I have at production a NodeJS application running using MongoDB and Mongoose, which inside has a Mongoose Schema like:
var Product = new Schema({
"name": { type: String, required: true }
, "description": { type: String }
});
Now, as a new requirement I'm adding a new property to the Schema at my local, like this:
var Product = new Schema({
"name": { type: String, required: true }
, "description": { type: String }
, "isPublic": { type: Boolean, default: true }
});
When I restart my NodeJS process, I was expecting an update to all of my current documents (products), so now every document have a property isPublic which value is true.
What happened is no document has that new property and if I do a someProduct.Save({ isPublic: true }) it gets added.
Question: is there a way to accomplish that?,
I know I can do a $set from command line with mongo client, but I want to know if there is a way where Mongoose will add the missing property after the Schema changed on a process restart.
What happened is no document has that new property and if I do a someProduct.Save({ isPublic: true }) it gets added.
That's because the mongoose default attribute works just for new documents. There're two workarounds:
Write your code to treat documents without the isPublic property as true;
Or, as you've mentioned above, set the property manually through mongodb console.
Your best bet is to use MongoSH. Adding a new property to a Mongoose Schema will never update existing documents unless the programmer does it.
Use the updateMany command in the Mongo Shell (MongoSH):
// Get all documents in the collection, and set the field to a value
db.users.updateMany( {} ,
{ $set: {"newlyCreatedField": "defaultValue"} }
);
Related
I am very new to MONGO DB so please bear with me.I am having a problem my array of objects is not working properly .
Here is my schema
const playerSchema = new mongoose.Schema({
name: String,
stats :{
wins:Number,
losses:Number,
xp:Number
},
achievement:[
{
name:String,
date: String
}
] });
Here is my document
const fluffy = new playerModel({
"name":"nic raboy",
"stats":{
"wins":5,
"losses":10,
"xp":300
},
"achievements":[
{"name":"Massive XP","date" :"25-08-21"},
{"name":"instant loss","date":"24-08-21"}
]
});
however in mongodb atlas its only showing array...and i cant see the objects inside...
SCREENSHOT
Your schema is correct, it seems your input is wrong,
In schema definition you named it achievement, whereas in input document it is achievements. Correct this everything will work as you expected.
Explanation
The schema is expecting achievement and you inserted achievements, that is why it is shown as an empty array in the database. To avoids this kind of typos in the future, use the required flag.
const playerSchema = new mongoose.Schema({
name: String,
stats: {
wins: Number,
losses: Number,
xp: Number
},
achievements: [
{
name: {
type: String,
required : true,
},
date: {
type: String,
required : true, // required informs for missing fields
}
}
]
})
Refer this link for more on validation
You can use insertMany see the doc here.
Of course, a while loop should work find calling multiple times insertOne, though I advise you to use the insertMany() method.
If you're new to MongoDB, I strongly encourage you to have a look at MongoDB University's MongoDB basics course as well as the MongoDB for JavaScript Developers course.
This is mongoose DataModel in NodeJs
product: {type: mongoose.Schema.Types.ObjectId, ref: 'products', required: true}
But in DB, this field is having multiple type of values in documents, have String and ObjectId
I'm querying this in mongoose
{
$or: [
{
"product": "55c21eced3f8bf3f54a760cf"
}
,
{
"product": mongoose.Types.ObjectId("55c21eced3f8bf3f54a760cf")
}
]
}
But this is only fetching the documents which have that field stored as ObjectId.
Is there any way that it can fetch all the documents having both type of values either String OR ObjectId?
Help is much appreciated. Thanks
There is a schema in Mongoose, so when you query a document, it will search it by this schema type. If you change the model's product type to "string", it will fetch only documents with string IDs.
Even if there is a way to fetch either a string OR ObjectId, it's smelly to me to have such inconsistency.
I've encountered the same problem, so the solution was to standardize all documents by running a script to update them.
db.products.find().forEach(function(product) {
db.products.update({ type: product.type},{
$set:{ type: ObjectId(data.type)}
});
});
The only problem I see there is if this type field is actually an _id field. _id fields in MongoDB are immutable and they can't be updated. If that is your case, you can simply create a new document with the same (but parsed) id and remove the old one.
This is what I did: (in Robomongo)
db.getCollection('products').find().forEach(
function(doc){
var newDoc = doc;
newDoc._id = ObjectId(doc._id);
db.getCollection('products').insert(newDoc);
}
)
Then delete all documents, which id is a string:
db.getCollection('products').find().forEach(
function(doc){
db.getCollection('products').remove({_id: {$regex: ""}})
}
)
There is another way to do this. If we Update the type to Mixed then it will fetch all the documents with each type, either String or ObjectId
Define this in your Schema
mongoose.Schema.Types.Mixed
Like
product: {type: mongoose.Schema.Types.Mixed, required: true}
I have a mongoose model: (With a field that has a default)
var MySchema= new mongoose.Schema({
name: {
type: String,
required: true
},
isClever: {
type: Boolean,
default: false
}
});
I can save a model of this type by just saving a name and in mongoDB, only name can be seen in the document (and not isClever field). That's fine because defaults happen at the mongoose level. (?)
The problem I am having then is, when trying to retrieve only people called john and isClever = false:
MySchema.find({
'name' : 'john',
'isClever': false
}).exec( function(err, person) {
// person is always null
});
It always returns null. Is this something related to how defaults work with mongoose? We can't match on a defaulted value?
According to Mongoose docs, default values are applied when the document skeleton is constructed.
When you execute a find query, it is passed to Mongo when no document is constructed yet. Mongo is not aware about defaults, so since there are no documents where isClever is explicitly true, that results in empty output.
To get your example working, it should be:
MySchema.find({
'name' : 'john',
'isClever': {
$ne: true
}
})
I have the following model for users:
var UserSchema = new mongoose.Schema({
name: String,
dob: Date,
sex: String,
photo: String,
email: {type: String, index: {unique: true, required: true}},
created: {type: Date, default: Date.now}
});
var User = mongoose.model('Users', UserSchema);
As you can see the 'created' field takes a default value of the current date so that it is automatically set when a new user is created.
I use the following query when user details are posted:
User.findOneAndUpdate({email: user.email}, user, {upsert: true}, function (err, user) {
if (err) {
return callback (err);
} else {
callback(null, user);
}
});
The purpose of using findOneAndUpdate with upsert: true is to either return an existing profile, or create a new one. It also updates any fields based on the data posted.
However, the created field gets updated with the current date each time, even though the created field is not posted. How can I make sure that this field is set only once?
EDIT
An example object from the database:
{
"_id" : ObjectId("54620b38b431d48bce7cab81"),
"email" : "someone#google.com",
"__v" : 0,
"name" : "somone",
"sex" : "male"
}
It turns out that the created field is not being set even while creating a new object using upsert. Mongoose just returns the current date based on the schema even though it does not exist in the document.
So, the question now becomes: How do I make sure that using upsert creates the default value for a field not supplied in the arguments?
For adding defaults to your document if it was created with findOneAndUpdate (it didn't exist before the query) and you did not provide the field in the update you should use setDefaultsOnInsert.
When upsert and setDefaultsOnInsert are both true, the defaults will be set if the record is not found and a new one is created.
This skips the workflow of having to check if the record exists and if not then creating a new one with 'save' just to make sure defaults are set.
I have had the same issue (record created with findOneAndUpdate with upsert: true) and the default value for a field was not added to the record, even though it was in the schema.
This is only in regards to adding defaults when using findOneAndUpdate to create documents, not for skipping the update of the 'created' field.
e.g.
User.findOneAndUpdate({email: user.email}, user, {upsert: true, setDefaultsOnInsert:true}, ...)
findOneAndUpdate simply sends a MongoDB findAndModify request (see findOneAndUpdate). What this means is that it skips all the mongoose magic involved with the schema setters, getters, defaults, etc. Validation is only run on create/save so the way around this is to do a .findOne(), check existence/create a new one, and then .save().
see this issue for more discussion
EDIT:
In regards to the first question about changing the date each time, you could change the schema a bit. Get rid of the default value, and instead add this after declaring the schema:
UserSchema.pre("save", function (next) {
if (!this.created) {
this.created = new Date();
}
next();
});
That will only create a date if the created: value is not present, and should prevent it from changing the creation date each time (when using .save()).
see Mongoose middleware
We're rapidly developing an application that's using Mongoose, and our schema's are changing often. I can't seem to figure out the proper way to update a schema for existing documents, without blowing them away and completely re-recreating them from scratch.
I came across http://mongoosejs.com/docs/api.html#schema_Schema-add, which looks to be right. There's little to no documentation on how to actually implement this, making it very hard for someone who is new to MongoDB.
I simply want to add a new field called enabled. My schema definition is:
var sweepstakesSchema = new Schema({
client_id: {
type: Schema.Types.ObjectId,
ref: 'Client',
index: true
},
name: {
type: String,
default: 'Sweepstakes',
},
design: {
images: {
type: [],
default: []
},
elements: {
type: [],
default: []
}
},
enabled: {
type: Boolean,
default: false
},
schedule: {
start: {
type: Date,
default: Date.now
},
end: {
type: Date,
default: Date.now
}
},
submissions: {
type: Number,
default: 0
}
});
Considering your Mongoose model name as sweepstakesModel,
this code would add enabled field with boolean value false to all the pre-existing documents in your collection:
db.sweepstakesModel.find( { enabled : { $exists : false } } ).forEach(
function (doc) {
doc.enabled = false;
db.sweepstakesModel.save(doc);
}
)
There's nothing built into Mongoose regarding migrating existing documents to comply with a schema change. You need to do that in your own code, as needed. In a case like the new enabled field, it's probably cleanest to write your code so that it treats a missing enabled field as if it was set to false so you don't have to touch the existing docs.
As far as the schema change itself, you just update your Schema definition as you've shown, but changes like new fields with default values will only affect new documents going forward.
I was also searching for something like migrations, but didn't find it. As an alternative you could use defaults. If a key has a default and the key doesn't exist, it will use the default.
Mongoose Defaults
Default values are applied when the document skeleton is constructed. This means that if you create a new document (new MyModel) or if you find an existing document (MyModel.findById), both will have defaults provided that a certain key is missing.
I had the exact same issue, and found that using findOneAndUpdate() rather than calling save allowed us to update the schema file, without having to delete all the old documents first.
I can post a code snippet if requested.
You might use mongo shell to update the existing documents in a specific collection
db.SweeptakesModel.update({}, {$set: {"enabled": false}}, {upsert:false, multi:true})
I had a similar requirement of having to add to an existing schema when building an app with Node, and only found this (long ago posted) query to help.
The schema I added to by introducing the line in the original description of the schema and then running something similar to the following line, just the once, to update existing records:
myModelObject.updateMany( { enabled : { $exists : false } }, { enabled : false } )
'updateMany' being the function I wanted to mention here.
just addition to what Vickar was suggesting, here Mongoose Example written on Javascript (Nodejs):
const mongoose = require('mongoose');
const SweeptakesModel = mongoose.model(Constants.SWEEPTAKES,sweepstakesSchema);
SweeptakesModel.find( { enabled : { $exists : false } }).then(
function(doc){
doc.enabled = false;
doc.save();
}
)