Is it possible with mongoose use a different name, in my case uppercase 'ID', as an alias for the schema _id field?
Would I need to add a virtual or is there another way of setting this up?
Any help gratefully received thanks.
You would use a virtual attribute for that. As in:
yourSchema.virtual('ID').get(function() { return this._id; });
The easiest way is to specify alias in the schema:
let s = new Schema({
_id: { type: String, alias: "ID" }
});
This automatically creates both getter and setter, so it is possible to use ID everywhere instead of _id.
Mongoose documentation on aliases
Based on v5.11.9 mongoose documentation looks like mongoose assigns each of your schemas an id virtual getter by default which returns the document's _id field
Related
We're using collection2 (obviously with simple schema) and trying to save an array of objects to a single property on the Meteor.users collection. For example our data might be:
[
{name: "paul"},
{name: "darryn"},
{name: "tom"}
]
in reality our object is more complex
when trying to do this with $set in an update on the users collection we've either gotten 500's or managed to delete the user object entirely when turning off validation.
we've also gotten the following error a number of times:
Validation object must have at least one operator / meteor mongo
This StackOverflow Question mentions it but doesn't offer a solution that makes sense in our context.
My question is two fold. How should the schema be defined for this as we've been trying with type: [Object] which I'm not sure is right, and secondly how should the update statement be created in the method.
Any thoughts, or help would be amazing.
First define the schema for your complex object. Here I've just added age as a key:
Schema.Foo = new SimpleSchema({
name: { type: String },
age: { type: Number, min: 0 }
});
Then augment the user schema with a key whose type is an array of the type you just defined
Schema.User = new SimpleSchema({
foo: { type: [Schema.foo] },
etc...
});
Why does this query not work in Mongoskin? (where itemID is a Mongo ObjectID)
{"_id": itemID}
I know that there is truly an element that has a matching _id because if I run this same query through the MongoDB shell it works. Why doesn't it work with Mongoskin?
var ObjectId = require('mongodb').ObjectID;
Notice: the name of the factory function is ObjectID, instead of ObjectId
Then you can use:
db.collection('XXX').update({_id: ObjectId(XXX)}, {$set: {XXX : XXX}});
Well, db is a wrapped function of mongoskin:
module.exports = (function() {
return require('mongoskin').db('mongodb://localhost:27017/db_name');
})();
It turns out that mongoskin uses a different type of ObjectID than vanilla mongoDB. I was using another library to convert my string to an ObjectID, hence the confusion. Here's what worked for me to get the proper ObjectID object:
require('mongoskin').ObjectID.createFromHexString(hexString);
Hi im trying to simply remove a document from a collection using mongoose but for some strange reason I cannot get it to work.
Here is the code:
function deleteUserevent()
{console.log('in delete User Event');
models.Userevent.remove({ _id: "5214f4050acb53fe31000004"}, function(err) {
if (!err){
console.log('deleted user event!');
}
else {
console.log('error');
}
});
}
Can anyone help me out on my syntax? I know the _id is stored as new ObjectId("5214f4050acb53fe31000004") but I have tried this with no joy?
Thanks.
In MongoDB, the "_id" field of documents is of type ObjectId, as you mentioned. This is not equal to a String, so running the query
db.userevent.remove({ _id: "5214f4050acb53fe31000004"});
will not match anything, and will not remove anything. Instead, you must search for a document where the _id field is an ObjectId with that value:
db.userevents.remove({ _id: ObjectId("5214f4050acb53fe31000004")});
In mongoose, you can use the findByIdAndRemove command to remove a document with a specific _id. This command takes either an ObjectId or a String as an argument, so
query = Userevent.findByIdAndRemove("5214f4050acb53fe31000004");
should work just fine.
Just add exec() after query.
It should work like this:
await models.Userevent.findByIdAndDelete("5214f4050acb53fe31000004").exec()
I have the following 2 schemas:
Company Event:
var companyEventSchema = new Schema({
name : String,
description
date : Date,
attendees : [ { type : Schema.ObjectId, ref : 'Member' } ],
]});
And Member
var memberSchema = new Schema({
name : String,
emailAddress: String,
password :String,
created: { type: Date, default: Date.now }
});
Is the way i've ref'd Member from companyEventSchema correct?
I'm trying to do something a long the lines of a dbref.
I saw theres a separate project for that though... mongoose-dbref
However, the mongoose docs say the above provides "dbref like functionality"
Which would be more efficient?
You only need to use an actual DBRef (and mongoose-dbref) for the case where a field can contain ObjectIds that reference documents in potentially more than one collection. A DBRef is a tuple of an ObjectId, a collection name, and an optional database name.
Mongoose ref: fields, however, contain just an ObjectId and it's the Mongoose schema that defines what one collection the ObjectIds reference.
So Mongoose ref: fields are more efficient and should always be used unless you need the multi-collection reference support that DBRef provides.
For this app, I'm using Node.js, MongoDB, Mongoose & Express
So I have a Param Object that contains an array of Pivots, and I want to read certain data from the pivots as outlined below
---in models.js-------------------------
var Pivot = new Schema({
value : String
, destination : String
, counter : Number
});
var Param = new Schema({
title : String
, desc : String
, pivots : [Pivot]
});
------------- in main.js --------------
var Param = db.model('Param');
app.get('/:title/:value', function(req, res){
Param.findOne({"title":req.param('title')}, function(err, record){
console.log(record.pivots);
record.pivots.find({"value":req.param('value')}, function(err, m_pivot){
pivot.counter++;
res.redirect(m_pivot.destination);
});
record.save();
});
});
I know that the code works until console.log(record.pivots), since i got a doc collection with the right pivot documents inside.
However, there does not seem to be a find method to let me match an embedded document by the 'value' property defined in the schema. Is it possible to search through this array of embedded documents using .find() or .findOne() , and if not, is there some easy way to access it through mongoose?
varunsrin,
This should do it
app.get('/:title/:value', function(req, res) {
Param.findOne({'pivots.value': req.param('value'), "title":req.param('title')}},
function(err, record) {
record.pivot.counter++;
res.redirect(m_pivot.destination);
record.save();
});
});
Note the pluralization of the query to match the field name in your schema
You can querying using embedded document properties like this:
{'pivot.value': req.param('value')}}
Update in response to comment:
app.get('/:title/:value', function(req, res) {
Param.findOne({'pivot.value': req.param('value'), "title":req.param('title')}},
function(err, record) {
record.pivot.counter++;
res.redirect(m_pivot.destination);
record.save();
});
});
I solved it temporarily using a simple for loop to parse the object array as follows:
for (var i=0; i <record.pivots.length; i++){
if (record.pivots[i].value == req.param('value')){
res.redirect(record.pivots.destination);
}
}
However, I still think that Mongoose must have a simpler way of interacting with embedded documents - and this loop is somewhat slow, especially when the number of embedded documents grows large.
If anyone has any suggestions for a faster way to search this object array either in js or with a mongoose function, please post below.
the biggest problem with this is that if your req has some fields empty (that should act as wildcard), you will not find anything since mongo tries to match empty params as well, so searching for {"user":"bob", "color":""} is not the same as {"user":"bob", "color":"red"} or {"user":"bob"}. this means that you have to first create a query object and filter out any unused parameters before you pass it in, and if you create a query object, you can no longer do something like "user.name=..." because mongo interperets this as an error since it does not first resolve the object literal into a string.
Any ideas on this problem?
ps. You'd think it would be easy enough to make an object like:
user.name="bob"; user.color:"green"; user.signup.time="12342561"
and then just use user as a query object :/
I think you are looking for the "$in" keyword?
As in:
{a: {$in: [10, "hello"]}}
source: MongoDB Queries CheatSheet