Retrieve only the queried element in an object array

Question

I have a collection with organizations. Each organization has members. I want to run query to check if a user is a member of that organization.

I tried this:

mongoose.model('organization').find({orgId: paramOrgId}, function(err, organization){
      organization.find({'members.user':req.user._id}, function(err, user){
        if(!user) res.send(401) //The user is not a member in organization

        if(user) res.send(200);

      });

    }
    return res.send(401);
  });

Apparently you don't have 'find' on callback. How should I do this instead?

Example of organization doc:

> db.organizations.find().forEach(printjson);
{
    "_id" : ObjectId("5381d5d11409f125475fcc90"),
    "orgId" : 5,
    "title" : "ExampleCorp",
    "members" : [
        {
            "tier" : 1,
            "user" : ObjectId("5381d5d11409f125475fcc8c")
        },
        {
            "tier" : 2,
            "user" : ObjectId("5381d5d11409f125475fcc8d")
        },
        {
            "tier" : 3,
            "user" : ObjectId("5381d5d11409f125475fcc8e")
        }
    ]
}

Can you edit your question to include an example `organization` document? — JohnnyHK, May 25 '14 at 14:47
I think this can only be done in single query. See this http://stackoverflow.com/questions/3985214/mongodb-extract-only-the-selected-item-in-array/12241733#12241733 — Foreever, May 25 '14 at 18:31

score 0 · Accepted Answer · answered May 25 '14 at 15:20

Here it is in one query if you just want to check if a user is a member of an organization.

// Use findOne so that it returns one document instead of a collection
mongoose.model('organization').findOne({
    // Instead of querying twice, just set both conditions
    'orgId': paramOrgId,
    'members.user':req.user._id
}, 
'_id', // We'll just select the _id field. We don't need the whole organization document
function (err, org) {
    if (err)  
        return res.send(500); // Error!

    if (org) 
        return res.send(200);
    else
        return res.send(401);
});

Retrieve only the queried element in an object array

1 Answers1