Subscription reactivity issue for many type links

[gabrielcazacu96]

Issue

Subscription query result does not get updated when a new link is added.

Example

1. Initial data

Groups:
[{ _id: 'groupId1'}, {_id: 'groupId2'}]
Authors:
[{_id: 'authorId1', groupIds: ['groupdId1']}, {_id: 'authorId2', groupIds: ['groupdId2']}]

2. Query

const query = createQuery({
    groups: {
        authors: {
            groupIds: 1,
        }
    }
});

3. If I add groupId1 to the groupIds of authorId2, the query result does not update.
4. Expected subscription query result

[{ 
_id: 'groupId1',
authors: [{_id: 'authorId1', groupIds: ['groupdId1']}, {_id: 'authorId2', groupIds: ['groupdId1', 'groupdId2']}]
},
{
_id: 'groupId2',
authors: [{_id: 'authorId2', groupIds: ['groupdId2']}]
}]

4. Actual subscription query result never changes

[{ 
_id: 'groupId1',
authors: [{_id: 'authorId1', groupIds: ['groupdId1']}]
},
{
_id: 'groupId2',
authors: [{_id: 'authorId2', groupIds: ['groupdId2']}]
}]

Additional info

• This seems to happen only for many type links
• Issue seems to be related to the meteor-publish-composite package and how the cursor events are triggered.
• Issue happens only if the linked object is already linked to another parent object in the query. In the example, the author is already linked to another group.

[gabrielcazacu96]

Added demonstration test: #482
Only works the first time because after that, the mongodb data is changed.

[gabrielcazacu96]

Added fix attempt to meteor-publish-composite: Meteor-Community-Packages/meteor-publish-composite#177

[gabrielcazacu96]

Thanks to #179 this should no longer be an issue once meteor-publish-composite is updated to version v1.8.8

[StorytellerCZ]

@gabrielcazacu96 per your comment this should be fixed in v1.5