wireform-thrift-0.1.0.0: src/Thrift/Schema.hs

{-# LANGUAGE BangPatterns #-}

{- | Thrift schema AST — a complete representation of Thrift IDL constructs.

Covers base types, containers, structs, unions, exceptions, enums,
typedefs, constants, and services.
-}
module Thrift.Schema (
  -- * Top-level schema
  ThriftSchema (..),

  -- * Types
  ThriftType (..),

  -- * Struct / Union / Exception
  ThriftStruct (..),
  StructKind (..),
  ThriftField (..),
  Requiredness (..),

  -- * Enum
  ThriftEnum (..),

  -- * Service
  ThriftService (..),
  ThriftMethod (..),

  -- * Const
  ThriftConst (..),
  ThriftConstValue (..),

  -- * Typedef
  ThriftTypedef (..),
) where

import Data.Int (Int32, Int64)
import Data.Text (Text)
import Data.Vector (Vector)


--------------------------------------------------------------------------------
-- Requiredness
--------------------------------------------------------------------------------

-- | Field requiredness as specified in the Thrift IDL.
data Requiredness
  = -- | The field must be present.
    Required
  | -- | The field may be absent.
    Optional
  | -- | Requiredness not specified (Thrift default behavior).
    Default
  deriving stock (Show, Eq, Ord, Enum, Bounded)


--------------------------------------------------------------------------------
-- Thrift types
--------------------------------------------------------------------------------

-- | All types expressible in Thrift IDL.
data ThriftType
  = TBool
  | TByte
  | TI16
  | TI32
  | TI64
  | TDouble
  | TString
  | TBinary
  | TUUID
  | TStruct !Text
  | TEnum !Text
  | TTypedef !Text
  | TList !ThriftType
  | TSet !ThriftType
  | TMap !ThriftType !ThriftType
  deriving stock (Show, Eq, Ord)


--------------------------------------------------------------------------------
-- Fields
--------------------------------------------------------------------------------

-- | A single field in a struct, union, or exception.
data ThriftField = ThriftField
  { tfFieldId :: {-# UNPACK #-} !Int32
  , tfFieldName :: !Text
  , tfFieldType :: !ThriftType
  , tfRequiredness :: !Requiredness
  , tfDefault :: !(Maybe ThriftConstValue)
  , tfAnnotations :: !(Vector (Text, Text))
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Struct / Union / Exception
--------------------------------------------------------------------------------

-- | Struct kind tag.
data StructKind = StructNormal | StructUnion | StructException
  deriving stock (Show, Eq, Ord, Enum, Bounded)


-- | A Thrift struct, union, or exception.
data ThriftStruct = ThriftStruct
  { tsName :: !Text
  , tsKind :: !StructKind
  , tsFields :: ![ThriftField]
  , tsAnnotations :: !(Vector (Text, Text))
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Enum
--------------------------------------------------------------------------------

-- | A Thrift enum definition.
data ThriftEnum = ThriftEnum
  { teName :: !Text
  , teValues :: ![(Text, Int32)]
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Typedef
--------------------------------------------------------------------------------

-- | A Thrift typedef.
data ThriftTypedef = ThriftTypedef
  { ttName :: !Text
  , ttType :: !ThriftType
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Constants
--------------------------------------------------------------------------------

-- | Constant values in the Thrift IDL.
data ThriftConstValue
  = TCVInt {-# UNPACK #-} !Int64
  | TCVDouble {-# UNPACK #-} !Double
  | TCVString !Text
  | TCVBool !Bool
  | TCVList ![ThriftConstValue]
  | TCVMap ![(ThriftConstValue, ThriftConstValue)]
  | TCVIdent !Text
  deriving stock (Show, Eq)


-- | A top-level constant definition.
data ThriftConst = ThriftConst
  { tcName :: !Text
  , tcType :: !ThriftType
  , tcValue :: !ThriftConstValue
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Service
--------------------------------------------------------------------------------

-- | A single method in a Thrift service.
data ThriftMethod = ThriftMethod
  { tmName :: !Text
  , tmReturnType :: !(Maybe ThriftType)
  , tmParams :: ![ThriftField]
  , tmThrows :: ![ThriftField]
  , tmOneway :: !Bool
  }
  deriving stock (Show, Eq)


-- | A Thrift service definition.
data ThriftService = ThriftService
  { tsvName :: !Text
  , tsvExtends :: !(Maybe Text)
  , tsvMethods :: ![ThriftMethod]
  }
  deriving stock (Show, Eq)


--------------------------------------------------------------------------------
-- Top-level schema
--------------------------------------------------------------------------------

-- | A complete Thrift schema (one .thrift file).
data ThriftSchema = ThriftSchema
  { tsStructs :: ![ThriftStruct]
  , tsEnums :: ![ThriftEnum]
  , tsTypedefs :: ![ThriftTypedef]
  , tsConsts :: ![ThriftConst]
  , tsServices :: ![ThriftService]
  }
  deriving stock (Show, Eq)