Relationships

Modelarium handles relationships pretty automatically, making seeds and factories work trivially and providing an easy way to pick relationships in forms.

Declaring relationships

Declaring relationships is done through simple directives. This is 100% compatible with LighthousePHP and follows the same structure of Eloquent

One-to-one

Example of a one-to-one relationship:

type User {
  id: ID!
  phone: Phone! @hasOne
}

type Phone {
  id: ID!
  user: User!
    @belongsTo
    @migrationForeign(onDelete: "cascade", onUpdate: "cascade")
}

One-to-many

type Post {
  id: ID!
  comments: [Comment!]! @hasMany
}

type Comment {
  id: ID!
  post: Post!
    @belongsTo
    @migrationForeign(onDelete: "cascade", onUpdate: "cascade")
}

Many-to-many

Many-to-many relationships will create an auxiliary table.

type User {
  id: ID!
  roles: [Role!]! @belongsToMany
}

type Role {
  id: ID!
  users: [User!]! @belongsToMany
}

Polymorphic one-to-one

type Post {
  id: ID!
  name: String!
  image: Image! @morphOne
}

type User {
  id: ID!
  name: String!
  image: Image @morphOne
}

union Imageable = Post | User

type Image {
  id: ID!
  url: String!
  imageable: Imageable! @morphTo
}

Polymorphic one-to-many

type User {
  id: ID!
  name: String!
  images: [Image!] @morphMany
}

type Post {
  images: [Image!] @morphMany
}

type Image {
  id: ID!
  imageable: Imageable! @morphTo
}

union Imageable = Post | User

Polymorphic many-to-many

type Post {
  id: ID!
  name: String!
  tags: [Tag!] @morphToMany
}

type Video {
  id: ID!
  name: String!
  tags: [Tag!] @morphToMany
}

type Tag {
  id: ID!
  name: String!
  taggable: [Taggable!]! @morphedByMany
}

union Taggable = Video | Post

Frontend implementation

Single selector

You can use the Selector component to automatically pick relationships in forms. This works well if the number of relationships is reasonably small (in the tens), since it uses <select> and loads data just once.

This is fully automated by Modelarium, and as long as you declare the relationship and a @modelFillable directive it will be work as expected. If you need to customize the

Autocomplete

TODO

Multiple

TODO

Customizing relationship data types

Relationship datatypes are generated automatically for you. They all implement the Datatype_relationship class through a special factory.

When parsing GraphQL, Modelarium creates a new data type for each relationship with this name: relationship[:inverse?]:[mode]:[source]:[target]. Example: relationship:inverse:1N:post:user.

• [:inverse?] if present, this means it’s an inverse relationship, otherwise it’s a direct relationship. We define a direct relationship as the one going from the original model (BelongsTo) to its target (HasMany) and the inverse as its opposite. For example, if a User can make Posts, User -> Post is the direct relationship and Post -> User is the inverse relationship.

• [mode] the cardinality of relationship. The possible types are declared as constants in RelationshipFactory: RELATIONSHIP_ONE_TO_ONE, RELATIONSHIP_ONE_TO_MANY, RELATIONSHIP_MANY_TO_MANY, MORPH_ONE_TO_ONE, MORPH_ONE_TO_MANY, MORPH_MANY_TO_MANY.