蒸氣2，一對多關係

Question

您是否有任何關於如何使用Vapor 2建立一對多關係的例子？ 有一些如何做到這一點的例子，但他們使用舊版本的Vapor。

謝謝你的所有建議。

Answer 1

我找到了解決辦法。這裏有一個車主擁有很多車的簡單例子，可能會對某人有所幫助。

擁有者：

final class Owner: Model { 
    static let idKey = "id" 
    static let nameKey = "name" 
    static let carsKey = "cars" 

    var name: String 
    let storage = Storage() 

    var cars: Children<Owner, Car> { 
     return children() 
    } 


    init(name: String) { 
     self.name = name 
    } 

    init(row: Row) throws { 
     name = try row.get(Owner.nameKey) 
    } 

    func makeRow() throws -> Row { 
     var row = Row() 
     try row.set(Owner.nameKey, name) 
     return row 
    } 
} 

extension Owner: Preparation { 

    static func prepare(_ database: Database) throws { 
     try database.create(self) { builder in 
      builder.id() 
      builder.string(Owner.nameKey) 
     } 
    } 

    static func revert(_ database: Database) throws { 
     try database.delete(self) 
    } 
} 

extension Owner: JSONConvertible { 

    convenience init(json: JSON) throws { 
     try self.init(
      name: json.get(Owner.nameKey) 
     ) 
    } 

    func makeJSON() throws -> JSON { 
     var json = JSON() 
     try json.set(Owner.idKey, id) 
     try json.set(Owner.nameKey, name) 
     try json.set(Owner.carsKey, try cars.all()) 
     return json 
    } 
} 

extension Owner: ResponseRepresentable { } 

extension Owner: Updateable { 
    public static var updateableKeys: [UpdateableKey<Owner>] { 
     return [ 
      UpdateableKey(Owner.nameKey, String.self) { owner, text in 
       owner.name = name 
      } 
     ] 
    } 
} 

汽車：

final class Car: Model { 
    static let idKey = "id" 
    static let makeKey = "make" 
    static let modelKey = "model" 
    static let ownerIdKey = "owner_id" 

    var make: String 
    var model: String 
    var ownerId: Identifier 
    let storage = Storage() 

    var owner: Parent<Car, Owner> { 
     return parent(id: ownerId) 
    } 

    init(make: String, model: String, ownerId: Identifier) { 
     self.make = make 
     self.model = model 
     self.ownerId = ownerId 
    } 

    init(row: Row) throws { 
     make = try row.get(Car.makeKey) 
     model = try row.get(Car.modelKey) 
     ownerId = try row.get(Car.ownerIdKey) 
    } 

    func makeRow() throws -> Row { 
     var row = Row() 
     try row.set(Car.makeKey, make) 
     try row.set(Car.modelKey, model) 
     try row.set(Car.ownerIdKey, ownerId) 
     return row 
    } 
} 

extension Car: JSONConvertible { 

    convenience init(json: JSON) throws { 
     try self.init(
      make: json.get(Car.makeKey), 
      model: json.get(Car.modelKey), 
      ownerId: json.get(Car.ownerIdKey) 
     ) 
    } 

    func makeJSON() throws -> JSON { 
     var json = JSON() 
     try json.set(Car.idKey, id) 
     try json.set(Car.makeKey, make) 
     try json.set(Car.modelKey, model) 
     try json.set(Car.ownerIdKey, ownerId) 
     return json 
    } 
} 

extension Car: ResponseRepresentable {} 

extension Car: Preparation { 

    static func prepare(_ database: Database) throws { 
     try database.create(self) { builder in 
      builder.id() 
      builder.string(Car.makeKey) 
      builder.string(Car.modelKey) 
      builder.foreignId(for: Owner.self) 
     } 
    } 

    static func revert(_ database: Database) throws { 
     try database.delete(self) 
    } 
} 

extension Car: Updateable { 
    public static var updateableKeys: [UpdateableKey<Car>] { 
     return [ 
      UpdateableKey(Car.makeKey, String.self) { car, make in 
       car.make = make 
      } 
     ] 
    } 
}