Meteor observe on users cursor - meteor

I'm currently have pub/sub method for users like this:
Meteor.subscribe("userData");
Meteor.publish('userData', function () {
return Meteor.users.find({}, {fields: {profile: 1}});
});
And this works fine. But I have problems if I want to add few fields in profile in observe callbacks, like this:
Meteor.publish('userData', function () {
var self = this;
var users = Meteor.users.find({}, {fields: {profile: 1}});
var subHandle = users.observe({
added: function (fields) {
fields.profile.postCount = Post.find({'owner': fields._id}).count();
self.added("userData", fields._id, fields);
},
changed: function(newObj, oldObj){
fields.profile.postCount = Post.find({'owner': fields._id}).count();
self.changed("userData", newObj._id, newObj);
},
removed: function(obj) {
self.removed("userData", obj._id);
}
});
self.ready();
self.onStop(function () {
subHandle.stop();
});
});
Problem is that when I try to find users on client side, I can find only one user, myself if I'm logged in (Meteor.users.find().fetch() inside console). And I saw that publication is finished (Network WS section inside console), so I know that more than one users is pushed to client side.
So I obviously doing something wrong, can someone point me to the right direction?

There may be more than one issue here, but what catches my eye is the fact that you are using the publication's name in your added/changed/removed callbacks instead of the collection name ('users'). Try modifying your observe as follows:
var subHandle = users.observe({
added: function (fields) {
fields.profile.postCount = Post.find({'owner': fields._id}).count();
self.added('users', fields._id, fields);
},
changed: function(newObj, oldObj){
fields.profile.postCount = Post.find({'owner': fields._id}).count();
self.changed('users', newObj._id, newObj);
},
removed: function(obj) {
self.removed('users', obj._id);
}
});
If that doesn't work, let me know and I'll examine it further.

Related

Client data not being updated in Meteor application

I have a Meteor application with a publish of:
Meteor.publish('my_items', function() {
var selector = {owner_id: this.userId};
var items = ItemOwnership.find(selector, {fields: {item_id: 1}}).fetch();
var itemIds = _.pluck(items, 'item_id');
return Items.find({
_id: {$in: itemIds},
item_archived_ts: { $exists: false }
});
});
and a subscription of this:
Meteor.subscribe('my_items');
The application allows for the user to add items to the 'Items' collection and this is done by calling a server method. The Items collection on the server is updated with the new record, but the client-side equivalent collection is not showing the new record. Is there anything obviously wrong with what I am doing, or some way to debug this?
p.s. there are no client/server-side errors occurring?
I found a way to accomplish this using the reywood:publish-composite Meteor package. Here is the publish that achieves this:
Meteor.publishComposite('my_items', {
find: function () {
var selector = {owner_id: this.userId};
return ItemOwnership.find(selector, {fields: {item_id: 1}});
},
children: [
{
find: function(IOrecord){
return Items.find({
_id: IOrecord.item_id,
item_archived_ts: { $exists: false }
});
}
}
]
});

iron router syntax: onAfterAction

Router.route('/courses/:_catalog', function () {
var courseCatalog = this.params._catalog.toUpperCase();
Meteor.subscribe("courseCatalog", courseCatalog);
this.render('CourseDetail', {
to: 'content',
data: function () {
return Courses.findOne({catalog: courseCatalog});
}
});
}, {
onAfterAction: function() {
if (!Meteor.isClient) {
return;
}
debugger
var course = this.data(); <======
SEO.set({
title: "course.catalog"
});
}
});
In the above code, please look at the debugger statement. I want to access the data but it seems I am doing something wrong because this.data doesn't exist. I also tried Courses.find().fetch() but I only get an empty array inside onAfterAction. What's the right syntax and what am I missing?
It needs to be inside a this.ready() block:
onAfterAction: function() {
if (this.ready()) {
var course = this.data();
...
}
}
You need to subscribe to data first. Have a look at the waitOn function to do this. The server only sends the documents you subscribed to, and since you didn't subscribe, Courses.find().fetch() returns an empty array.
Also, don't put SEO stuff in onAfterAction. Put it in onRun which is guaranteed to only run once.

Why is data set with Meteor Iron Router not available in the template rendered callback?

This is a bit puzzling to me. I set data in the router (which I'm using very simply intentionally at this stage of my project), as follows :
Router.route('/groups/:_id',function() {
this.render('groupPage', {
data : function() {
return Groups.findOne({_id : this.params._id});
}
}, { sort : {time: -1} } );
});
The data you would expect, is now available in the template helpers, but if I have a look at 'this' in the rendered function its null
Template.groupPage.rendered = function() {
console.log(this);
};
I'd love to understand why (presuming its an expected result), or If its something I'm doing / not doing that causes this?
From my experience, this isn't uncommon. Below is how I handle it in my routes.
From what I understand, the template gets rendered client-side while the client is subscribing, so the null is actually what data is available.
Once the client recieves data from the subscription (server), it is added to the collection which causes the template to re-render.
Below is the pattern I use for routes. Notice the if(!this.ready()) return;
which handles the no data situation.
Router.route('landing', {
path: '/b/:b/:brandId/:template',
onAfterAction: function() {
if (this.title) document.title = this.title;
},
data: function() {
if(!this.ready()) return;
var brand = Brands.findOne(this.params.brandId);
if (!brand) return false;
this.title = brand.title;
return brand;
},
waitOn: function() {
return [
Meteor.subscribe('landingPageByBrandId', this.params.brandId),
Meteor.subscribe('myProfile'), // For verification
];
},
});
Issue
I was experiencing this myself today. I believe that there is a race condition between the Template.rendered callback and the iron router data function. I have since raised a question as an IronRouter issue on github to deal with the core issue.
In the meantime, workarounds:
Option 1: Wrap your code in a window.setTimeout()
Template.groupPage.rendered = function() {
var data_context = this.data;
window.setTimeout(function() {
console.log(data_context);
}, 100);
};
Option 2: Wrap your code in a this.autorun()
Template.groupPage.rendered = function() {
var data_context = this.data;
this.autorun(function() {
console.log(data_context);
});
};
Note: in this option, the function will run every time that the template's data context changes! The autorun will be destroyed along with the template though, unlike Tracker.autorun calls.

Subscription manager doesn't update collection after new subscription

In my Meteor application I have this situation in which I have a 'Settings' collection only on the client. So the publish function is:
Meteor.publish('settings', function (option) {
this.added("settings", "settings", {
bar: true,
foo: { .... }
});
this.ready();
});
Initially I subscribe like:
waintOn: function () {
return subs.subscribe('settings')
}
But when the route changes I subscribe again like
return subs.subscribe('settings', 10);
After this I see that the publish function runs, but on the client nothing happens.
For some reason the server thinks that the data did not change and decides to do nothing. So the question is how can I tell Meteor that the data has changed so it sends the data to the client. If the problem is completely different, I'm also very interested!!
UPDATE: the publish function might look like this:
Meteor.publish('settings', function (option) {
var list;
if (option === 10) {
list = [1,2,3,4,5];
}
this.added("settings", "settings", {
bar: true,
foo: list
});
this.ready();
});
UPDATE2: Expected solution:
var isNew = true;
Meteor.publish('settings', function () {
if(isNew) {
this.added("settings", "settings", {
bar: true,
foo: list
});
isNew = false;
}
else {
this.changed('settings', 'settings', {.....});
}
this.ready();
});
It would even be better if there was a function like this.exists('settings', 'settings') because the isNew variable feels a bit like a hack!
Anyway, I have it working now as follows:
try {
this.removed('settings', 'settings');
} catch(e){}
this.added('settings', 'settings', {...});
...

How do I make a collection reactive based on the contents of another?

In short, I want to do:
Meteor.publish('items', function(){
return Item.find({categoryId: Categories.find({active: true} });
});
The flag 'active' as part of 'Categories' changes regularly.
I also tried unsub/resub to the Items collection by leveraging reactivity on the Categories collections, and it works, unfortunately it re-triggers on ANY modification to the Categories collection, regardless if it affected the 'active' flag or not.
What are my options?
Nothing solved the issue of the items not being 'deleted' locally when the category is flagged as inactive on the server. Solution (ish) is to:
Client:
Categories.find({active: true}).observeChanges({
added: function(){
itemsHandle && itemsHandle.stop();
itemsHandle = Meteor.subscribe("items");
}
});
Server:
Meteor.publish('items', function(){
var category = Categories.findOne({active: true});
return category && Items.find({categoryId: Categories.findOne({active: true}._id);
});
I realize this isn't perfect (still uses client side code), but it works and its the cleanest I could think of. I hope it helps someone!
A possible solution is to create a dependency object, watch for all categories change, and trigger the dep change if the active flag was toggled. Something along these lines:
var activeCount = Categories.find({active: true}).count();
var activeDep = new Deps.Dependency();
Deps.autorun(function() {
var activeCountNow = Categories.find({active: true}).count();
if(activeCountNow !== activeCount) {
activeCount = activeCountNow;
activeDep.changed();
}
});
Meteor.publish('items', function(){
activeDep.depend();
return Item.find({categoryId: Categories.find({active: true} });
});
Note: I'm only verifying whether the number of active categories have changes so that I don't have to keep the active list in the memory. This may or may not be appropriate depending on how your app works.
Edit: Two-sided flavor mentioned in the comments:
Client:
var activeCount = Categories.find({active: true}).count();
var activeDep = new Deps.Dependency();
Deps.autorun(function() {
var activeCountNow = Categories.find({active: true}).count();
if(activeCountNow !== activeCount) {
activeCount = activeCountNow;
activeDep.changed();
}
});
Deps.autorun(function(){
activeDep.depend();
Meteor.subscribe('items', new Date().getTime());
});
Server:
Meteor.publish('items', function(timestamp) {
var t = timestamp;
return Item.find({categoryId: Categories.find({active: true} });
});
Meteor.startup(function() {
Categories.find().observe({
addedAt: function(doc) {
trigger();
},
changedAt: function(doc, oldDoc) {
if(doc.active != oldDoc.active) {
trigger();
}
},
removedAt: function(oldDoc) {
trigger();
}
});
});
Now, the trigger function should cause the publish to rerun. This time it's easy when it's on the client (change subscription param). I'm not sure how to do this on the server - perhaps run publish again.
I use the following publish to solve a similar issue. I think it is only the one line nesting of queries that limits the reactivity. Breaking one query out inside the publish function seems to avoid the issue.
//on server
Meteor.publish( "articles", function(){
var self= this;
var subscriptions = [];
var observer = Feeds.find({ subscribers: self.userId }, {_id: 1}).observeChanges({
added: function (id){
subscriptions.push(id);
},
removed: function (id){
subscriptions.splice( subscriptions.indexOf(id)) , 1);
}
});
self.onStop( function() {
observer.stop();
});
var visibleFields = {_id: 1, title: 1, source: 1, date: 1, summary: 1, link: 1};
return Articles.find({ feed_id: {$in: subscriptions} }, { sort: {date: -1}, limit: articlePubLimit, fields: visibleFields } );
});
//on client anywhere
Meteor.subscribe( "articles" );
Here is another SO example which gets the search criteria from the client through subscribe if you decide that is acceptable.
Update: Since the OP struggled to get this going I made a gist and launched a working version on meteor.com. If you just need the publish function it is as above.

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