Trigger global meteor subscription without iron router - meteor

This should be an easy one.
Here's what I would like:
Page 1: Subscribe to 'List' collection
Page 2: display items from 'List' collection (user then selects an item from the list, returning the _id)
Page 3: subscribe to 'Data' collection using _id <- STAY SUBSCRIBED FROM NOW ON, ON EVERY PAGE, WITHOUT THE USE OF IRON ROUTER
I've messed around with Template.subscribe, Template.onCreated etc. but it's Friday and I'm sure this is elementary stuff so I thought I'd ask.
Cheers!

Here's how I did it:
User logs in -> render userLayout -> set currentPage to
loading
If user has already selected a project, set currentPage to userSplash (else set currentPage to userProjects where they will select a project and then go to userSplash)
Template.userLayout.created = function() {
Session.set('currentPage', 'loading');
return Meteor.subscribe('projects', user.profile.company_id, function() {
if (currentProject_id !== void 0) {
return Session.set('currentPage', 'userSplash');
} else {
return Session.set('currentPage', 'userProjects');
}
});
};
Render userSplash -> subscribe to required project data -> load dashboard when finished
Template.userSplash.rendered = function() {
return Meteor.subscribe('tasks', currentProject_id, function() {
return Session.set('currentPage', 'userDashboard');
});
};
(this answer provided some useful info)

Related

Tracker autorun using findone

I have this piece of code in client side:
Tracker.autorun(function () {
if (params && params._id) {
const dept = Department.findOne({ _id: params._id }) || Department.findOne({ name: params._id });
if (dept) {
}
}
});
params will be passed into the url. So, initially we won't have the department data and the findOne method will return null, and then later on, when data arrives, we can find the department object.
But if user enters an invalid id, we need to return them 404. Using tracker autorun, how can I distinguish between 2 cases:
a. Data is not there yet, so findOne returns null
b. There is no such data, even in server's mongodb, so findOne will also returns null.
For case a, tracker autorun will work fine, but for case b, I need to know to return 404
I would suggest you to subscribe to data inside template, like below so you know when subscriptions are ready, then you can check data exists or not
Template.myTemplate.onCreated(function onCreated() {
const self = this;
const id = FlowRouter.getParam('_id');
self.subscribe('department', id);
});
Template.myTemplate.onRendered(function onRendered() {
const self = this;
// this will run after subscribe completes sending records to client
if (self.subscriptionsReady()) {
const id = FlowRouter.getParam('_id');
const dept = Department.findOne({ _id: params._id }) || Department.findOne({ name: params._id });
if (dept) {
// found data in db
} else {
// 404 - no department found in db
}
}
});
If you are using Iron-Router, you may try this hack.
Router.route('/stores', function() {
this.render('stores', {});
}, {
waitOn: function() {
return [
Meteor.subscribe('stores_db')
];
}
});
The sample code above will wait for the subscription "stores_db" to complete, before rendering anyhing. Then you can use your findOne logic no problems, ensuring that all documents are availble. This suits your situation.
This is what I used to do before I completely understand MeteorJS publications and subscriptions. I do not recommend my solution, it is very bad to user experience. Users will see the page loading forever while the documents are being download. #Sasikanth gave the correct implementation.

Ionic and SQLite wait until database info is loaded

I have a project on Ionic where I need to render some information of the database in the home page, something like a TODO program.
I already have some information on the database and I'm trying to render the list of items but I have the next problem:
First the home page is loaded without any result
Then the data from the database is loaded and printed on the screen
The problem is I want the view to wait until the database info is loaded until showing anything, I'm wondering if I can use some kind of loading icon.
I've followed the answer here: Open database before main controller is called in Ionic and SQlite
I have the database initialization working but as I've said, the data is loaded after the view is rendered.
I've tried using $ionicLoading but I didn't get any good result
This is my view:
.controller('homeCtrl', function ($scope, $state, $cordovaSQLite, DB) {
$scope.$on('$ionicView.enter', function() {
tasks = []
var query = "SELECT * FROM task;";
$cordovaSQLite.execute(DB.db, query, []).then(function(results) {
if(results.rows.length > 0) {
for (i=0; i<results.rows.length; i++){
console.log("SELECTED -> " + results.rows.item(0).title);
$scope.tasks.push(results.rows.item(i))
}
} else {
console.log("No results found");
}
}, function (err) {
$scope.tasks = [];
console.error(err);
});
$scope.tasks = tasks;
});
})
This is a video example of the issue I'm having right now:
https://youtu.be/H2fUYQuV3xg
Finally I found a solution following the advice of using resolve in my routes.
.state('home', {
url: '/',
templateUrl: 'templates/home.html',
controller: 'homeCtrl',
resolve: {
tasks: function(DB) {
return DB.getTasks();
});
}
}
})
I have a factory called DB where I have some functions to retrieve data from the database. On this example I load the tasks before entering on the URL using DB.getTasks()
To load the variable tasks resolved on the route I have to add the variable name on the function like this:
app.controller('homeCtrl', function (tasks) {
$scope.tasks = tasks;
})

user object not loaded after logging out and quickly logging back in in Meteor

I am facing a strange behaviour, and can't debug it properly. I need your help.
If I log out of Meteor, everything seems fine.
If I wait for around 2 seconds and log back in again, everything is still very fine. But if I logout and quickly login again, right after the login process, the Meteor.user() object is set to null, which leads my router to redirect the user back to the login page.
Any idea why this is happening, and how could I prevent it?
I have spent 2h trying several things without success. Any suggestion is most welcome.
EDIT
This is my global onBeforeAction function :
Router.onBeforeAction(function() {
// Ensures the user is logged in
if (!Meteor.userId()) {
please_login();
}
// Email address not verified for 24h? Please verify it!
else {
var self = this;
// Waits for the user object to be passed over DDP
function wait_for_user_data() {
if (Meteor.user() && Meteor.user().emails && Meteor.user().profile) {
var user = Meteor.user();
var now = new Date().getTime();
var ca = user.createdAt.getTime();// Created At
var cs = (now - ca) / (24 * 60 * 60 * 1000);// Created Since (in days)
var urls = ["email_verification_required", "email_verification"];
if (cs > 1 &&
!user.emails[0].verified &&
urls.indexOf(self.url.split("/")[1]) == -1) {
Router.go("email_verification_required");
}
else {
self.next();
}
}
else {
setTimeout(wait_for_user_data, 500);
}
}
wait_for_user_data();
}
},
{except: ['home', 'login', 'register', 'password_recovery', "email_verification", "profile"]})
What actually happens is the following :
When I login right after having logged out, self.next() is called, but the current user properties (Meteor.user().emails and Meteor.user().profile) aren't loaded yet for some reason. They are undefined. As you can see, I tried to work around this by waiting until they are defined, but then I receive the following error message :
Route dispatch never rendered. Did you forget to call this.next()
in an onBeforeAction?
This seems to cause Meteor to set Meteor.user() to null, and so my user gets redirected to the login page...
EDIT BIS
This is how I am handling the publish/subscribe of the users data. I have 2 different pub/sub set, one for all users, and the other one for the logged in user only.
Meteor.publish('users', function() {
var args = {};
var fields = {
'_id': 1,
'createdAt': 1,
'profile.firstname' : 1,
'profile.lastname' : 1,
'profile.lang' : 1,
};
// Only admins can access those sensible information
if (this.userId && Roles.userIsInRole(this.userId, 'admin')) {
fields["emails"] = 1;
fields["profile.celular"] = 1;
args : {$ne : {_id: this.userId}};
}
return Meteor.users.find(args, {fields: fields});
});
Meteor.publish('user', function() {
return Meteor.users.find({_id: this.userId});
});
This is how I subscribe to those two publications within my router's configurations :
Router.configure({
layoutTemplate: 'layout',
loadingTemplate: 'loading',
waitOn: function() {
return [Meteor.subscribe('user'), Meteor.subscribe('users')];
},
});
Without a code example (and knowing which router you're using) I'm going to take a guess that you're router code looks something like :
if (!Meteor.user()) {
//... redirect or change tempalte etc
}
There is another value you can check,
if (!Meteor.user() && !Meteor.loggingIn()) {
//... redirect or change tempalte etc
}
you can use various combinations of these to handle the login state, such as having a logging in loading view etc
With more information
The redirect is being called in a callback, currently for the login with password function, having a look at the docs it should be called on the onLogin callback linked as this ensures that login was successful, though doing the redirect here, may not provide the same range of control as doing this in a reactive context such as a before hook on a controller, or an autorun function created in the login template onCreated callback.
The way I've deal with this in the past is to define an explicit subscription to the user object then waitOn that subscription in the router. Much simpler than writing a polling loop but mostly I did it because I needed specific fields that didn't come over by default. Hopefully this can help you with your problem.
Server:
Meteor.publish('me',function(){
if ( this.userId ){
// return the fields I need
return Meteor.users.findOne({ _id: this.userId },{ fields: { field1: 1, field2: 1, ... }});
}
else this.ready();
});
Router:
waitOn: function(){
return Meteor.subscribe('me');
}

Adding an array object to Users collection in Meteor.js

I'm very new to Meteor.js and I'm finding the documentation a bit hard to understand.
I'm starting with a very simple app where Users will simply be allowed to add existing Games to their profile by clicking a button. The Games are stored in another Meteor Collection.
In rails I would just create a has_and_belongs_to_many relationship but that isn't how Meteor works. I thought the best way would be to add an empty array when the user's account is created - then, when they click the "add game" button it would pass the game's title into the users array.
I have this in my /server/users.js file:
Accounts.onCreateUser(function(options, user){
user.games = [];
return user;
});
Meteor.methods({
addGame: function(title) {
Meteor.users.update(Meteor.userId(), { $addToSet: { games: title}});
}
});
And I'm making a call to the addGame method in my /client/views/games/games_list.js file as such:
Template.gamesList.events({
'click .add-to-chest-btn': function(e){
var title = $(e.target).attr('name');
e.preventDefault();
Meteor.call('addGame', title, function(title){ console.log(title)});
}
});
Am I on the right track or is there a better way to do this?
You're on the right track, but do declare an array instead of an object:
Accounts.onCreateUser(function(options, user){
user.games = [];
return user;
});
Push the value directly instead of an object, and use $addToSet to avoid duplicates in case you push the same gameId multiple times:
Meteor.methods({
addGame: function(gameId) {
Meteor.users.update(Meteor.userId(), { $addToSet: { games: gameId }});
}
});

Detecting which reactive query was triggered

I have an probably not so unique issue of having a complicated meteor app.
I have several actions which are causing parts of the page to refresh which really aren't needed. But I'm having trouble locating which find() (or multiple find()'s ) is the one being triggered. I know the Collection in question, just not which find().
I could use observeChanges on every find I use, but that would be a lot of extra code.
Is there an easy way to see what is being triggered and by what?
Thanks!
Here is a render logging function you might find useful. It logs the number of times each template is rendered to the console. You know if a template is re-rendered after initial page load, it's because a reactive data source that it relies on has changed. Either this reactive data source could have been accessed in a helper method, or the template is a list item (i.e. inside an {{#each ...}} block helper) and a list item was added/moved/removed/changed. Also keep in mind that child templates call their parent's rendered callback when the child is rendered or re-rendered. So, this might confuse you into thinking the parent has actually been taken off the DOM and put back, but that's not true.
So, you can call this function at the end of your client code to see the render counts:
function logRenders () {
_.each(Template, function (template, name) {
var oldRender = template.rendered;
var counter = 0;
template.rendered = function () {
console.log(name, "render count: ", ++counter);
oldRender && oldRender.apply(this, arguments);
};
});
}
EDIT: Here is a way to wrap the find cursor to log all changes to a cursor to the console. I just wrote a similar function to this for a new package I'm working on called reactive-vision. Hopefully released soon.
var wrappedFind = Meteor.Collection.prototype.find;
Meteor.Collection.prototype.find = function () {
var cursor = wrappedFind.apply(this, arguments);
var collectionName = this._name;
cursor.observeChanges({
added: function (id, fields) {
console.log(collectionName, 'added', id, fields);
},
changed: function (id, fields) {
console.log(collectionName, 'changed', id, fields);
},
movedBefore: function (id, before) {
console.log(collectionName, 'movedBefore', id, before);
},
removed: function (id) {
console.log(collectionName, 'removed', id);
}
});
return cursor;
};
Thank you #cmather for the idea.
Her is Meteor 1.3 adapted and more advanced version of logRenders
// Log all rendered templates
// If filter is set, only templates in filter will be logged
// #params filter - name or names of template to filter
logRenders = function logRenders (filter) {
for (name in Object(Template)){
if (filter && !Array.isArray(filter)) filter = [filter];
var template = Template[name];
if (!template) continue;
if (filter && filter.indexOf(name) == -1){
// Clear previous logRenders
if ('oldRender' in template) template.rendered = template.oldRender;
delete template.oldRender;
continue;
}
var t = function(name, template){
if (!('oldRender' in template)) template.oldRender = template.rendered;
var counter = 0;
template.rendered = function () {
console.log(name, ++counter, this);
this.oldRender && this.oldRender.apply(this, arguments);
};
}(name, template);
};
};

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