Get Group list with Member data where User is not member or owner of group - mongodb

Question

I have Two Collection like following, I'm confused with the query can any one please help to solve,
Group:
var WorkKrewSchema = mongoose.Schema({
content_detail: {
name: String,
description: String
},
business_info: {
name: String,
address: String,
city: String,
state: String,
zipcode: String,
website: String,
starting_hours: Date,
ending_hours: Date,
days: Array
},
created_by: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User'
},
created_on: Date,
updated_on: Date
});
Members:
var KrewPartnerSchema = mongoose.Schema({
Work_krew_id: {
type: mongoose.Schema.Types.ObjectId
},
members: [
{
refrence_id: mongoose.Schema.Types.ObjectId,
is_sub_admin: {
type: Boolean,
default: false
},
status: {
type: String,
enum: ['accepted', 'declined', 'pending']
},
date_of_join: Date
}
]
});
get Groups where:
User is not owner of that group as well as not member,
If user is member then status should be Pending

Answer 1

Assuming you have a collection Groups that contains documents of the following form:
{
"_id" : ObjectId("598311f3c63f57ec3dcac86f"),
"grp_name" : "groupA",
"created_by" : "userA"
}
...and a collection Members that contains documents of the following form:
{
"_id" : ObjectId("59831310c63f57ec3dcac891"),
"grp_id" : ObjectId("598311f3c63f57ec3dcac86f"),
"members" : [
{
"user_id" : "UserY",
"status" : "pending"
},
{
"user_id" : "UserA",
"status" : "pending"
},
{
"user_id" : "UserB",
"status" : "approved"
}
]
}
...you can run the following query for a user called "UserA" which should do what you need:
db.getCollection('Members').aggregate(
{
$lookup:
{
from: "Groups",
localField: "grp_id",
foreignField: "_id",
as: "group"
}
},
{
$match:
{
$or:
[
{
"members.user_id": { $ne: "UserA" },
"group.0.created_by": { $ne: "UserA" }
},
{
"members":
{
$elemMatch:
{
"user_id": "UserA",
"status": "pending"
}
}
}
]
}
}
)
I would suggest, though, that you merge those two collections into one. A group document should simply contain all its members in which case you wouldn't need the $lookup stuff and could get away with simple queries (without the aggregation framework).