I am doing a find on a collection of nodes and am then storing the info in a variable.
I am then console.logging this data to see the contents of it. The thing is, my data stays an empty array for a split second and then a new console.log is done with an array of data. See my code below:
Template.temperature.helpers({
node() {
let node = Nodes.find({_id:Session.get('selectedNode')});
console.log(node);
return '';
}
});
My console output:
1: []
2: [Object]
What could be the reason for this?
In your router, subscribe within waitOn:
Router.route('/home', {
waitOn: function() {
return [
Meteor.subscribe('nodes'),
];
},
action: function() {
if (this.ready()) {
this.render();
}
},
});
This will ensure that the route will wait until the subscription is completed before executing the route. It uses the meteor loading hook, so the wait will utilize whatever loading screen or animation you ahve setup.
Related
I'm using Iron Router. I have a RouterController that looks something like this:
var loggedInUserController = RouteController.extend({
layoutTemplate: "GenericLayout",
waitOn: function () {
return Meteor.subscribe("TheDataINeed");
}
});
And I have a route defined which uses this controller to wait for the 'TheDataINeed':
Router.route("/myapp", {
name: "Landing",
controller: loggedInUserController,
data: function () {
if(this.ready()){
return {content: "page-landing"};
}
}
});
Now, the problem is the data I am subscribed to is conditional: meaning, depending on the user's role, I publish different data, like so:
if (!Roles.userIsInRole(this.userId, 'subscribed') ) {
return [
myData.getElements({}, { fields: { _id: 1, title: 1}, limit: 5 })
];
} else {
return [
myData.getElements({}, { fields: { _id: 1, title: 1} })
];
}
When the user's role is not 'subscribed', I limit the published data to 5 elements.
The problem is publishing is not reactive, so when the user changes his role for the first time to 'subscribed' and I navigate to my route ("/myapp"), the user still sees the limited number of elements instead of all of them.
Is there a way to manually re-trigger the subscription when I am loading this route? If possible, I'd like to do this without adding new packages to my app.
Not sure about that approach but can you try to set session value in route instead of subscription code. Then in a file on client side where your subscriptions are you can wrap Meteor.subscribe("TheDataINeed") in Tracker.autorun and have a session as a subscription parameter. Every time that session value is changed autorun will rerun subscription and it will return you data based on a new value.
I'm defining a route that will show an appointment for a patient. I would like the template to show both the patient information and the appointment information.
I have this published:
Meteor.publish('userAppointment', function(appointmentId){
check(appointmentId, String);
var userId = Appointments.findOne(appointmentId).patientId;
return [
Appointments.find({_id: appointmentId}),
Meteor.users.find({_id: userId}, {fields: {profile: true, emails: true}})
];
});
Unfortunately Iron Router doesn't seem to be successfully waiting on the data subscription to complete before it tries to set the data context.
Note where I put debugger:
Router.route('/admin/appointment/:id', {
name: 'AppointmentShow',
waitOn: function(){
return [
Meteor.subscribe("userAppointment", this.params.id)
]
},
data: function(){
var appointmentId = this.params.id;
debugger
var patientId = Appointments.findOne(appointmentId).patientId;
return {
appointment: Appointments.findOne(appointmentId),
patient: Meteor.users.findOne(patientId)
}
}
});
At the time when debugger stops the code, when I do Meteor.users.find().fetch() and Appointments.find().fetch() in the console only the currently logged-in user (me) is available and there are no appointments available.
I expect to see two users (me and the patient) and one appointment available because that's the data that should be available after the waitOn has finished subscribing.
Am I missing something here?
EDIT----- Still doesn't make sense to me ------
When I change my route to this:
Router.route('/admin/appointment/:id', {
name: 'AppointmentShow',
waitOn: function(){
return [
Meteor.subscribe("userAppointment", this.params.id)
]
},
data: function(){
var appointmentId = this.params.id;
return {
appointment: Appointments.findOne(appointmentId),
// patient: Meteor.users.findOne(Appointments.findOne(appointmentId).patientId)
}
}
});
Appointments.findOne(appointmentId) returns an object:
{
_id: "23efref34qr2",
reason: "coughing",
patientId: "785g45g4f"
}
When my data function only returns
appointment: Appointments.findOne(appointmentId)
it works. But if I have it also return
patient: Meteor.users.findOne(Appointments.findOne(appointmentId).patientId)
I get an error message (can't read property 'patientId' of undefined.) Huh? It was just defined on the line above!
To clarify, I think you should be allowing your data function to run (and rerun when collections are populated), but be careful to make sure your function doesn't throw an error when it runs before data is available. This is a general Meteor pattern.
data: function(){
var appointmentId = this.params.id,
appointment = Appointments.findOne(appointmentId);
return { appointment: appointment,
patient: Meteor.users.findOne(appointment ? appointment.patientId : null) }
}
Sorry about the formatting, I'm doing this from an awful phone...
The problem seems to be that it runs the data function() before running the waitOn, and is therefore timing dependent. I have seen the same problem, and also had to check if the data was actually there.
In my Meteor app I have some collections I would like to subscribe to immediately upon login, and other collections I would like to subscribe to when the user visits or revisits the initial home page, but not otherwise.
The first set of collections should always be subscribed to throughout, but the second set should be turned off and on as the user leaves and returns to the initial screen.
I have the following code:
Meteor.startup(function () {
Meteor.subscribe('collection_one', Meteor.user().profile.setting_one);
Meteor.subscribe('collection_two', Meteor.user().profile.setting_two);
});
Router.route('/', {
name: 'home',
path: '/',
template: 'home',
waitOn: function() {
return [
Meteor.subscribe('collection_three', Meteor.user().profile.setting_three),
Meteor.subscribe('collection_four', Meteor.user().profile.setting_four),
]
}
});
My problem is that immediately upon startup and immediately upon going to the home page, Meteor.user() returns undefined. I would like to wait until Meteor.user() is defined, and then take these actions. How can I do this?
Meteor.startup() does not run code as a reactive computation, so even though Meteor.user() is a reactive data source it won't trigger a computation.
The reactivity section of the docs has a list of functions that run code as reactive computations.
You can use Tracker (previously called 'Deps') to create a reactive computation, like this:
Tracker.autorun(function () {
if (Meteor.user()) {
Meteor.subscribe('collection_one', Meteor.user().profile.setting_one);
Meteor.subscribe('collection_two', Meteor.user().profile.setting_two);
}
});
But it looks like you're using Iron Router so you could also set a global waitOn() with Router.configure to solve it, like this:
Router.configure({
layoutTemplate: 'MasterLayout',
loadingTemplate: 'Loading',
notFoundTemplate: 'NotFound',
templateNameConverter: 'upperCamelCase',
routeControllerNameConverter: 'upperCamelCase',
// This method will re-run when ever Meteor.user() changes.
waitOn: function () {
// Making sure setting_one and setting_two are available (which they won't be initially)
var setting_one = Meteor.user() && Meteor.user().profile && Meteor.user().profile.setting_one;
var setting_two = Meteor.user() && Meteor.user().profile && Meteor.user().profile.setting_one;
// Subscribe to the published version of the server side collections
return [
Meteor.subscribe('collection_one', setting_one),
Meteor.subscribe('collection_two', setting_two)
];
}
});
The key is to use Tracker.autorun()
import { Meteor } from 'meteor/meteor';
import { Tracker } from 'meteor/tracker';
let username = ''
Tracker.autorun( function(currentComputation) {
if (Meteor.user()) {
username = Meteor.user().username
if (username) // do something with username
return
}
})
currentComputation is optional
I'm using subscriptions manager with iron-router and my problem is this one.
I have a collection "participants" with 2 publications: allParticipants and todayParticipants.
if I go to this page:
Router.map(function () {
this.route('winners', {
waitOn: function () {
return [subs.subscribe('allWinners'),
subs.subscribe('allParticipants')];
console.log("subscribed!");
},
data: function () {
return {
winners: Winners.find(),
participants: Participants.find(),
loginBox: "True"
}
}
});
AllParticipants publication is subscribed and put in cache by the subscription manager package.
If after this, I go to this page:
Router.map(function () {
this.route('participants', {
path: '/',
waitOn: function () {
return subs.subscribe('todayParticipants');
},
data: function () {
return {
participants: Participants.find()
}
}
});
I'm expecting to subscribe only the todayParticipants but as my subscription is automatically named "Participants", It uses the cached subscription from the previous page being allParticipants.
Is there a way to change the name of my subscriptions in order to have each of them in the right cache?
Thanks.
What I do in my waitOn function is first stop my subscriptions like
if (App.subs) {
for (name in App.subs) {
App.subs[name].stop();
}
}
And then I create new subscriptions
App.subs = {
settings: Meteor.subscribe('settings', project),
...
};
return [App.sub.settings, .....];
Hope this helps!
Today, there seems to be no solution to this problem.
More explanation here: https://github.com/meteorhacks/subs-manager/issues/11
What I'm doing now is using a very limited number of subscriptions (filtered mainly on user) and then I create as much data objects as I want filtering my subscriptions in different ways.
Im new to Meteor and Im trying to figure out how to run a function after a collection change.
I have a route(iron router) that subscribes to a collection with waitOn. Which just waits for the subscrition to be ready before rendering which is what I want.
waitOn: function () {
return Meteor.subscribe('collection', this.params._id);
},
Any changes to the collection will be updated on all the clients and rendered automatically.
How would I run a function once the collection has changed?
You can use the onData hook, provided that you're returning that data using the data helper. E.g this is what a route may look like
this.route('routename',
path : '/abc',
waitOn: function () {
return Meteor.subscribe('collection', this.params._id);
},
data: function() {
return Collection.findOne({_id: this.params.id});
}
onData: function() {
//Do something when the data found by the above changes
}
});