Objection.js: Add filter method on ManyToMany join table.

[keepcosmos]

Is there any way to add filter options on ManyToMany through?

like,

goodFriends: {
  relation: ManyToManyRelation,
  to: XX,
  from: YY,
  through: {
    from: 'XX.id'
    to: 'YY.id',
    filter: (builder) => { builder.where('relationships.type', 'good') }
  }
}

[koskimas]

Not currently, but that could be useful addition. It could be used as a solution to https://github.com/Vincit/objection.js/issues/837

[ericmuyser]

This would allow N:M polymorphic relationships like in this answer: https://github.com/Vincit/objection.js/issues/19#issuecomment-389356230

But instead of the filter field being on the relation table, it would be on the join table, which is freaking awesome (and how I thought it worked until I kept running into this error and analyzed that answer further).

builder.where('relationKey', 'tags') - fails. it's trying to do this on the tags table not the nodes table.

I have a generic exclusive arc table that allows me to build relationships on the fly. I put the extra: ['relationKey'] on that relation thinking it would work. It doesn't. So I'll need a relationKey on every single table. And that row can't be re-used. And I can't really validate the data integrity since that field will get overwritten and isn't on the same table so I can't use a constraint. Sigh.

Edit: Looks like I can do 'tags_join.relationKey': 'tags' in my query and that works too.

[lexa0303]

Any updates on this?

[ELBEQQAL94]

I'm stack on the same issue, any update on this?

[haydernativapps]

Any update about this issue?

[sayhicoelho]

Any update? This feature is needed...

[bbrizzi]

I found a workaround by defining the intermediary table in my models and aliasing the fields using virtual attributes.

I have a polymorphic N:M relationship between Devices and Configurations through a ConfigurationLink pivot table.

In /models/ConfigurationLink :

      config: {
        relation: Model.HasOneRelation,
        modelClass: Configuration,
        join: {
          from: 'configuration_links.configuration_id',
          to: 'configurations.id'
        }
      },

In /models/Device.js :

      config_link: {
        relation: Model.HasManyRelation,

        modelClass: ConfigurationLink,

        join: {
          from: "devices.id",
          to: "configuration_links.configurable_id",
        },

        filter (builder) {
          // Filter for polymorphic relationship
          builder.where("configurable_type", "device");
          builder.where("configuration_links.deleted", false);
        }
      },

And :

  static get virtualAttributes() {
    return ['config'];
  }

  config() {
    return this.config_link.map((cl) => (
        {
        ...cl.config,
       premium: cl.premium, // Extra field fetched from the pivot table
       })
    );
  }