Relationships

Relationship

Currently supported relationships are:

• One-to-many
• One-to-one

One-to-Many

A Player has many Items.

In the following example, a player has many items

YamlJsonYaml (explicit)Json (explicit)

Player:
  name: str
  items: Item[]
Item:
  name: str
  player_id: Player.id
  player: Player

{
    "Player": {
        "name": "str",
        "items": "Item[]"
    },
    "Item": {
        "name": "str",
        "player_id": "Player.id",
        "player": "Player"
    }
}

Player:
  name:
  type: str
  items:
    type: relationship
    relationship: Item
    relationship_list: true
Item:
  name:
    type: str
  player_id:
    type: foreign_key
    foreign_key: Player.id
  player:
    type: relationship
    relationship: Player

{
    "Player": {
        "name": {
            "type": "str"
        },
        "items": {
            "type": "relationship",
            "relationship": "Item",
            "relationship_list": true
        }
    },
    "Item": {
        "name": {
            "type": "str"
        },
        "player_id": {
            "type": "foreign_key",
            "foreign_key": "Player.id"
        },
        "player": {
            "type": "relationship",
            "relationship": "Player"
        }
    }
}

By specifying the player relationship from the Item entity, we made a Item->Player relationship where an Item is related to a single Player.

Because the Player entity don't have any relationship declared, there is no rules concerning the relationship between Player->Item.

Note

As you can see, you can declare a items relationship in the Player resource to make the relationship usable from the Player entity.

This is fully optional and it don't do anything about the real relationship between Player and Item because evrything is set in the Item resource, but it allow the Player resource to display the linked Items resources.

Then, one Item belongs to one Player entity and one Player can have multiple Item entities. This is a One to Many relationship.

One to One

In the following example, a player has one bank account and a bank has many accounts.

YamlJsonYaml (explicit)Json (explicit)

Player:
  name: str
  account: BankAccount
Bank:
  name: str
BankAccount:
  bank_id: Bank.id
  bank: Bank
  player_id!: Player.id
  player: Player

{
    "Player": {
        "name": "str",
        "account": "BankAccount"
    },
    "Bank": {
        "name": "str"
    },
    "BankAccount": {
        "bank_id": "Bank.id",
        "bank": "Bank",
        "player_id!": "Player.id",
        "player": "Player"
    }
}

Player:
  name:
    type: str
  account:
    type: relationship
    relationship: BankAccount
Bank:
  name: str
BankAccount:
  bank_id:
    type: foreign_key
    foreign_key: Bank.id
  bank:
    type: relationship
    relationship: Bank
  player_id:
    type: foreign_key
    foreign_key: Player.id
    unique: true
  player:
    type: relationship
    relationship: Player

{
    "Player": {
        "name": {
            "type": "str"
        },
        "account": {
            "type": "relationship",
            "relationship": "BankAccount"
        }
    },
    "Bank": {
        "name": "str"
    },
    "BankAccount": {
        "bank_id": {
            "type": "foreign_key",
            "foreign_key": "Bank.id"
        },
        "bank": {
            "type": "relationship",
            "relationship": "Bank"
        },
        "player_id": {
            "type": "foreign_key",
            "foreign_key": "Player.id",
            "unique": true
        },
        "player": {
            "type": "relationship",
            "relationship": "Player"
        }
    }
}

By specifying the player relationship from the BankAccount entity, we made a BankAccount->Player relationship where a BankAccount is related to a single Player.

Because we also specify the player_id to be unique, The relationship to a player id can only exists once. Then a Player can have only one BankAccount.

Note

As you can see, you can declare a account relationship in the Player resource to make the relationship usable from the Player entity.

This is fully optional and it don't do anything about the real relationship between Player and BankAccount because evrything is set in the BankAccount resource, but it allow the Player resource to display the linked BankAccount resource.

Then, one Player has one BankAccount entity and one BankAccount is related to a single Player. This is a One to One relationship.

Known issues

• Currently you MUST specify a foreign key and a relationship attribute to make it work correctly.