Meteor secure subscribe & publish - meteor

This Meteor code needs to publish one document which has field plateNum match value that is entered by the user.
Why is it not returning any thing? How to fix it?
//server.publications.js
Meteor.publish('myCol', function (plate) {
if (this.userId && plate) {
return myCol.find({plateNum: plate}, {fields: {a: 1, b: 1, c: 1, engineSize: 1 }});
}
});
The values of the fields 'a', 'b', 'c' may not be ready at the time of the user request but will be calculated by a backend worker and update the myCol
//client.main.js
Meteor.subscribe('myCol', dict.get('plateNum')); //<== stored info from user
Template.footer.events({
'click #info': () => {
searching = '<span class="note">Searching...</span>';
let plate = document.getElementById('plateNum').value;
plate = plate.replace(/\W/g, '').toLowerCase().trim(); //
dict.set('plateNum', plate); //<=== store user info here
let doc = myCol.findOne({plateNum: plate});
if (!doc || !doc.a) Meteor.call('aaa', plate);
if (doc && !doc.b) Meteor.call('bbb', {plateNum: plate}, () => {});
if (doc && doc.c && !doc.c) Meteor.call('ccc', {plateNum: plate}, () => {});
}
});

I guess it is because at the time your client code subscribes to myCol the this.userId is null therefore nothing is returned by server.
To fix this you need to make sure the user has been authenticated prior to subscribe
Update
This is the code you could use to fix it:
Template.footer.onCreated(function() {
// use this.autorun over Tracker.autorun
// so that the code below will be clear on onDestroy event
this.autorun(function() {
if(Meteor.userId()) {
Meteor.subscribe('myCol', dict.get('plateNum'));
}
});
});

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.

Meteor subscription is not stopping

I've got what should be a relatively simple issue. I set a session, then a subscribe to a collection using the string stored in the session. But when that session changes, I need to clear the subscription data and start again.
My code is as follows:
let subscriptionReady;
let filteredResults = [];
let rawResults = [];
let county = Session.get('county');
let type = Session.get('type');
This is mostly just prep work to create some empty objects to populate later. This all gets set on a click event. After we set these placeholder objects we go and subscribe by those sessions:
if (county && !type) {
return function() {
if (subscriptionReady) {
subscriptionReady.stop();
}
filteredResults = [];
rawResults = [];
subscriptionReady = Meteor.subscribe('resourcesearch', county, {
onReady: () => {
rawResults = resourceCollection.find({}, { sort: {score: -1} }).fetch();
rawResults.forEach((result) => {
if (result.score) {
filteredResults.push(result);
}
});
}
});
}
At the third line I run a check to see if subscriptionReady exists, then it will have the stop method available. So then I run it. But, it doesn't actually stop anything.
What am I missing?
After trial and error, I've got it solved. The issue was the placement of the stop call. I no longer have to check if subscriptionReady exists, instead I stop the subscription inside of the onReady method:
return function() {
filteredResults = [];
rawResults = [];
subscriptionReady = Meteor.subscribe('resourcesearch', county, {
onReady: () => {
rawResults = resourceCollection.find({}, { sort: {score: -1} }).fetch();
rawResults.forEach((result) => {
if (result.score) {
filteredResults.push(result);
}
});
subscriptionReady.stop();
}
});
It's .stop() not .stop docs
Also you can probably avoid your filtering loop by including score in your query. Are you looking for documents where the score key exists {score: {$exists: true}} or just where it is non zero {$score: {$ne: 0}}?
Also you shouldn't need to clear the subscription and start again. If you make your subscription parameter resourcesearch a reactive data source then the subscription will automatically update to give you the documents you need. Starting/stopping a subscription in response to a search would be an anti-pattern.

Non-reactive and reactive data in Meteor (same helper)

I've got one view displaying some pictures published by users with some data (let's image Instagram).
I already have these pictures as non-reactive data (otherwise you could see many updates) but these images have one button to like the picture. If I have this as non-reactive data I can't see when I click on "Like" the filled heart (I need to refresh).
This is my subscribe function:
this.subscribe('food', () => [{
limit: parseInt(this.getReactively('perPage')),
//skip: parseInt((this.getReactively('page') - 1) * this.perPage),
sort: this.getReactively('sort')
}, this.getReactively('filters'), this.getReactively('searchText'), this.getReactively('user.following')
]);
And this is my helper:
food() {
const food = Food.find({}, {reactive: true}, {
sort: this.sort
}).fetch().map(food => {
const owner = Meteor.users.findOne(food.owner, {fields: {username: 1, avatarS: 1, following: 1}});
food.avatarS = owner && owner.avatarS;
food.username = owner && owner.username;
if (food.likes.indexOf(Meteor.userId()) == -1) {
// user did not like this plate
food.liked = false;
} else {
// user liked this plate
food.liked = true;
}
return food;
});
}
Is possible to have a non-reactive model but with some reactive properties on it?
I'm using Angular 1.X with TS btw
Thanks in advance!
PS: is it normal that this works as non-reactive when I change reactive to true?
Modification to your code:
//console.log(food.likes);
this.subscribe('reactiveFoodData', {ownerId: food.owner, userId: Meteor.userId()}).subscribe(()=>{
console.log(this.user);
});
// THIS IS THE PUBLISH METHOD LOCATED IN THE SERVER SIDE:
Meteor.publish('reactiveFoodData', function(params: {ownerId:string, userId:string) {
const owner = Meteor.users.findOne(params.ownerId);
if (!owner) {
throw new Meteor.Error('404', 'Owner does not exist');
}
let result = {};
result.avatarS = owner.avatarS;
result.username = owner.username;
const food = Food.find({});
result.liked = !(food.likes.indexOf(params.userId) == -1);
return result;
});
You have few problems:
1. The reactive flag is true by default, you do not need to set it.
2. The function find is accepting only two arguments, not 3.
Should be:
const food = Food.find({}, {reactive: true, sort: this.sort})
If you need some, subset of data to be reactive only (from some collection). You could create a specific Method (which udpates only "likes").
https://guide.meteor.com/methods.html
UPDATE:
Here is how you write a method with return parameter (check two examples, with Future and without):
How to invoke a function in Meteor.methods and return the value
UPDATE2:
You have lost reactivity when you used fetch(). Because you moved from reactive cursor to just simple array over which you map values. Do not expect reactivity after fetch(). If you want fetch or do not want to use Cursors, you could wrap the find inside Tracker.autorun(()=>{}) or utilize publish/subscribe.
Note: But be careful, if you somehow manage to get "empty" cursor in find(), your Tracker.autorun will stop react reactively. Autorun works only if it has something to watch over.
The main point with method, is that if you want to have one time non-reactive action for something. You define the method on server:
Meteor.methods({
myMethod: ()=> {
return "hello";
}
});
And you can call it from client with:
Meteor.call('myMethod', (error, result) => {
console.log(result); // "hello"
});
Instead of working with pure collections. You could start using publish/subscribe. On server you publish 'likes' and on client you just listens to this new reactive view. E.g.,
Meteor.publish('likes', (options: {owner: string, likes: Array<any>}) => {
let result: any = {}
const owner = Meteor.users.findOne(options.owner, username: 1, avatarS: 1, following: 1}});
result.avatarS = options.owner && options.owner.avatarS;
result.username = options.owner && options.owner.username;
result.liked = !(options.likes.indexOf(Meteor.userId()) == -1)
return result;
});
On client side: Meteor.subscibe('likes', {food.owner, food.likes}).subscribe(()=>{});
This is just off the top of my head.
Have you tried looking at Tracker ? https://docs.meteor.com/api/tracker.html
But more specifically the method Tracker.nonreactive
https://docs.meteor.com/api/tracker.html#Tracker-nonreactive

Meteor reactive transform

I have a mobile app in development and I'm transforming one of the collections to get the user last seen time, avatar etc.
PlayerRecord.prototype = {
constructor : PlayerRecord,
getAssociatedUser: function () {
return Meteor.users.findOne( this.user_id );
},
lastSeenFormatted: function () {
var user = this.getAssociatedUser();
return (user && user.last_seen) ? user.last_seen : 'Never';
}
}
My problem is that, if the user last seen returns Never initially but then the user is seen, my string return over there is not updated...obviously.
How would you advise me to handle this situation?
Did you check whether any user had a value for last_seen? This field has to be explicitly published.
According to the Meteor docs (http://docs.meteor.com/#/full/meteor_user):
By default, the current user's username, emails and profile are
published to the client. You can publish additional fields for the
current user with:
// server
Meteor.publish("userData", function () {
if (this.userId) {
return Meteor.users.find({_id: this.userId},
{fields: {'last_seen': 1}});
} else {
this.ready();
}
});
// client
Meteor.subscribe("userData");

Adding new users to a collection and having them render on a list automatically?

So im doing the leaderboard example on the meteor site but instead of the predefined data I start off with, I want to create a new name and score that automatically appears on the screen when someone creates an account, so at this point I get the name and the score on the screen only after I create an account and hit the refresh button on the browser, what do I want to do so that I don't have to hit the refresh button and the user login name and score automatically appears on the screen?
do I want to use deps.flush() or meteor.render somehow?
server.js
// newUser Method
Meteor.methods({
newUser: function() {
var user = Meteor.user();
userVar = {
name: user.username,
score: 0
};
Players.insert(userVar);
}
});
client.js
Deps.autorun(function() {
Meteor.call('newUser');
});
Template.leaderboard.players = function () {
return Players.find({}, {sort: {score: -1, name: 1}});
};
Template.leaderboard.selected_name = function () {
var player = Players.findOne(Session.get("selected_player"));
return player && player.name;
};
Template.player.selected = function () {
return Session.equals("selected_player", this._id) ? "selected" : '';
};
Template.leaderboard.events({
'click input.inc': function () {
Players.update(Session.get("selected_player"), {$inc: {score: 5}});
}
});
Template.player.events({
'click': function () {
Session.set("selected_player", this._id);
}
});
If your starting point is a working version of the example then you should be seeing reactive changes to the web page each time the Players collection changes. Deps.flush or Meteor.render are unnecessary.
The Deps.autorun() function you have is only called once when the client starts. At that point you may not have a user and your method will fail when you try to get a username from the null variable, 'user'.
To trigger the autorun each login and when you have a user you need it to refer to a reactive data source. If you rewrite it like this you should see a new player showing up each time a user logs in:
//on client
Deps.autorun( function(){
if ( Meteor.userId() ){
Meteor.call('newUser');
}
});
I also wonder if your method on the server will have a problem as this.userId is how I usually get the user information inside a method. Here is an alternative to avoid the method and just insert the player on the client:
//on client
Deps.autorun( function(){
var user = Meteor.user();
if ( user ) { //insert will run on login or any change in the user
var userVar = {
name: user.username,
score: 0
};
Players.insert(userVar);
}
});
So I assume then that "player" records belong to a user in some way? So when you create a new user, you create their new default player record?
Maybe you just need your helpers to check that a player record for the user exists, and if not, create it.
Template.leaderboard.players = function () {
var players = Players.find({/* Get players for this user */ }, {sort: {score: -1, name: 1}});
if(!players) {
players = /* Insert default player record */
}
return players;
};

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