157 lines
4.5 KiB
Haskell
157 lines
4.5 KiB
Haskell
module PostgREST.Types where
|
|
import Data.Text
|
|
import Data.Tree
|
|
import qualified Data.ByteString.Lazy as BL
|
|
import qualified Data.ByteString as BS
|
|
import qualified Data.Vector as V
|
|
import Data.Aeson
|
|
|
|
data DbStructure = DbStructure {
|
|
dbTables :: [Table]
|
|
, dbColumns :: [Column]
|
|
, dbRelations :: [Relation]
|
|
, dbPrimaryKeys :: [PrimaryKey]
|
|
} deriving (Show, Eq)
|
|
|
|
type Schema = Text
|
|
type TableName = Text
|
|
type SqlQuery = Text
|
|
type SqlFragment = Text
|
|
type RequestBody = BL.ByteString
|
|
|
|
data Table = Table {
|
|
tableSchema :: Schema
|
|
, tableName :: TableName
|
|
, tableInsertable :: Bool
|
|
} deriving (Show, Ord)
|
|
|
|
data ForeignKey = ForeignKey { fkCol :: Column } deriving (Show, Eq, Ord)
|
|
|
|
data Column =
|
|
Column {
|
|
colTable :: Table
|
|
, colName :: Text
|
|
, colPosition :: Int
|
|
, colNullable :: Bool
|
|
, colType :: Text
|
|
, colUpdatable :: Bool
|
|
, colMaxLen :: Maybe Int
|
|
, colPrecision :: Maybe Int
|
|
, colDefault :: Maybe Text
|
|
, colEnum :: [Text]
|
|
, colFK :: Maybe ForeignKey
|
|
}
|
|
| Star { colTable :: Table }
|
|
deriving (Show, Ord)
|
|
|
|
type Synonym = (Column,Column)
|
|
|
|
data PrimaryKey = PrimaryKey {
|
|
pkTable :: Table
|
|
, pkName :: Text
|
|
} deriving (Show, Eq)
|
|
|
|
data OrderDirection = OrderAsc | OrderDesc deriving (Eq)
|
|
instance Show OrderDirection where
|
|
show OrderAsc = "asc"
|
|
show OrderDesc = "desc"
|
|
|
|
data OrderNulls = OrderNullsFirst | OrderNullsLast deriving (Eq)
|
|
instance Show OrderNulls where
|
|
show OrderNullsFirst = "nulls first"
|
|
show OrderNullsLast = "nulls last"
|
|
|
|
data OrderTerm = OrderTerm {
|
|
otTerm :: Text
|
|
, otDirection :: OrderDirection
|
|
, otNullOrder :: Maybe OrderNulls
|
|
} deriving (Show, Eq)
|
|
|
|
data QualifiedIdentifier = QualifiedIdentifier {
|
|
qiSchema :: Schema
|
|
, qiName :: TableName
|
|
} deriving (Show, Eq)
|
|
|
|
|
|
data RelationType = Child | Parent | Many deriving (Show, Eq)
|
|
data Relation = Relation {
|
|
relTable :: Table
|
|
, relColumns :: [Column]
|
|
, relFTable :: Table
|
|
, relFColumns :: [Column]
|
|
, relType :: RelationType
|
|
, relLTable :: Maybe Table
|
|
, relLCols1 :: Maybe [Column]
|
|
, relLCols2 :: Maybe [Column]
|
|
} deriving (Show, Eq)
|
|
|
|
-- | An array of JSON objects that has been verified to have
|
|
-- the same keys in every object
|
|
newtype UniformObjects = UniformObjects (V.Vector Object)
|
|
deriving (Show, Eq)
|
|
|
|
-- | When Hasql supports the COPY command then we can
|
|
-- have a special payload just for CSV, but until
|
|
-- then CSV is converted to a JSON array.
|
|
data Payload = PayloadJSON UniformObjects
|
|
| PayloadParseError BS.ByteString
|
|
deriving (Show, Eq)
|
|
|
|
type Operator = Text
|
|
data FValue = VText Text | VForeignKey QualifiedIdentifier ForeignKey deriving (Show, Eq)
|
|
type FieldName = Text
|
|
type JsonPath = [Text]
|
|
type Field = (FieldName, Maybe JsonPath)
|
|
type Cast = Text
|
|
type NodeName = Text
|
|
type SelectItem = (Field, Maybe Cast)
|
|
type Path = [Text]
|
|
data ReadQuery = Select { select::[SelectItem], from::[Text], flt_::[Filter], order::Maybe [OrderTerm] } deriving (Show, Eq)
|
|
data MutateQuery = Insert { in_::Text, qPayload::Payload }
|
|
| Delete { in_::Text, where_::[Filter] }
|
|
| Update { in_::Text, qPayload::Payload, where_::[Filter] } deriving (Show, Eq)
|
|
data Filter = Filter {field::Field, operator::Operator, value::FValue} deriving (Show, Eq)
|
|
type ReadNode = (ReadQuery, (NodeName, Maybe Relation))
|
|
type ReadRequest = Tree ReadNode
|
|
type MutateRequest = MutateQuery
|
|
data DbRequest = DbRead ReadRequest | DbMutate MutateRequest
|
|
|
|
|
|
instance ToJSON Column where
|
|
toJSON c = object [
|
|
"schema" .= tableSchema t
|
|
, "name" .= colName c
|
|
, "position" .= colPosition c
|
|
, "nullable" .= colNullable c
|
|
, "type" .= colType c
|
|
, "updatable" .= colUpdatable c
|
|
, "maxLen" .= colMaxLen c
|
|
, "precision" .= colPrecision c
|
|
, "references".= colFK c
|
|
, "default" .= colDefault c
|
|
, "enum" .= colEnum c ]
|
|
where
|
|
t = colTable c
|
|
|
|
instance ToJSON ForeignKey where
|
|
toJSON fk = object [
|
|
"schema" .= tableSchema t
|
|
, "table" .= tableName t
|
|
, "column" .= colName c ]
|
|
where
|
|
c = fkCol fk
|
|
t = colTable c
|
|
|
|
instance ToJSON Table where
|
|
toJSON v = object [
|
|
"schema" .= tableSchema v
|
|
, "name" .= tableName v
|
|
, "insertable" .= tableInsertable v ]
|
|
|
|
instance Eq Table where
|
|
Table{tableSchema=s1,tableName=n1} == Table{tableSchema=s2,tableName=n2} = s1 == s2 && n1 == n2
|
|
|
|
instance Eq Column where
|
|
Column{colTable=t1,colName=n1} == Column{colTable=t2,colName=n2} = t1 == t2 && n1 == n2
|
|
_ == _ = False
|