Updating a record and then displaying it in iron router function - mongodb

I've got the following iron-router setup with meteor:
Router.map(function() {
this.route('decoded', {
path: '/id/:id',
data: function() {
message.update({_id: this.params.id._id}, {$set: {read: "1"}});
return message.findOne({id: this.params.id});
}
});
Take note that I am storing an id, which is not the same as _id that mongodb generates.
In my template I have {{subject}}
On insert, the value of read is 0, when they visit the url /id/:id I want the value of read to be changed to 1, and then display the subject.
When I run it, I don't get any errors or anything. It displays my message, just fine, but doesn't update the read field.

Related

Meteor: Increment DB value server side when client views page

I'm trying to do something seemingly simple, update a views counter in MongoDB every time the value is fetched.
For example I've tried it with this method.
Meteor.methods({
'messages.get'(messageId) {
check(messageId, String);
if (Meteor.isServer) {
var message = Messages.findOne(
{_id: messageId}
);
var views = message.views;
// Increment views value
Messages.update(
messageId,
{ $set: { views: views++ }}
);
}
return Messages.findOne(
{_id: messageId}
);
},
});
But I can't get it to work the way I intend. For example the if(Meteor.isServer) code is useless because it's not actually executed on the server.
Also the value doesn't seem to be available after findOne is called, so it's likely async but findOne has no callback feature.
I don't want clients to control this part, which is why I'm trying to do it server side, but it needs to execute everytime the client fetches the value. Which sounds hard since the client has subscribed to the data already.
Edit: This is the updated method after reading the answers here.
'messages.get'(messageId) {
check(messageId, String);
Messages.update(
messageId,
{ $inc: { views: 1 }}
);
return Messages.findOne(
{_id: messageId}
);
},
For example the if(Meteor.isServer) code is useless because it's not
actually executed on the server.
Meteor methods are always executed on the server. You can call them from the client (with callback) but the execution happens server side.
Also the value doesn't seem to be available after findOne is called,
so it's likely async but findOne has no callback feature.
You don't need to call it twice. See the code below:
Meteor.methods({
'messages.get'(messageId) {
check(messageId, String);
var message = Messages.findOne({_id:messageId});
if (message) {
// Increment views value on current doc
message.views++;
// Update by current doc
Messages.update(messageId,{ $set: { views: message.views }});
}
// return current doc or null if not found
return message;
},
});
You can call that by your client like:
Meteor.call('messages.get', 'myMessageId01234', function(err, res) {
if (err || !res) {
// handle err, if res is empty, there is no message found
}
console.log(res); // your message
});
Two additions here:
You may split messages and views into separate collections for sake of scalability and encapsulation of data. If your publication method does not restrict to public fields, then the client, who asks for messages also receives the view count. This may work for now but may violate on a larger scale some (future upcoming) access rules.
views++ means:
Use the current value of views, i.e. build the modifier with the current (unmodified) value.
Increment the value of views, which is no longer useful in your case because you do not use that variable for anything else.
Avoid these increment operator if you are not clear how they exactly work.
Why not just using a mongo $inc operator that could avoid having to retrieve the previous value?

Can't find user by name with Monk / Mongo

I'm working on a CRUD application with Node, Mongo & Monk.
I'd like to find a record by username, and then update it.
But I'm unable to find a record, this code isn't working:
// GET User Profile
router.get('/userprofile', function(request,response){
var db = request.db;
var userName = request.body.username;
var collection = db.get('usercollection');
collection.findOne({
"username": userName
},{},function(e,user){
response.render('userprofile', {
"user": user
});
});
});
The "findOne" method doesn't return anything, and the "user" object ends up empty.
Remove the middle empty object from the signature for the findOne() method signature for the query to work:
Note: The way you are getting the userName is for when the request method is a POST, here you are doing a GET so you need to use the request.query property. More details here
var userName = request.query.username;
collection.findOne({"username": userName}, function(e,user){
response.render('userprofile', { "user": user });
});
If you want to update then you can use the update() method, suppose you want to update the username field to change it to 'foo', the following stub shows how you can do the update:
var u = collection.update({ "username": userName }, { "$set": { username: 'foo' } });
u.complete(function (err, result) {
console.log(err); // should be null
console.log(result); // logs the write result
});
Ok, I found out the problem.
Chridam's code was correct, but I also needed to change my form from a GET to a POST. Once I did that, the form POSTed and mongo could see request.body.username (it was null before) and look up my user using Chridam's code.
After reading Chridam's revised answer, was also able to get it to work with GET.
Now working on the update code..

How to show data from mongoDB with ObjectID

i have an "back end" application which write in MongoDb (in database i have _id: with ObjectId("13f6ea...002")) i use meteor app to show information. Everything was good i displays list of information with {{#each}}. But when i wanted show one element with '_Id' nothing works.
I read this issue and adapt my code to get right root, But i can't display anything on the page. I tried to write Template helpers but it didn't helped
Db record:
{
_id: ObjectId("13f6ea...002"),
url: "foo",
title: "bar",
published: "2014-08-22 03:26:21 UTC",
image: "foo.jpg",
summary: "foo ",
categories: [
"F",
"B"
],
...
}
Route:
this.route('news', {
path: '/news/:_id',
template: 'news',
waitOn: function () {
var id = this._id;
Meteor.subscribe('news', id);
},
data: function() {
var id = this.params._id;
return News.findOne({ _id: Meteor.Collection.ObjectID(this.params._id)});
},
action : function () {this.render();},
});
Publish
Meteor.publish('news', function(id) {
return News.find({_id: id});
});
Template which redirect to unique post
<h4>{{title}}</h4>
And template is just {{news}}
How can i fix this?
UPDATE
My solutions to fix that:
router.js
waitOn: function () {
var id = this._id;
Meteor.subscribe('News', id);
},
data: function() {
return News.findOne(new Meteor.Collection.ObjectID(this.params._id));
},
and in template
<a href="news/{{_id._str}}">
Navigate to the appropriate url in your browser (i.e. localhost:3000/news/[_id]), open the console and enter:
Router.current().data()
That will show you the data context of the current route. Either it returns nothing, in which case there is a fundamental problem with your News.findOne query as it's returning nothing, or (more likely) it returns the required document.
In the latter case, as far as I can see there is no news property within that document, which is why it isn't rendering anything. If you change {{news}} to {{url}} or {{summary}} I would imagine it would render the requested property.
If by {{news}} you're trying to render the entire document, then (aside from the fact that it will render as something like [Object]) you need to make news a property of the object returned by your data function:
return {
news: News.findOne({ _id: Meteor.Collection.ObjectID(this.params._id)});
};
Getting Document with _id :
In the .js file under events, Say on click event and Collection EventList :-
'Submit form' : function () {
var id = this._id;
return EventList.find({_id : id}).fetch();
}
This would return the object for the id. In my Case, I am displaying a field for all documents in Collection. User selects a record and clicks Submit, which fetches all Document fields and displays to the User

Meteor returning a field from MongoDB works in console but not in application

I am trying to read out a file in my MongoDB database. In the console the response is correct while in my application I get the following error:
Uncaught TypeError: Cannot read property 'iati' of undefined
I defined a template helper which should return a certain sub-field within my MongoDB collection. However the following does not seem to work (I get the beforementioned error).
Template.hello.helpers({
test: function() {
return Test.findOne().iati;
}
});
What does seem to work is to return the entire object:
Template.hello.helpers({
test: function() {
return Test.findOne();
}
});
And then call the specific field within the template:
{{test.iati}}
However, I want to use the data within the JavaScript script. What am I doing wrong?
Collection methods like Tests.findOne() return the documents that are already fetched to the client's Minimongo copy. Before your document is fetched, findOne() will return null.
To safeguard against this, simply check the result in the helper before you proceed with the calculation:
Template.hello.helpers({
test: function() {
if(! Test.findOne()) return;
return Test.findOne().iati;
},
});
You can also wait for the subscription in the Iron Router to ensure the proper documents are loaded:
this.route('routeName', {
...
onBeforeAction: function() {
this.subscribe('subscriptionName').wait();
...
},
...
});

Mongoose No matching document found using id() method. Error caused by asynchronous delete requests

Making asynchronous requests in a loop to delete documents from an embedded collection:
_.each deletedItem, (item) ->
item.$delete()
Erratically throws this error:
{ message: 'No matching document found.', name: 'VersionError' }
When executing:
var resume = account.resumes.id(id);
resume.remove();
account.save(function (err, acct) {
console.log(err);
if(err) return next(err);
res.send(resume);
});
After logging account.resumes and looking through the _id's of all of the resumes, the document I am attempting to find by id, exists in the collection.
530e57a7503d421eb8daca65
FIND:
{ title: 'gggff', _id: 530e57a7503d421eb8daca65 }
IN:
[{ title: 'asddas', _id: 530e57a7503d421eb8daca61 }
{ title: 'gggff', _id: 530e57a7503d421eb8daca65 }
{ title: 'ewrs', _id: 530e57a7503d421eb8daca64 }]
I assume this has to do with the fact that I am performing these requests asynchronously, or that there is a versioning issue, but I have no idea how to resolve it.
It doesn't make any sense to me how when I log the resumes, I can see the resume I attempt to find, yet if I log:
log(account.resumes.id(id));
I get undefined.
UPDATE
I've discovered that my issue is with versioning.
http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html
But I am still unsure how to resolve it without disabling versioning, which I don't want to do.
In mongodb version 3, documents now have an increment() method which manually forces incrementation of the document version. This is also used internally whenever an operation on an array potentially alters array element position. These operations are:
$pull $pullAll $pop $set of an entire array
changing the version key
The version key is customizable by passing the versionKey option to the Schema constructor:
new Schema({ .. }, { versionKey: 'myVersionKey' });
Or by setting the option directly:
schema.set('versionKey', 'myVersionKey');
disabling
If you don’t want to use versioning in your schema you can disable it by passing false for the versionKey option.
schema.set('versionKey', false);
MongooseJs API docs explicitly warn on disabling versioning, and recommend against it. Your issue is due to workflow. If you're updating your collection from the UI, sending the API request and not refreshing your object with the object from the backend -- then attempt to update it again, you'll encounter the error you are reporting. I suggest either consuming/updating the object scope from the API response, then __v is correctly incremented. Or don't send the __v field on the PUT API request, this way it won't conflict with version on the collection in the database.
Another option is -- when requesting the object from the backend, have the API response not send the __v field, this way you don't have to code logic to NOT send it from the frontend. On all your gets for that collection, do either one of the following (depends how you write your queries):
var model = require('model');
var qry = model.find();
qry.select('-__v');
qry.exec(function(err,results){
if(err) res.status(500).send(err);
if(results) res.status(200).json(results);
});
OR
var model = require('model');
model.find({}, '-__v', function(err,results){
if(err) res.status(500).send(err);
if(results) res.status(200).json(results);
});