },
        "runEndTime": { "$last": "$runEndTime" }
      }},
      { "$unwind": "$suiteList" },
      { "$group": {
        "_id": "$_id",
        "suite-pass": { 
          "$sum": {
            "$cond": [
              { "$eq": [ "$suiteList.suiteStatus", "PASS" ] },
              1,
              0
            ]
          }
        },
        "suite-fail": { 
          "$sum": {
            "$cond": [
              { "$eq": [ "$suiteList.suiteStatus", "FAIL" ] },
              1,
              0
            ]
          }
        },
        "runEndTime": {"$first": "$runEndTime"}
      }},
      { "$sort": { "runEndTime": 1 }}
    ],
    function(err,result) {

    }
  );

Which is sort of a "combination" of approaches. The first is to get the "last" by runTime as you were expecting. The next is to break down the array and this time actually "sum up" the possible occurances of pass or fail, rather than just record a 1 for either pass or fail in the array, the actual "pass" or "fail" are counted.

With results:

{
        "_id" : "Project1",
        "suite-pass" : 0,
        "suite-fail" : 1,
        "runEndTime" : ISODate("2015-08-19T09:46:31.108Z")
}
{
        "_id" : "Project2",
        "suite-pass" : 2,
        "suite-fail" : 0,
        "runEndTime" : ISODate("2015-08-19T11:09:52.537Z")
}
{
        "_id" : "Project3",
        "suite-pass" : 0,
        "suite-fail" : 1,
        "runEndTime" : ISODate("2015-08-19T11:18:41.460Z")
}

回答2:

Unwind suiteList and used $sum in group as below :

db.testruns.aggregate({
    "$unwind": "$suiteList"
}, {
    "$group": {
        "_id": "$executionProject",
        "suite-pass": {
            "$sum": {
                "$cond": {
                    "if": {
                        "$eq": ["$suiteList.suiteStatus", "PASS"]
                    },
                    "then": 1,
                    "else": 0
                }
            }
        },
        "suite-fail": {
            "$sum": {
                "$cond": {
                    "if": {
                        "$eq": ["$suiteList.suiteStatus", "FAIL"]
                    },
                    "then": 1,
                    "else": 0
                }
            }
        },
        "runEndTime": {
            "$last": "$runEndTime"
        }
    }
}, {
    "$sort": {
        "runEndTime": 1
    }
})

来源：https://stackoverflow.com/questions/32197955/aggregate-with-count-of-sub-documents-matching-the-condition-and-grouping