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Defining relations

To use relations you must extend BaseModel class and add static relations property

import { BaseModel } from 'mobx-model';

class Post extends BaseModel
  static relations = [
    {
      type: 'hasMany',
      relatedModel: 'Comments'
    }
  ]
end

Relation config options

Note that if config option has a default it can be ommitted when declaring relations. Note that defaults are dynamic, so that you can incrementally override defautls as you need.

option	type	default	description
`type`	`string`		Can be `hasOne` or `hasMany`. An observable property defined by `propertyName` will be added to instance of model. If relation is `hasMany` an observable array will be added
`relatedModel`	`string`		Name of the model that will be supplied to `getModel` method to get related model class. We need this due to circular dependency problem when models refer to each other
`propertyName`	`string`	`relatedModel` with lowercased first letter for `hasOne` and is further pluralized for `hasMany`	Name of the property that will be set on model instance. For example if model is `Post` and `relatedModel` is `BestComment` then when relation is `hasOne` propertyName defaults to `bestComment`. When relation is `hasMany` it defaults to `bestComments` and can be later accessed with `post.bestComments`
`jsonKey`	`string`	uderscored `propertyName`	Is used to get relation json from provided model json. When `propertyName` is `bestComments` relation json by default is expected to be under `best_comments` key, and when `propertyName` is `bestComment` then it defaults to `best_comment`
`topLevelJsonKey`	`string`	tableized `propertyName`	Is used to get relation json from normalized array of objects in top level. if `propertyName` is `bestComments` than by default top level json must have `best_comments` key that is an array of objects
`foreignKey`	`string`	foreign key derived from `propertyName`	Used to look up relation ids in model json, that later will be used to find relation json in top level defined by `topLevelJsonKey`. If `propertyName` is `bestComment` and relation type is `hasOne` then `foreignKey` defaults to `best_comment_id`. If `propertyName` is `bestComments` and relation type is `hasMany` then `foreignKey` defaults to `best_comment_ids`
`setMethodName`	`string`	`set` + singularized `propertyName` with uppercased first letter	Name of the instance method to set related model, for `Post` that `hasMany` `Comment` it will default to `setComment`
`removeMethodName`	`string`	`remove` + singularized `propertyName` with uppercased first letter	Name of the instance method to remove related model, for `Post` that `hasMany` `Comment` it will default to `removeComment`
`reverseRelation`	`boolean` or `object`	`false`	If set to true or to an object then related model will have a property defined by `reverseRelation.propertyName` be set to this model instance. E.g. `Post` that `hasMany` `Comment` and `reverseRelation: true` will make `comment.post` available if `Post` relation is also set for `Comment` as `hasOne` relation

Reverse relation config options

option	type	default	description
`onDestroy`	`string`	`removeSelf`	Can be `removeSelf` or `destroyRelation`. Defines what needs to be done when relation is destroyed. When option is `removeSelf` this model will be removed from reverse relation, e.g. a comment will be removed from list of comments for a post. When it is set to `destroyRelation` then related model will be destroyed when this model is destroyed, e.g. when deleting a post we can delete all related comments.
`propertyName`	`string`	this model's name with lowercased first letter	{roperty name to set or remove on reverse relation. If `Post` has `Comment` then defaulP `reverseRelation.propertyName` will be `post`. Note that it should be singular even for `hasMany` relations
`setMethodName`	`string`	`set` + `reverseRelation.propertyName` with uppercased first letter	Instance method name on related model to set reverse relation. For `Post` that `hasMany` `Comment` it will default to `setPost`
`removeMethodName`	`string`	`remove` + `reverseRelation.propertyName` with uppercased first letter	Instance method name on related model to remove reverse relation. For `Post` that `hasMany` `Comment` it will default to `removePost`