My Reactive aggregation method is not reactive

help
1

Hi,

I need some help to resolve this issue.

Basically I want to show in the UI a list of items coming from a MongoDb collection.

As the collection has multiples items for the same “ID”, I need to do an aggregation to select the higher one.

My problem is the view doesn’t update if I change any parameter of this collection.

The implementation is:

  • View:
{{#each getList}} {{ID}} {{version}} {{dataexample}} {{/each}}
  • Client side

Template.example.helpers({
‘getList’: function() {
return ReactiveMetod.call(‘listItems’);
}
});

  • Server side

Meter.methods({
‘listItems’: function(){
var final = [];
var pipeline = [{
$group: {
"_id": “$ID”,
version: {$max: “$version”}
}
}];

var result = CollectionItems.aggregate(pipeline);
result.forEach(function(entry) {
  final.push(
    CollectionItems.findOne({
      ID: entry._id,
      version: entry.version
    })
  );
});
return final;

});

So if something change of this collection, it doesn’t update the view.

I was thinking to force reload every 5 seconds but I was expecting to find a way to keep the reactivity/multicollaboration in realtime.

Many thanks

2

Aggregation is not reactive by default in Meteor. However, there is a reactive-aggregate package which you could consider using to provide this.

2 Likes
3

Okey, I am going to try.

Many thanks

1 Like