Factories and Models

Model is representing a single resource in terms of RESTful APIs. It lists properties associated with business model and contains methods that may manipulate model’s state. Commonly Models structure has 1:1 mapping with persistent storage.

Collection of models is managed by Factories. Basically, two main functions of a factory is to create a new Model instance or retrieve collection of models from some storage.

Cool thing in models declaration in Dominion framework is ability to specify extra features for each Model’s property. It includes: data validation, input modification, output modification and documentation info. More about this you can read on Properties page.

By default Factories prototype and Models prototype contain the most common manipulations you will need in a project. And of course, you can extend or overwrite it using factory: and instance: properties in a Factory declaration.

Writing a factory

Files containing factory declaration should export an object with model’s properties and prototypes for models factories and models instances.

Factory declaration object has following properties:

Name	Description
name	String, required. Model’s name. Good practice is to keep model’s name always in plural to avoid ambiguity.
repository	Object, optional. Repository object the model is linked to.
properties	Object, required. Object containing model’s properties. Object keys will be properties’ names, values - properties validators.
factory	Object, optional. Object containing functions that will be used to extend model’s factory prototype.
instance	Object, optional. Object containing functions that will be used to extend model’s prototype.

Code example

const Errors = require("@dominion-framework/dominion/core/errors");
const Property = require("@dominion-framework/dominion/core/property");

const UsersRepository = require("./repository");


module.exports = {

    name: "Users",

    repository: UsersRepository, 

    properties: {
        id: Property.id(),
        phoneNumber: Property.number().min(1e11).max(1e12-1),
        email: Property.string().pattern(/\S+@\S\(.\S)+/).max(100),
        passwordHash: Property.string().max(255).private(),
        passwordSalt: Property.string().max(255).private(),
        creationTime: Property.date().private(),
        modificationTime: Property.date().private()
    },

    factory: {

        getActiveUsers(limit = 6, offset = 0) {
            return this.repo.getActiveUsers(limit, offset)
                .then(users => Promise.all(users.map(mix => this.new(mix, false))));
        }

    },

    instance: {

        checkPassword(password) {
            if (this.passwordHash === createHash(password, this.passwordSalt)) {
                return this;
            } else {
                throw new Errors.Unauthorized("Incorrect credentials");
            }
        },

        setPassword(password) {
            let [passwordHash, passwordSalt] = hash(password);
            this.populate({passwordHash, passwordSalt});
            return this;
        }

    }
};