I have a code that looks like this
Trades.find().observeChanges({
changed: function(id, fields) {
// do stuff
}
});
Where each Trades has an array of items inside
TradesSchema = new SimpleSchema({
// ...
items: {
type: [String]
},
// ...
});
Trades.attachSchema(TradesSchema);
These items are being changed sometimes, and I want to track the changes. The code works fine, except that in fields it returns all the items, not only the items that were changed.
Is there any way to see which exactly item was changed without changing the structure of the collection?
Thanks #Season for the hint!
observeChanges only gives the new values, so you have to use observe, since it returns both the new and old documents. Then you need to compare them to see what exactly got changed. (See docs for observe on meteor.com)
Trades.find().observe({
changed: function(newDocument, oldDocument) {
// compare newDocument to oldDocument to find out what has changed
}
});
Related
I am completely new to the fields of Mongoose and MongoDB.
I am currently trying trying to remove one element from my database.
This is my code so far:
My issueModel:
var mongoose = require('mongoose'); // loading module for mongoose
var db = mongoose.connect('mongodb://localhost/issuedb');
var issueSchema = new mongoose.Schema({
title: String,
description: String,
priority: String,
status: String
});
// Constructor Function:
var issueModel = mongoose.model('issues', issueSchema); // have to give the
name of the collection where the element should be stored + Schema
// Export this Construction Function for this Module:
module.exports = issueModel; // careful: module != model !
My post method for using the delete method:
// creating the router for deleting one item:
router.post('/delete/:id', (req, res) => {
console.log(req.params.id);
issueModel.remove({id: req.params.ObjectId})
.setOptions({ single: true }).exec(function (err, deleted) {})
.then(issues => res.render('issue', {issues: issues}));
The thing i would like to do here is using the object id - which is correctly stored in req.params.ObjectID according to my console.log, and deleting the corresponding object.
But currently , when i have got a table with about 3-4 entries, always the first one gets deleted. Why is that? I am really TOTALLY new and really tried searching a lot, but i could not find any solution until now. I am happy about any tips that would help me.
What am i doing wrong?
The ID in the URL and the Object.ID are the same! Why is the first object deleted then, not the second or the third?
I am hopeless right now.
I also read about the remove() option not being really used in todays time. But we were told at university to use this method right now.
I also tried findOneByID and delete methods i found in the mongoose database.
If you need any more code please let me know!
You can use one of the convenience methods for this: findByIdAndRemove:
issueModel.findByIdAndRemove(req.params.ObjectId, function(err) {
if (err) { ... failed }
});
This will remove a whole document matching the ID which I think its what you want, if you want to a remove property from a document that's a different query.
If you don't use one of the convenience methods which just take IDs (have ById in them), then you have to convert your ID from a string to an ObjectId:
const { ObjectId } = require('mongodb');
issueModel.remove({ id: ObjectId(req.params.ObjectId) }).setOptions({ single: true })
I have MemberProfiles and MemberPayments collections.The MemberProfile has expiryDate field which is set to current date at insert.I need to extend expirDate of a unique MemberProfile whenever a MemberPayment is added to that MemberProfile.
MemberProfiles = new Mongo.Collection('memberProfiles');
MemberProfileSchema = new SimpleSchema({
expiryDate: {
type: Date,
autoValue: function () {
return moment().toDate();
},
autoform: {
type: "hidden"
}
}
// to insert into Memb erProfiles
{{> quickForm collection="MemberProfiles" id="insertMemberProfileForm" type="insert" class="new-recipe-form"}}
//the code for MemberPayments collection
MemberPayments = new Mongo.Collection('memberPayments');
MemberPayments.before.insert(function (userId, doc) {
let memberProfile= MemberProfiles.direct.findOne({profile: doc.memberId});
MemberProfiles.update(doc.memberId, {
$set: {
expiryDate: moment().add(31, 'days');
,
}
}
)
});
I have added all the necessary packages but still this doesnt work.I am getting error Cannot set property 'expiryDate' of undefined
It is challenging to try and resolve issues like this without having a more complete example of the app or reference to the complete project in github or somewhere else.
However, when I read through your code I noticed an issue in your MemberProfiles.update() function. I also noticed that it appears you are only processing your form from the client side (e.g. because your quickform is not using a Meteor Method) so you will have to manually call the SimpleSchema .clean() method to generate your autovalue. Keep in mind that your client side approach might work ok now, but once you remove the insecure package you will either have to implement a Meteor Method to perform the insert or configure your collection allow/deny rules to allow client side insert (this is dangerous).
Since you are using moment.js you need to be careful that you always pull the date from the moment object before storing in mongodb. In this case, you are trying to set expiryDate to the value returned from moment().add(31, 'days') which is just another moment object.
Also, I would assume you want to add 31 days to the current value of expiryDate, however you are never initializing moment with the expiryDate. Therefore, you will always be setting the expiryDate to 31 days from the time the function executes.
Lastly, you have a syntax error (; inside your $set object) and your findOne selector includes {profile: doc.memberId} however your MemberProfiles schema says there is only a _id and expiryDate field in your collection.
Try this new logic that addresses the above issues and see if that resolves your issue.
MemberPayments.before.insert(function (userId, doc) {
let memberProfile = MemberProfiles.direct.findOne({profile: doc.memberId});
if (memberProfile) {
if (!memberProfile.expiryDate) {
console.log("expiryDate was not previously set!");
} else {
MemberProfiles.update({profile: doc.memberId}, {
$set: {
expiryDate: moment(memberProfile.expiryDate).add(31, 'days').toDate()
}
});
}
} else {
console.log("memberProfile not found");
}
});
Now that this is fixed, you need to resolve the issue of your autovalue not being generated on the client side. You do this by calling the SimpleSchema .clean() method. Since you are not using Meteor Methods to process your quickForm (and therefore doing everything client side), you need to add the below AutoForm hook to ensure that the SimpleSchema .clean() method is called before the doc is saved (which will then execute your autovalue logic).
AutoForm.hooks({
insertMemberProfileForm: {
before: {
insert: function(doc) {
MemberProfileSchema.simpleSchema().clean(doc);
return doc;
}
}
}
});
You should put the above code in the onRendered() callback of the template that creates your quickform (e.g. the template that contains the below code in the HTML).
{{> quickForm collection="MemberProfiles" id="insertMemberProfileForm" type="insert" class="new-recipe-form"}}
I would like if is possible to update a field of all documents in a collection with a reference to another document. I have tried to do this with the code below:
var project = db.Project.find({slug:"engine"});
db.Activity.update({}, {$set:{'project':DBRef("Project", project._id, "mydb")}});
When I look at the Activity documents, in the "project" field, the result is:
{
_id: ObjectId("..."),
"project": DBRef("Project", undefined, "mydb")
}
Is there a way to do this correctly?
Thanks in advance.
Seems to me you're having a promise callback problem. You can solve it in two ways:
Option one: Put the function depending of your data return inside a callback of the first function, for example:
db.Project.find({slug:"engine"}, function(error, data) {
db.activity.update(...data.Id...);
});
Option two: Wait for the return of the find to be completed:
var project = db.Project.find({slug:"engine"});
project.then(function(error,data) {
db.activity.update(...project.Id...);
});
Both should work. The problem is that when you make the first call, it returns a promise, not the value itself. If you are making confusion on this topic, you can take a look at:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise
Hope my answer helped you.
// in server.js
Meteor.publish("directory", function () {
return Meteor.users.find({}, {fields: {emails: 1, profile: 1}});
});
// in client.js
Meteor.subscribe("directory");
I want to now get the directory listings queried from the client like directory.findOne() from the browser's console. //Testing purposes
Doing directory=Meteor.subscribe('directory')/directory=Meteor.Collection('directory') and performing directory.findOne() doesn't work but when I do directory=new Meteor.Collection('directory') it works and returns undefined and I bet it CREATES a mongo collection on the server which I don't like because USER collection already exists and it points to a new Collection rather than the USER collection.
NOTE: I don't wanna mess with how Meteor.users collection handles its function... I just want to retrieve some specific data from it using a different handle that will only return the specified fields and not to override its default function...
Ex:
Meteor.users.findOne() // will return the currentLoggedIn users data
directory.findOne() // will return different fields taken from Meteor.users collection.
If you want this setup to work, you need to do the following:
Meteor.publish('thisNameDoesNotMatter', function () {
var self = this;
var handle = Meteor.users.find({}, {
fields: {emails: 1, profile: 1}
}).observeChanges({
added: function (id, fields) {
self.added('thisNameMatters', id, fields);
},
changed: function (id, fields) {
self.changed('thisNameMatters', id, fields);
},
removed: function (id) {
self.removed('thisNameMatters', id);
}
});
self.ready();
self.onStop(function () {
handle.stop();
});
});
No on the client side you need to define a client-side-only collection:
directories = new Meteor.Collection('thisNameMatters');
and subscribe to the corresponding data set:
Meteor.subscribe('thisNameDoesNotMatter');
This should work now. Let me know if you think this explanation is not clear enough.
EDIT
Here, the self.added/changed/removed methods act more or less as an event dispatcher. Briefly speaking they give instructions to every client who called
Meteor.subscribe('thisNameDoesNotMatter');
about the updates that should be applied on the client's collection named thisNameMatters assuming that this collection exists. The name - passed as the first parameter - can be chosen almost arbitrarily, but if there's no corresponding collection on the client side all the updates will be ignored. Note that this collection can be client-side-only, so it does not necessarily have to correspond to a "real" collection in your database.
Returning a cursor from your publish method it's only a shortcut for the above code, with the only difference that the name of an actual collection is used instead of our theNameMatters. This mechanism actually allows you to create as many "mirrors" of your datasets as you wish. In some situations this might be quite useful. The only problem is that these "collections" will be read-only (which totally make sense BTW) because if they're not defined on the server the corresponding `insert/update/remove' methods do not exist.
The collection is called Meteor.users and there is no need to declare a new one on neither the server nor the client.
Your publish/subscribe code is correct:
// in server.js
Meteor.publish("directory", function () {
return Meteor.users.find({}, {fields: {emails: 1, profile: 1}});
});
// in client.js
Meteor.subscribe("directory");
To access documents in the users collection that have been published by the server you need to do something like this:
var usersArray = Meteor.users.find().fetch();
or
var oneUser = Meteor.users.findOne();
I know this is a nood question, but I'm trying to work out how to update a value in a document from a route in iron router. I've found the spot I need to put the function, but I'm struggling with the mongo code needed to make it work.
I'm trying to increment a views element each time a link is clicked, so have added the following code to the route.
data: function () {
var project = projectDocs.findOne(this.params._id);
// need to increment views value by one
console.log(project.views);
projectDocs.update({id: project.id},
{$inc: {views: 1}}
);
console.log(project.views);
return project;
}
});
The project.views value is returning the correct value, but the code to update the value throws an exception at the moment.
I tried the simple thing of project.views++ which increments the variable within the function but it never gets pushed to the database (no surprises there I guess).
Can someone point me in the direction I need to get this value to inc (and is this even the right place to do this?).
Thanks.
Peter.
OK, I found this link that has lead me part of the way http://books.google.com.au/books?id=uGUKiNkKRJ0C&pg=PA37&lpg=PA37&dq=Cannot+apply+$inc+modifier+to+non-number&source=bl&ots=h7qyOddRsf&sig=EWFw9kNLGHoFEUS-nTNsBStDRcQ&hl=en&sa=X&ei=cRGXUse0DNGciAfk6YHgCA&ved=0CFcQ6AEwBQ#v=onepage&q=Cannot%20apply%20%24inc%20modifier%20to%20non-number&f=false which explains that you can only inc numeric values (I had this as a string it seems.
Now the problem is that I seem to be in an endless loop.
The function now looks like
this.route('projectPage', {
path: '/projects/:_id',
waitOn: function() {
return Meteor.subscribe('singleProject', this.params._id);
},
data: function () {
var project = projectDocs.findOne(this.params._id);
// need to increment views value by one
console.log("Views", project.views);
console.log("Project", project);
projectDocs.update(project._id,
{$inc: {views: 1}}
);
console.log(project.views);
return project;
}
});
Why would this be looping?
Use _id instead of id. So
projectDocs.update({_id: project._id},
{$inc: {views: 1}}
);
If that's not it, perhaps you could update your answer with whatever exception you are getting.
Just read the fantastic new documentation on iron-router a bit further and moved the $inc function to the unload hook and all seems to be good.
this.route('projectPage', {
path: '/projects/:_id',
waitOn: function() {
return Meteor.subscribe('singleProject', this.params._id);
},
data: function () {
return projectDocs.findOne(this.params._id);
},
unload: function() {
var project = projectDocs.findOne(this.params._id);
// need to increment views value by one
projectDocs.update(project._id,
{$inc: {views: 1}}
);
}
// could possibly use layout: popup_layout? here
});
Would love some confirmation that this is actually where I should be doing this (and it does seem a bit inefficient to be doing so many "findOne"'s) but its working for the moment.