GeneratesUniqueKey.md

GeneratesUniqueKey

Requires: HasAttributes.

method	type	description
setKey	new	Defines a unique _key property on the model.
getAttributes	extends	Ensures the _key property is not included in the attributes.
fill(...args)	extends	Calls the setKey method.

This mixin is not included by default

You can add it to your models like this.

import { Model as BaseModel, mix, GeneratesUniqueKey } from 'javel'

export default class Model extends mix(BaseModel).with(GeneratesUniqueKey) {
    ///
}

Generates unique keys

This mixin simply ensures there is always a unique _key property on your models. If a primaryKey() is available on the model, it will be used for the _key, otherwise a unique _key will be generated.

let articleA = await Article.find(1)    // => articleA._key === 1
let articleB = new Article()            // => articleB._key === 'new_0'

Once assigned the unique key does not change, even if a primary key is now avaialble.

let article = new Article()     // => article._key === 'new_0'
await article.persist()         // => article._key === 'new_0' && article.id === 1

This mixin is particularly useful when frameworks require you to provide a unique key on a model that hasn't been persisted yet. For example with Vue.js you could use :key="article._key".