gimme example to create model relations on StrongLoop

Question

here i want to create model relations on StrongLoop. I have this kind of scenario:

1. Category:
   • id:1
   • name:history
2. Book
   • id:1
   • id_category:1
   • title:american-hustle
   • id_publisher:1
   • --------------------------
   • id:2
   • id_category:1
   • title:american-hustle2
   • id_publisher:2
3. Publisher
   • id:1
   • name:Publisher-1
   • --------------------------
   • id:2
   • name:Publisher-2

how can i create model relations like that? Thanks.

Answer 1

You should be able to find what you need at:

http://strongloop.com/strongblog/defining-and-mapping-data-relations-with-loopback-connected-models/

Basically,

// 1-many
Category.hasMany(Book, {as: 'books', foreignKey: 'id_category'});
Publisher.hasMany(Book, {as: 'books', foreignKey: 'id_publisher'});

// belongsTo
Book.belongsTo(Category, {as: 'category', foreignKey: 'id_category'});
Book.belongsTo(Publisher, {as: 'publisher', foreignKey: 'id_publisher'}); 

Depending on how you want to navigate the model relations, you can define one direction or both.