Documentation

Generates a data constructor for an entity

data Post = Post { _ostId     :: Key
                 , _ostName   :: Text
                 , _ostUserId :: Key } deriving (Show, Read, Generic)

Generates a fromRow instance for a entity.

instance FromRow Post where
fromRow = Post <$> field <*> field <*> field

fromRowInstance takes a name of the entity and a list of [a], which is just used to count how many fields does the entity have - nothing else. It generates something similar shown in a code snippet above - a working FromRow instance for that datatype.

Generates field optics for all entities

Generates field optics for a column

name :: (FieldOptic "username" fun inType outType inVal outVal) => PolyOptic fun inType outType inVal outVal
name = fieldOpticProxy (Proxy :: Proxy "username")

Applies basic constraint depending on sql constraint If columns is marked as primary or unique, add the Unique haskell datatype

Generates a table field instance for a column

instance TableField Post "user_id" where
  type TableFieldType Post "user_id" = Key
  tableFieldLens = ostUserId

Generates required table field instances for all entities

Generates final type for the sql column

Generates initial accessor for the table

allPosts = allRows (Proxy :: Proxy "post")

Generates foreign key optics

Generates foreign key optic

author :: ForeignKeyLensProxy (Proxy "blog_post_author_fkey" -> o) => o
author = foreignKeyLens @"blog_post_author_fkey"

Generates virtual table optics

Generates virtual table optic

posts :: VirtualTable "blog_post_author_fkey" res
   => Getter' (Entity ('FromDb c) (ForeignKeyTo "blog_post_author_fkey")) res
posts = virtualTableLensProxy (Proxy :: Proxy "blog_post_author_fkey")

Generates all constraint declarations from the ParseContext

Generates unique key constraint instance

instance UniqueConstraint "blog_user_pkey" where
   type UniqueTable "blog_user_pkey" = User
   type UniqueFields "blog_user_pkey" = '["id"]

Generates primary key instance

instance PrimaryKeyConstraint "blog_user_pkey"

Generates foreign key instance

instance ForeignKeyConstraint "blog_post_author_fkey" where
type ForeignKeyFrom "blog_post_author_fkey" = Post
type ForeignKeyFromFields "blog_post_author_fkey" = '["author"]
type ForeignKeyTo "blog_post_author_fkey" = User
type ForeignKeyToFields "blog_post_author_fkey" = '["id"]

Generates a table instance for an entity from a ParseContext

instance Table Post where
    type TableName Post = "blog_post"
    type TableFields Post = ["id", "name", "author"]
    type TableConstraints Post = '[]
    type TablePrimaryKey Post = 'Nothing
    type TableRequiredFields Post = ['DynamicDefault 'id, 'Required "name", 'Required "author"]

Generates a empty entity

newPost :: Entity ('Fresh ['DynamicDefault "id", 'Required "name", 'Required "author"])
newPost = Entity (Post 1 "" 1)

Applies Required constraint to list of columns

Applies DynamicDefault constraint to a list of columns

Modifies column type depending on column constraints

Generates coerce body. See NullValue why this is needed

Generated the value representing the schema that can be applied to the database