Entry.js

module.exports = {

  attributes: {

    // The participation that submitted this entry
    participation: {
      model: 'participation',
      required: true
    },

    // TODO: Do we need this, can't we get it from participation.contest?
    contest: {
      model: 'Contest',
      required: true
    },

    // Rounds that include this entry
    rounds: {
      collection: 'Round',
      via: 'entries'
    },

    // Groups that include this entry
    groups: {
      collection: 'EntryGroup',
      via: 'entries',
      dominant: true
    }

  }

};

EntryGroup.js

module.exports = {

  attributes: {

    // The participant that owns this group
    participation: {
      model: 'participation',
      required: true
    },

    // The round that this group is part of
    round: {
      model: 'round',
      required: true
    },

    // All of the other entries that are included in this group
    entries: {
      collection: 'Entry',
      via: 'groups'
    }

  }

};

Participation.js

module.exports = {

	attributes: {
	  // The user who is participating in a contest
    user: {
      model: 'User',
      required: true
    },
    // The contest this user is participating in
    contest: {
      model: 'Contest',
      required: true
    },
    // This user's entry into the contest
    entry: {
      model: 'Entry'
    },

    // This user's groups for this contest, one per round, contains other entries they get to see and vote on
    groups: {
      collection: 'EntryGroup',
      via: 'participation'
    }
    
	}
};

Round.js

module.exports = {

	attributes: {

    // The contest this round is part of
    contest: {
      model: 'Contest',
      required: true
    },

    // One group per participant/entry in this round
    groups: {
      collection: 'EntryGroup',
      via: 'round'
    },

    // All of the entries in this round
    entries: {
      collection: 'Entry',
      via: 'rounds',
      dominant: true
    }
    
	}

};