var newsfeed = db.collection('newsfeed');
newsfeed.findAndModify({
_id: mongodb.ObjectId(newsfeedId)
}, {
new: true
}, {
$set: newsfeed
}, function(err, result) {
if (err) {
return reject(err);
} else {
return resolve(result.value);
}
});
I get a cyclic dependency error when i run this query on mongodb, ive read through other solutions presented in stackoverflow but cant seem to fix this error ..
this is the error message i see
You are setting the newsfeed object back to newsfeed collection. Try to include the field which needs to be updated instead of whole object.
you may added some schema restrictions on model with type
try to console the newsfeed and make sure data you are trying to update matching with schema field type
Related
I currently have an upsert function in my project which works but my main problem is that it creates another instance of the record, and updates the new instance instead. This is the code:
router.route('/carousel/update/:_id').put(function(req, res) {
var id;
if(req.params._id == 'undefined'){
id = crypto.randomBytes(12).toString('hex');
}
else {
id = ObjectId(req.params._id)
}
db.collection('home').updateOne({"_id": id},
{$set: req.body}, {upsert: true}, (err, results) => {
if (err) throw err;
res.send(results)
console.log(req.body)
});
});
The problem:
1. It mystifies me that mongoDB takes my crypto generated _id and takes it as the new _id for the upserted document. Why is that? When {upsert: true}, isn't mongoDB supposed to generate a new _id?
2. Because of the nature of problem 1, whenever I try to update the original document, it updates the upserted document instead since they have the same _id values even though their _ids are positioned at different document levels.
In conclusion, when given a 'home' document, how do I upsert correctly without adding a new record with the same values and _ids?
Thanks for your help!
EDIT
This is the JSON body content of the document with custom generated _id using crypto:
{
"_id": "1262d480eea83567181b3206",
"header": "hello",
"subheader": "hello"
}
Whereas, this is the body content of the upserted document.
{
"_id": {
"$oid": "1262d480eea83567181b3206"
},
"header": "helloasad",
"subheader": "helloasda"
}
As observed, after upserting, it takes the same _id value of the original document but on another document level.
A possible solution/explanation based on #Ashwanth Madhav information:
In your code 'id' was being sent to the update as a String type, but the id in MongoDB is an ObjectId type:
Code will be something like that:
var id;
if(req.params._id == 'undefined'){
// 'id' NEED TO BE AN ObjectId...
// 'id' WAS BEING SENT AS A 'String'
id = ObjectId(crypto.randomBytes(12).toString('hex'));
}
else {
id = ObjectId(req.params._id)
}
So I am currently working on a project with mongodb and nodejs and I was wondering, how can you update data in mongodb via nodejs? My problem is that I want to keep the old data and add new. For example, here is the data currently in my mongodb
{
"_id" : ObjectId("5a1c0c1c3b147ec2e31cceb3"),
"event_id" : "1",
"event_medium" : "null",
"event_tags" : ["#JustTesting"]
}
So I want to add new data to the event_tags array and still keep the old data.
So for example the end result would be this:
{
"_id" : ObjectId("5a1c0c1c3b147ec2e31cceb3"),
"event_id" : "1",
"event_medium" : "null",
"event_tags" : ["#JustTesting", "#Test", "#Something"]
}
You should use the update function of MongoDB for that. MongoDB knows different update operators, in your case you may use $push or $pushAll (the second is deprecated):
update one after the other with $push
YourCollection.update({ _id: 'xxx' }, { $push: { event_tags: '#Test' } });
YourCollection.update({ _id: 'xxx' }, { $push: { event_tags: '#Something' } });
or both at once with $pushAll (deprecated now)
YourCollection.update({ _id: 'xxx' }, { $pushAll: { event_tags: ['#Test', '#Something'] } });
To interact with MongoDB form your NodeJS app, I would use a library like this one.
Your starting point is the Update function in CRUD (Create,Read, Update, Delete) operations in Mongodb.
Your node program should have among others the update function where you set the _id field you want to update and load the content fields to be update in 'data' for example as below:
myModel.prototype.update = function (_id, data, callback) {
const query = { _id: this.mongo.ObjectId(_id) };
debug(' update:' + JSON.stringify(query));
this.mongo.collection('mycollection').update(query, data, callback);
};
This piece of code should be put in your Model, if you use MVC pattern.
There is a lot to go.
Honestly I recommend a more deep tutorial like parts 3 and 4 of this one for nodejs and Mongoose (mongo db driver):
MDN tutorial for mongo/node/express
I assume you are using mongoose..
eventModel.findOne({event_id:1 },
function(err, eventObj){
if(err){
//handle error
} else {
if(eventObj === null) {
//event doesnot exist
}
var tagList = eventObj.event_tags;
tagList.push('new_tag1');
tagList.push('new_tag2');
eventObj.event_tags = tagList;
eventObj.save(function(err){
if(err){
//handle error
} else {
//success
}
})
So I have a fairly simple piece of code as follows
db.get().collection('bars').insert({
barID: req.body.button,
}, {
$push: {
usersfbID: req.body.profileUser[0].facebookID
}
}, function(err, doc) {
if (err) {
throw err;
}
if (doc) {
console.log('Had to create a new document for this bar');
console.log(doc);
//callback(null, doc);
}
});
So, I'm just checking to see if a document for a bar exists, and if it doesn't then I create that document. And I want to insert an array for the usersfbID field so that I can store all the users going to the bar.
However, when I run the code, I don't get an error and it says the document has inserted but when the document logs, it doesn't have the userfbID field.
So what am I doing wrong? Does the $push operator only work with the update method of db? If so, how do I insert an array for that field?
Yes, it does work with the update methods
Reference > Operators > Update Operators > Array Update Operators > $push
Inserting a new entry means feeding the fields. In that case, there's no $push operation, since the array of the entry is freshly created and can be explicitly set (usersfbID:[req.body.profileUser[0].facebookID], meaning that you expect several fbId for that bar). Updating an array in an element of a collection isn't an insertion, it's an update.
So, just to provide an answer to the question I was facing..
Yes, you can only use $push or $addToSet with an update operation on a mongoDB document
Here is the way I implemented the code.
db.get().collection('bars').update({
barID: req.body.button,
}, {
$addToSet: {
usersfbID: req.body.profileUser[0].facebookID,
usersDocID: req.body.profileUser[0]._id
}
}, {
upsert: true
}, function(err, doc) {
if (err) {
console.log('There is an error here');
throw err;
}
if (doc) {
console.log('Had to create a new document for this bar');
callback(null, doc);
}
});
The upsert: true makes sure to insert a new document if the update method couldn't find the specified document.
Yet another first-timer problem here. This gets data from a database and displays it in some text fields (that part is not shown in the code below) and after the user edits it the data should be updated in the database via the findAndModify() method and I think this is where the issue lies. There are no errors, it just doesn't do anything. EDIT The following error is received: MongoError: Either an update or remove=true must be specified
server.js
MongoClient.connect("mongodb://user:secretPassword#aws-us-east-1-portal.7.dblayer.com:10712,aws-us-east-1-portal.10.dblayer.com:10316/database", function(err, db) {
if (err) throw err;
var contactList = db.collection("contactList");
app.put('/contactList/:id', function(req, res) {
var id = req.params.id;
console.log("edited: " + req.body.name); //works up until here
contactList.findAndModify({
query: {_id: mongojs.ObjectId(id)},
update: {$set: {name: req.body.name, email: req.body.email, number: req.body.number}},
new: true
}, function (err, doc) {
res.json(doc);
})
});
controller.js
$scope.update = function() {
$http.put('/contactList/' + $scope.contact._id, $scope.contact).success(function(response) {
refresh();
})
};
If this were me I would first do a couple of things:
Before your call to findAndModify just do a simple find using your query. Make sure you can actually find the object using your query. If that works you know that the 'find' part of the findAndModify is probably ok.
Do some console logging inside the callback handler of the findAndModify call. As it stands you do not do anything if an err is returned from the findAndModify call. It is possible your call is returning an error that you are just ignoring and it may provide some additional insight into your problem.
I would try these two first and see if it helps.
Update:
Example using native:
collection.findAndModify(
{ field: 'some value' },
[],
{ $set: { field2: 'some new value' } },
{ new:true },
function(err, doc) {
//handle err and doc
});
I'm trying to update an existing document by increment a counter and pushing an object to an array.
Here's the schema for User:
var UserSchema = new Schema({
[...]
posts: {
totalWords: { type: Number, min: 0, default: 0 },
_entries: [
{
words: { type: Number, min: 0 },
body: { type: String },
date: Date
}
]
},
});
And here's the update code:
var newPost = {
words: req.body.words,
body: req.body.entry,
date: new Date()
};
User.findOne(req.user._id, function (err, user) {
var previous = user.posts.totalWords;
user.posts.totalWords = previous + newPost.words;
user.posts._entries.push(newPost);
user.save(function (err) {
if (err) return res.send(400, err);
return res.json(newPost);
});
});
I get the following error:
[TypeError: Object.keys called on non-object]
Any ideas on how to solve this?
Answering my own question
I was able to solve the problem by changing:
User.findOne(req.user._id, function (err, user) { [...] });
Into this:
User.findById(req.user._id, function (err, user) { [...] });
I think, if you would like to use findOne you need follow syntax:
User.findOne({'_id': req.user._id}, {}, function (err, user) {
...
});
Not sure about findById() vs. findOne(), but I've had problems with Mongoose objects returning Object.keys called on non-object while saving or updating with mal-formed data or data corresponding to an older schema. While initializing the document, Mongoose was expecting a subdocument of some kind, but the data in the database didn't match that.
For me it usually happens when I change schemas from a simple object (String, Number, etc.) to a more complex subdocument of some kind. The schema types are mixed up and the object won't load, not even to fix the problem. I had to go into my database using the native driver, search for mal-formed documents using the $type operator, and update them individually.