Custom methods

Custom methods can be added to entities instances through their Schemas.

schema.methods.<methodName> = function(){ ... }

Make sure not to use arrow function as you would lose the scope of the entity instance.

const blogPostSchema = new Schema({ title: {} });
// Custom method to retrieve all children Text entities
blogPostSchema.methods.texts = function getTexts() {
// the scope (this) is the entity instance
const query = this.model('Text')
.query()
.hasAncestor(this.entityKey);
return query.run();
};
// In your Controller
// You can then call it on an entity instance of BlogPost
const BlogPost = require('../models/blogpost.model');
BlogPost.get(123)
.then((blogEntity) => {
blogEntity.texts()
.then((response) => {
const texts = response[0].entities;
});
});

Note how entities instances can access other models through entity.model('MyModel'). Denormalization can then easily be done with a custom method:

// Add custom "profilePict()" method on the User Schema
userSchema.methods.profilePicture = function profilePicture() {
// Any type of query can be done here
return this.model('Image').get(this.imageIdx);
};
// In your controller
const User = require('../models/user.model');
const user = new User({ name: 'John', imageIdx: 1234 });
user.profilePicture()
.then((imageEntity) => {
user.profilePicture = imageEntity.url;
user.save()
.then(() { ... });
});
// Or with a callback
userSchema.methods.profilePict = function(cb) {
return this.model('Image').get(this.imageIdx, cb);
};
...
const user = new User({ name:'John', imageIdx:1234 });
// Call custom Method 'getImage'
user.profilePict(function onProfilePict(err, imageEntity) {
user.profilePict = imageEntity.url;
user.save().then(() { ... });
});