Migrating Coffescript to ES2015 code (Meteor code) - meteor

I am migrating some code from Coffescript to ES2015. I would like the result of a transpile to look like this:
Meteor.users.deny({
update: function() {
return true;
}
});
In Coffescript, this does it:
Meteor.users.deny
update: ->
true
Is it possible to code this in ES2015 so that the output matches the original code?
Addendum:
This is what I tried on babel with Evaluate checked
Meteor.users.deny({
update: function () {
return true;
}
});
and
Meteor.users.deny({
update: () => true
});
both of which output:
Meteor.users.deny({
update: function update() {
return true;
}
});
The anonymous function becomes named (update)
So why is this a "problem"? I am trying to understand ES2105 and something I could easily do in Coffeescript does not seem possible in ES2015. I was trying to confirm that - or see if I was misusing ES2015 or missing a capability of it
This question is similar but does solve what I am trying to do. Any guidance would be appreciated

This is what I believe it should look like:
Meteor.users.deny({
update: () => true;
});
deny is a function that receives an object as a parameter. Your code set deny to a new function.

Related

Meteor pagination

i am struggling with adding in pagination for my forums. Could you help me out? Basically, I was expecting on my forums page, to only see 10 posts. but it is returning all of them. The "Load More" button also does nothing (it seems like).
I am using this package: Paginated Subscription
Here is the code I am using:
if (Meteor.isClient) {
Deps.autorun(function() {
var handle = Meteor.subscribeWithPagination('posts',10);
});
Template.postsList.helpers({
'posts': function(){
return Posts.find({});
}
});
Template.postsList.events({
'click .btn': function(){
handle.loadNextPage();
}
})
}
if (Meteor.isServer) {
Meteor.startup(function () {
Meteor.publish("posts", function(limit){
return Posts.find({}, {limit: limit});
});
});
}
I don't think the var handle = Meteor.subscribeWithPagination('posts',10); Needs to be in the Deps block unless you are passing some reactive parameter to thehandle.
See this Issue on Github.
You can use Kurounin subscribe based pagination.It works for me.In atmospherejs, there is an another react pagination you can check it in Kurounin repository
I have already answered this kind of pagination to one of question. Please refer the exact code that can help you.
Meteor Pagination Issue
In your publication you must use sort (as documentation says)
// Using sort here is necessary to continue to use the Oplog Observe
Driver!
// https://github.com/meteor/meteor/wiki/Oplog-Observe-Driver
Meteor.publish("posts", function(limit){
return Posts.find({}, {
limit: limit,
sort: {
createdAt: -1
}
});
});

How can I be updated of an attribute change in Meteor?

I have a template that subscribes to a document. Everything works fine in the DOM and Blaze updates as soon as an attribute used in the template helpers is changed.
I also have some custom logic that doesn't appears in the DOM and depends on the document attributes. How can I call a function to change that logic when an attribute is updated?
I'm looking for something like this.data.attr.onChanged where this would refer to the template and this.data is the data send to the template, as usual; or a Meteor function that is rerun on change where I could put my callback in.
I hoped that template.onRendered would be recalled, but that's not the case.
I've read a lot about reactive variables, but could not find how they could be useful here.
[edit] the change is coming from the server that is communicating with another service
I've tried Tracker.autorun like this:
Template.editItem.onRendered(function() {
var self = this;
Tracker.autorun(function () {
console.log("tracker", self.data.item.socketId);
});
});
And the corresponding route is:
Router.route('editItem', {
path: '/edit/:_id',
waitOn: function () {
var sub = Meteor.subscribe('item', this.params._id);
return [sub];
},
data: function () {
return {item: Items.findOne(this.params._id)};
},
action: function () {
if (this.ready())
this.render();
}
});
At some point, the property socketId gets removed from the corresponding document by the server and I'm sure of that since I've checked in the shell, but the tracker doesn't rerun.
Use Template.currentData().item.socketId instead of self.data.item.socketId, this will give you reactivity.
And in templates generally, use self.autorun instead of Tracker.autorun (unlike Tracker.autorun, this will ensure that the autorun is stopped when the template is destroyed). Likewise, if you want to subscribe in a template, use self.subscribe instead of Meteor.subscribe.
Code to see if Template.currentData() works for you:
Template.editItem.onRendered(function() {
var self = this;
self.autorun(function () {
console.log("tracker", Template.currentData().item.socketId);
});
});
I'm not sure if I got you right, you just want to observe your html inputs and apply the new value to your helper method(s) on change?!
If so, you could use session variables to store your temporary UI state:
// observe your input
Template.yourTemplate.events({
"change #inputA": function (event) {
if(event.target.value != "") {
Session.set("valueA", event.target.value);
}
}
}
// apply the changed value on your helper function
Template.yourTemplate.helpers({
getSomeData: function() {
var a = Session.get("valueA");
// do something with a ..
}
}
In meteor's official todo app tutorial this concept is also used.
If you need to re-run something which is not part of DOM/helper, you can use Tracker.autorun. According to meteor docs, Run a function now and rerun it later whenever its dependencies change.
here's the docs link
Try moving the subscription into Tracker.autorun
Template.editItem.onRendered(function() {
var self = this;
Tracker.autorun(function () {
Meteor.subscribe('item', this.params._id);
console.log("tracker", self.data.item.socketId);
});
});
Of course you can't use this.params there so you can store this as a Session variable

MeteorJs getting querystring data for templatehelper use

I am new to Meteor and have a slight problem with Meteor.
I created a link which is
http://localhost:3000/game?id=7lJ8F
how would I get the id value in the query string and return it to a helper.
I have looked for answers but found none.
Router.route('/game/:_id', function(){
Session.set("gameid",this.params.query.id);
});
Template.gamebefore.helpers({
ids: function () {
return Session.get("gameid");
}
});
I know this is all wrong but I am quite desperate to find an answer so any will help. Thank You!
How to handle and get the parameters of an url are described in the guide of iron router
You might miss the _:
this.params.query.id
should be
this.params.query._id
or vice versa, since in your url is
/game?id=7lJ8F
in your route its
Router.route('/game/:_id', function(){
You don't need an id in the route:
Router.route('/game', function(){
Session.set("gameid",this.params.query.id);
});
Template.gamebefore.helpers({
ids: function () {
return Session.get("gameid");
}
});
As a note, instead of using http://..../game?id=somegameid, you might want to use a more REST approach by using http://.../game/somegameid, in which case, you need this route:
Router.route('/game/:_id', function(){
Session.set("gameid",this.params._id);
});
Template.gamebefore.helpers({
ids: function () {
return Session.get("gameid");
}
});

Durandal: How to route away from current view within that view's activate() function?

I have the following:
function activate(routeData) {
// make dataservice call, evaluate results here. If condition is met, reroute:
if (true){
router.navigateTo("#/someRoute");
}
alert ("should not be shown");
}
The alert is getting hit however, and then the view changes.
How do I fully navigate away from the current item and prevent any further code in that vm from being hit?
Update:
I tried using guardroute but I have to activate the viewModel to call the dataservice that returns the data that determines whether or not I should re-route. Using guardroute totally prevents the dataservice from getting called (since nothing in the activate function will get hit).
I also tried returning from the if block but this still loads the view / viewAttached / etc so the UX is glitchy.
The following worked for me in Durandal 2.0:
canActivate: function() {
if(condition)
return {redirect: 'otherRoute'};
return true;
}
activate: // Do your stuff
It's mentioned in the documentation: http://durandaljs.com/documentation/Using-The-Router.html
Here's #EisenbergEffect answer to a quite similar discussion in google groups.
Implement canActivate on your view model. Return a promise of false,
then chain with a redirect.
You might want to give #JosepfGabriel's example (discussion) a try in Durandal 1.2. Check the correct router syntax for your Durandal version, you might have to substitute it with something like router.navigateTo("#/YourHash", 'replace').
canActivate: function () {
return system.defer(function (dfd) {
//if step 2 has a problem
dfd.resolve(false);
})
.promise()
.then(function () { router.navigate("wizard/step1", { trigger: true, replace: true }); });
}
However this is NOT working in Durandal 2.0 and there's a feature request https://github.com/BlueSpire/Durandal/issues/203 for it.
You can't call redirect into the active method.
You can override the guardRoute method from router, to implement redirections.
You can do somehting like that:
router.guardRoute= function(routeInfo, params, instance){
if(someConditios){
return '#/someRoute'
}
}
You can return a promise, true, false, the route to redirect... You can find more information about that in the next link: http://durandaljs.com/documentation/Router/
Rainer's answer was pretty good and works for me adding this small fix.
Inside the then() block simply call the navigation like this
setTimeout(function() { router.navigateTo('#/YOUR DESTINATION'); }, 200);
that should fix your problem. The setTimeout does the trick. Without it the newly navigated page catches the old NavigationCancel from the previous one.
Adding a return in your if (true) block should fix this.
function activate(routeData) {
if (true){
router.navigateTo("#/someRoute");
return;
}
alert ("should not be shown");
}

How can I access the name of the current route in meteor when using meteor-router?

I'm building an app using meteor and meteor router, and I would like to make a template helper for checking if the route is a specific one ({{#ifRouteIs login}}{{/ifRouteIs}}).
I had the same issue. Building on your answer, I found a working solution. It needs to go in the client side of Meteor.
Handlebars.registerHelper('ifRouteIs', function (routeName, options) {
if (Meteor.Router.page() === routeName) {
return options.fn(this);
}
return options.inverse(this);
});
According to meteor-router's README, you can get the current page with Meteor.Router.page(), so the helper might look like this:
Handlebars.registerHelper('ifRouteIs', function (routeName) {
return Meteor.Router.page() === routeName;
});

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