module Database.Persist.Postgresql
( withPostgresqlPool
, withPostgresqlConn
, createPostgresqlPool
, createPostgresqlPoolModified
, module Database.Persist.Sql
, ConnectionString
, PostgresConf (..)
, openSimpleConn
, tableName
, fieldName
, mockMigration
) where
import Database.Persist.Sql
import Database.Persist.Sql.Util (dbIdColumnsEsc)
import Data.Fixed (Pico)
import qualified Database.PostgreSQL.Simple as PG
import qualified Database.PostgreSQL.Simple.TypeInfo as PG
import qualified Database.PostgreSQL.Simple.TypeInfo.Static as PS
import qualified Database.PostgreSQL.Simple.Internal as PG
import qualified Database.PostgreSQL.Simple.ToField as PGTF
import qualified Database.PostgreSQL.Simple.FromField as PGFF
import qualified Database.PostgreSQL.Simple.Types as PG
import Database.PostgreSQL.Simple.Ok (Ok (..))
import qualified Database.PostgreSQL.LibPQ as LibPQ
import Control.Monad.Trans.Resource
import Control.Exception (throw)
import Control.Monad.IO.Class (MonadIO (..))
import Data.Data
import Data.Typeable
import Data.IORef
import qualified Data.Map as Map
import Data.Maybe
import Data.Either (partitionEithers)
import Control.Arrow
import Data.List (find, sort, groupBy)
import Data.Function (on)
import Data.Conduit
import qualified Data.Conduit.List as CL
import Control.Monad.Logger (MonadLogger, runNoLoggingT)
import qualified Data.IntMap as I
import Data.ByteString (ByteString)
import qualified Data.ByteString.Char8 as B8
import qualified Data.Text as T
import qualified Data.Text.Encoding as T
import qualified Data.Text.IO as T
import qualified Blaze.ByteString.Builder.Char8 as BBB
import Data.Text (Text)
import Data.Aeson
import Data.Aeson.Types (modifyFailure)
import Control.Monad (forM)
import Control.Monad.Trans.Reader (runReaderT)
import Control.Monad.Trans.Writer (runWriterT)
import Data.Acquire (Acquire, mkAcquire, with)
import System.Environment (getEnvironment)
import Data.Int (Int64)
import Data.Monoid ((<>))
import Data.Time (utc, localTimeToUTC)
type ConnectionString = ByteString
withPostgresqlPool :: (MonadBaseControl IO m, MonadLogger m, MonadIO m)
=> ConnectionString
-> Int
-> (ConnectionPool -> m a)
-> m a
withPostgresqlPool ci = withSqlPool $ open' (const $ return ()) ci
createPostgresqlPool :: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
=> ConnectionString
-> Int
-> m ConnectionPool
createPostgresqlPool = createPostgresqlPoolModified (const $ return ())
createPostgresqlPoolModified
:: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
=> (PG.Connection -> IO ())
-> ConnectionString
-> Int
-> m ConnectionPool
createPostgresqlPoolModified modConn ci = createSqlPool $ open' modConn ci
withPostgresqlConn :: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
=> ConnectionString -> (SqlBackend -> m a) -> m a
withPostgresqlConn = withSqlConn . open' (const $ return ())
open' :: (PG.Connection -> IO ())
-> ConnectionString -> LogFunc -> IO SqlBackend
open' modConn cstr logFunc = do
conn <- PG.connectPostgreSQL cstr
modConn conn
openSimpleConn logFunc conn
openSimpleConn :: LogFunc -> PG.Connection -> IO SqlBackend
openSimpleConn logFunc conn = do
smap <- newIORef $ Map.empty
return SqlBackend
{ connPrepare = prepare' conn
, connStmtMap = smap
, connInsertSql = insertSql'
, connInsertManySql = Just insertManySql'
, connClose = PG.close conn
, connMigrateSql = migrate'
, connBegin = const $ PG.begin conn
, connCommit = const $ PG.commit conn
, connRollback = const $ PG.rollback conn
, connEscapeName = escape
, connNoLimit = "LIMIT ALL"
, connRDBMS = "postgresql"
, connLimitOffset = decorateSQLWithLimitOffset "LIMIT ALL"
, connLogFunc = logFunc
}
prepare' :: PG.Connection -> Text -> IO Statement
prepare' conn sql = do
let query = PG.Query (T.encodeUtf8 sql)
return Statement
{ stmtFinalize = return ()
, stmtReset = return ()
, stmtExecute = execute' conn query
, stmtQuery = withStmt' conn query
}
insertSql' :: EntityDef -> [PersistValue] -> InsertSqlResult
insertSql' ent vals =
let sql = T.concat
[ "INSERT INTO "
, escape $ entityDB ent
, if null (entityFields ent)
then " DEFAULT VALUES"
else T.concat
[ "("
, T.intercalate "," $ map (escape . fieldDB) $ entityFields ent
, ") VALUES("
, T.intercalate "," (map (const "?") $ entityFields ent)
, ")"
]
]
in case entityPrimary ent of
Just _pdef -> ISRManyKeys sql vals
Nothing -> ISRSingle (sql <> " RETURNING " <> escape (fieldDB (entityId ent)))
insertManySql' :: EntityDef -> [[PersistValue]] -> InsertSqlResult
insertManySql' ent valss =
let sql = T.concat
[ "INSERT INTO "
, escape (entityDB ent)
, "("
, T.intercalate "," $ map (escape . fieldDB) $ entityFields ent
, ") VALUES ("
, T.intercalate "),(" $ replicate (length valss) $ T.intercalate "," $ map (const "?") (entityFields ent)
, ") RETURNING "
, T.intercalate ", " $ dbIdColumnsEsc escape ent
]
in ISRSingle sql
execute' :: PG.Connection -> PG.Query -> [PersistValue] -> IO Int64
execute' conn query vals = PG.execute conn query (map P vals)
withStmt' :: MonadIO m
=> PG.Connection
-> PG.Query
-> [PersistValue]
-> Acquire (Source m [PersistValue])
withStmt' conn query vals =
pull `fmap` mkAcquire openS closeS
where
openS = do
rawquery <- PG.formatQuery conn query (map P vals)
(rt, rr, rc, ids) <- PG.withConnection conn $ \rawconn -> do
mret <- LibPQ.exec rawconn rawquery
case mret of
Nothing -> do
merr <- LibPQ.errorMessage rawconn
fail $ case merr of
Nothing -> "Postgresql.withStmt': unknown error"
Just e -> "Postgresql.withStmt': " ++ B8.unpack e
Just ret -> do
status <- LibPQ.resultStatus ret
case status of
LibPQ.TuplesOk -> return ()
_ -> PG.throwResultError "Postgresql.withStmt': bad result status " ret status
cols <- LibPQ.nfields ret
oids <- forM [0..cols1] $ \col -> fmap ((,) col) (LibPQ.ftype ret col)
rowRef <- newIORef (LibPQ.Row 0)
rowCount <- LibPQ.ntuples ret
return (ret, rowRef, rowCount, oids)
let getters
= map (\(col, oid) -> getGetter conn oid $ PG.Field rt col oid) ids
return (rt, rr, rc, getters)
closeS (ret, _, _, _) = LibPQ.unsafeFreeResult ret
pull x = do
y <- liftIO $ pullS x
case y of
Nothing -> return ()
Just z -> yield z >> pull x
pullS (ret, rowRef, rowCount, getters) = do
row <- atomicModifyIORef rowRef (\r -> (r+1, r))
if row == rowCount
then return Nothing
else fmap Just $ forM (zip getters [0..]) $ \(getter, col) -> do
mbs <- LibPQ.getvalue' ret row col
case mbs of
Nothing ->
return PersistNull
Just bs -> do
ok <- PGFF.runConversion (getter mbs) conn
bs `seq` case ok of
Errors (exc:_) -> throw exc
Errors [] -> error "Got an Errors, but no exceptions"
Ok v -> return v
newtype P = P PersistValue
instance PGTF.ToField P where
toField (P (PersistText t)) = PGTF.toField t
toField (P (PersistByteString bs)) = PGTF.toField (PG.Binary bs)
toField (P (PersistInt64 i)) = PGTF.toField i
toField (P (PersistDouble d)) = PGTF.toField d
toField (P (PersistRational r)) = PGTF.Plain $
BBB.fromString $
show (fromRational r :: Pico)
toField (P (PersistBool b)) = PGTF.toField b
toField (P (PersistDay d)) = PGTF.toField d
toField (P (PersistTimeOfDay t)) = PGTF.toField t
toField (P (PersistUTCTime t)) = PGTF.toField t
toField (P PersistNull) = PGTF.toField PG.Null
toField (P (PersistList l)) = PGTF.toField $ listToJSON l
toField (P (PersistMap m)) = PGTF.toField $ mapToJSON m
toField (P (PersistDbSpecific s)) = PGTF.toField (Unknown s)
toField (P (PersistObjectId _)) =
error "Refusing to serialize a PersistObjectId to a PostgreSQL value"
newtype Unknown = Unknown { unUnknown :: ByteString }
deriving (Eq, Show, Read, Ord, Typeable)
instance PGFF.FromField Unknown where
fromField f mdata =
case mdata of
Nothing -> PGFF.returnError PGFF.UnexpectedNull f "Database.Persist.Postgresql/PGFF.FromField Unknown"
Just dat -> return (Unknown dat)
instance PGTF.ToField Unknown where
toField (Unknown a) = PGTF.Escape a
type Getter a = PGFF.FieldParser a
convertPV :: PGFF.FromField a => (a -> b) -> Getter b
convertPV f = (fmap f .) . PGFF.fromField
builtinGetters :: I.IntMap (Getter PersistValue)
builtinGetters = I.fromList
[ (k PS.bool, convertPV PersistBool)
, (k PS.bytea, convertPV (PersistByteString . unBinary))
, (k PS.char, convertPV PersistText)
, (k PS.name, convertPV PersistText)
, (k PS.int8, convertPV PersistInt64)
, (k PS.int2, convertPV PersistInt64)
, (k PS.int4, convertPV PersistInt64)
, (k PS.text, convertPV PersistText)
, (k PS.xml, convertPV PersistText)
, (k PS.float4, convertPV PersistDouble)
, (k PS.float8, convertPV PersistDouble)
#if !MIN_VERSION_postgresql_simple(0,5,0)
, (k PS.abstime, convertPV PersistUTCTime)
, (k PS.reltime, convertPV PersistUTCTime)
#endif
, (k PS.money, convertPV PersistRational)
, (k PS.bpchar, convertPV PersistText)
, (k PS.varchar, convertPV PersistText)
, (k PS.date, convertPV PersistDay)
, (k PS.time, convertPV PersistTimeOfDay)
, (k PS.timestamp, convertPV (PersistUTCTime. localTimeToUTC utc))
, (k PS.timestamptz, convertPV PersistUTCTime)
, (k PS.bit, convertPV PersistInt64)
, (k PS.varbit, convertPV PersistInt64)
, (k PS.numeric, convertPV PersistRational)
, (k PS.void, \_ _ -> return PersistNull)
, (k PS.json, convertPV (PersistByteString . unUnknown))
, (k PS.jsonb, convertPV (PersistByteString . unUnknown))
, (k PS.unknown, convertPV (PersistByteString . unUnknown))
, (1000, listOf PersistBool)
, (1001, listOf (PersistByteString . unBinary))
, (1002, listOf PersistText)
, (1003, listOf PersistText)
, (1016, listOf PersistInt64)
, (1005, listOf PersistInt64)
, (1007, listOf PersistInt64)
, (1009, listOf PersistText)
, (143, listOf PersistText)
, (1021, listOf PersistDouble)
, (1022, listOf PersistDouble)
, (1023, listOf PersistUTCTime)
, (1024, listOf PersistUTCTime)
, (791, listOf PersistRational)
, (1014, listOf PersistText)
, (1015, listOf PersistText)
, (1182, listOf PersistDay)
, (1183, listOf PersistTimeOfDay)
, (1115, listOf PersistUTCTime)
, (1185, listOf PersistUTCTime)
, (1561, listOf PersistInt64)
, (1563, listOf PersistInt64)
, (1231, listOf PersistRational)
, (2951, listOf (PersistDbSpecific . unUnknown))
, (199, listOf (PersistByteString . unUnknown))
, (3807, listOf (PersistByteString . unUnknown))
]
where
k (PGFF.typoid -> i) = PG.oid2int i
listOf f = convertPV (PersistList . map (nullable f) . PG.fromPGArray)
where nullable = maybe PersistNull
getGetter :: PG.Connection -> PG.Oid -> Getter PersistValue
getGetter _conn oid
= fromMaybe defaultGetter $ I.lookup (PG.oid2int oid) builtinGetters
where defaultGetter = convertPV (PersistDbSpecific . unUnknown)
unBinary :: PG.Binary a -> a
unBinary (PG.Binary x) = x
doesTableExist :: (Text -> IO Statement)
-> DBName
-> IO Bool
doesTableExist getter (DBName name) = do
stmt <- getter sql
with (stmtQuery stmt vals) ($$ start)
where
sql = "SELECT COUNT(*) FROM pg_catalog.pg_tables WHERE schemaname != 'pg_catalog'"
<> " AND schemaname != 'information_schema' AND tablename=?"
vals = [PersistText name]
start = await >>= maybe (error "No results when checking doesTableExist") start'
start' [PersistInt64 0] = finish False
start' [PersistInt64 1] = finish True
start' res = error $ "doesTableExist returned unexpected result: " ++ show res
finish x = await >>= maybe (return x) (error "Too many rows returned in doesTableExist")
migrate' :: [EntityDef]
-> (Text -> IO Statement)
-> EntityDef
-> IO (Either [Text] [(Bool, Text)])
migrate' allDefs getter entity = fmap (fmap $ map showAlterDb) $ do
old <- getColumns getter entity
case partitionEithers old of
([], old'') -> do
exists <-
if null old
then doesTableExist getter name
else return True
return $ Right $ migrationText exists old''
(errs, _) -> return $ Left errs
where
name = entityDB entity
migrationText exists old'' =
if not exists
then createText newcols fdefs udspair
else let (acs, ats) = getAlters allDefs entity (newcols, udspair) old'
acs' = map (AlterColumn name) acs
ats' = map (AlterTable name) ats
in acs' ++ ats'
where
old' = partitionEithers old''
(newcols', udefs, fdefs) = mkColumns allDefs entity
newcols = filter (not . safeToRemove entity . cName) newcols'
udspair = map udToPair udefs
createText newcols fdefs udspair =
(addTable newcols entity) : uniques ++ references ++ foreignsAlt
where
uniques = flip concatMap udspair $ \(uname, ucols) ->
[AlterTable name $ AddUniqueConstraint uname ucols]
references = mapMaybe (\c@Column { cName=cname, cReference=Just (refTblName, _) } ->
getAddReference allDefs name refTblName cname (cReference c))
$ filter (isJust . cReference) newcols
foreignsAlt = flip map fdefs (\fdef ->
let (childfields, parentfields) = unzip (map (\((_,b),(_,d)) -> (b,d)) (foreignFields fdef))
in AlterColumn name (foreignRefTableDBName fdef, AddReference (foreignConstraintNameDBName fdef) childfields (map escape parentfields)))
addTable :: [Column] -> EntityDef -> AlterDB
addTable cols entity = AddTable $ T.concat
[ "CREATe TABLE "
, escape name
, "("
, idtxt
, if null cols then "" else ","
, T.intercalate "," $ map showColumn cols
, ")"
]
where
name = entityDB entity
idtxt = case entityPrimary entity of
Just pdef -> T.concat [" PRIMARY KEY (", T.intercalate "," $ map (escape . fieldDB) $ compositeFields pdef, ")"]
Nothing ->
let defText = defaultAttribute $ fieldAttrs $ entityId entity
sType = fieldSqlType $ entityId entity
in T.concat
[ escape $ fieldDB (entityId entity)
, maySerial sType defText
, " PRIMARY KEY UNIQUE"
, mayDefault defText
]
maySerial :: SqlType -> Maybe Text -> Text
maySerial SqlInt64 Nothing = " SERIAL "
maySerial sType _ = " " <> showSqlType sType
mayDefault :: Maybe Text -> Text
mayDefault def = case def of
Nothing -> ""
Just d -> " DEFAULT " <> d
type SafeToRemove = Bool
data AlterColumn = Type SqlType Text
| IsNull | NotNull | Add' Column | Drop SafeToRemove
| Default Text | NoDefault | Update' Text
| AddReference DBName [DBName] [Text] | DropReference DBName
type AlterColumn' = (DBName, AlterColumn)
data AlterTable = AddUniqueConstraint DBName [DBName]
| DropConstraint DBName
data AlterDB = AddTable Text
| AlterColumn DBName AlterColumn'
| AlterTable DBName AlterTable
getColumns :: (Text -> IO Statement)
-> EntityDef
-> IO [Either Text (Either Column (DBName, [DBName]))]
getColumns getter def = do
let sqlv=T.concat ["SELECT "
,"column_name "
,",is_nullable "
,",udt_name "
,",column_default "
,",numeric_precision "
,",numeric_scale "
,"FROM information_schema.columns "
,"WHERE table_catalog=current_database() "
,"AND table_schema=current_schema() "
,"AND table_name=? "
,"AND column_name <> ?"]
stmt <- getter sqlv
let vals =
[ PersistText $ unDBName $ entityDB def
, PersistText $ unDBName $ fieldDB (entityId def)
]
cs <- with (stmtQuery stmt vals) ($$ helper)
let sqlc = T.concat ["SELECT "
,"c.constraint_name, "
,"c.column_name "
,"FROM information_schema.key_column_usage c, "
,"information_schema.table_constraints k "
,"WHERE c.table_catalog=current_database() "
,"AND c.table_catalog=k.table_catalog "
,"AND c.table_schema=current_schema() "
,"AND c.table_schema=k.table_schema "
,"AND c.table_name=? "
,"AND c.table_name=k.table_name "
,"AND c.column_name <> ? "
,"AND c.constraint_name=k.constraint_name "
,"AND NOT k.constraint_type IN ('PRIMARY KEY', 'FOREIGN KEY') "
,"ORDER BY c.constraint_name, c.column_name"]
stmt' <- getter sqlc
us <- with (stmtQuery stmt' vals) ($$ helperU)
return $ cs ++ us
where
getAll front = do
x <- CL.head
case x of
Nothing -> return $ front []
Just [PersistText con, PersistText col] -> getAll (front . (:) (con, col))
Just [PersistByteString con, PersistByteString col] -> getAll (front . (:) (T.decodeUtf8 con, T.decodeUtf8 col))
Just o -> error $ "unexpected datatype returned for postgres o="++show o
helperU = do
rows <- getAll id
return $ map (Right . Right . (DBName . fst . head &&& map (DBName . snd)))
$ groupBy ((==) `on` fst) rows
helper = do
x <- CL.head
case x of
Nothing -> return []
Just x' -> do
col <- liftIO $ getColumn getter (entityDB def) x'
let col' = case col of
Left e -> Left e
Right c -> Right $ Left c
cols <- helper
return $ col' : cols
safeToRemove :: EntityDef -> DBName -> Bool
safeToRemove def (DBName colName)
= any (elem "SafeToRemove" . fieldAttrs)
$ filter ((== DBName colName) . fieldDB)
$ entityFields def
getAlters :: [EntityDef]
-> EntityDef
-> ([Column], [(DBName, [DBName])])
-> ([Column], [(DBName, [DBName])])
-> ([AlterColumn'], [AlterTable])
getAlters defs def (c1, u1) (c2, u2) =
(getAltersC c1 c2, getAltersU u1 u2)
where
getAltersC [] old = map (\x -> (cName x, Drop $ safeToRemove def $ cName x)) old
getAltersC (new:news) old =
let (alters, old') = findAlters defs (entityDB def) new old
in alters ++ getAltersC news old'
getAltersU :: [(DBName, [DBName])]
-> [(DBName, [DBName])]
-> [AlterTable]
getAltersU [] old = map DropConstraint $ filter (not . isManual) $ map fst old
getAltersU ((name, cols):news) old =
case lookup name old of
Nothing -> AddUniqueConstraint name cols : getAltersU news old
Just ocols ->
let old' = filter (\(x, _) -> x /= name) old
in if sort cols == sort ocols
then getAltersU news old'
else DropConstraint name
: AddUniqueConstraint name cols
: getAltersU news old'
isManual (DBName x) = "__manual_" `T.isPrefixOf` x
getColumn :: (Text -> IO Statement)
-> DBName -> [PersistValue]
-> IO (Either Text Column)
getColumn getter tname [PersistText x, PersistText y, PersistText z, d, npre, nscl] =
case d' of
Left s -> return $ Left s
Right d'' ->
case getType z of
Left s -> return $ Left s
Right t -> do
let cname = DBName x
ref <- getRef cname
return $ Right Column
{ cName = cname
, cNull = y == "YES"
, cSqlType = t
, cDefault = fmap stripSuffixes d''
, cDefaultConstraintName = Nothing
, cMaxLen = Nothing
, cReference = ref
}
where
stripSuffixes t =
loop'
[ "::character varying"
, "::text"
]
where
loop' [] = t
loop' (p:ps) =
case T.stripSuffix p t of
Nothing -> loop' ps
Just t' -> t'
getRef cname = do
let sql = T.concat
[ "SELECT COUNT(*) FROM "
, "information_schema.table_constraints "
, "WHERE table_catalog=current_database() "
, "AND table_schema=current_schema() "
, "AND table_name=? "
, "AND constraint_type='FOREIGN KEY' "
, "AND constraint_name=?"
]
let ref = refName tname cname
stmt <- getter sql
with (stmtQuery stmt
[ PersistText $ unDBName tname
, PersistText $ unDBName ref
]) ($$ do
Just [PersistInt64 i] <- CL.head
return $ if i == 0 then Nothing else Just (DBName "", ref))
d' = case d of
PersistNull -> Right Nothing
PersistText t -> Right $ Just t
_ -> Left $ T.pack $ "Invalid default column: " ++ show d
getType "int4" = Right SqlInt32
getType "int8" = Right SqlInt64
getType "varchar" = Right SqlString
getType "date" = Right SqlDay
getType "bool" = Right SqlBool
getType "timestamptz" = Right SqlDayTime
getType "float4" = Right SqlReal
getType "float8" = Right SqlReal
getType "bytea" = Right SqlBlob
getType "time" = Right SqlTime
getType "numeric" = getNumeric npre nscl
getType a = Right $ SqlOther a
getNumeric (PersistInt64 a) (PersistInt64 b) = Right $ SqlNumeric (fromIntegral a) (fromIntegral b)
getNumeric a b = Left $ T.pack $ "Can not get numeric field precision, got: " ++ show a ++ " and " ++ show b ++ " as precision and scale"
getColumn _ _ x =
return $ Left $ T.pack $ "Invalid result from information_schema: " ++ show x
sqlTypeEq :: SqlType -> SqlType -> Bool
sqlTypeEq x y =
T.toCaseFold (showSqlType x) == T.toCaseFold (showSqlType y)
findAlters :: [EntityDef] -> DBName -> Column -> [Column] -> ([AlterColumn'], [Column])
findAlters defs _tablename col@(Column name isNull sqltype def _defConstraintName _maxLen ref) cols =
case filter (\c -> cName c == name) cols of
[] -> ([(name, Add' col)], cols)
Column _ isNull' sqltype' def' _defConstraintName' _maxLen' ref':_ ->
let refDrop Nothing = []
refDrop (Just (_, cname)) = [(name, DropReference cname)]
refAdd Nothing = []
refAdd (Just (tname, a)) =
case find ((==tname) . entityDB) defs of
Just refdef -> [(tname, AddReference a [name] (dbIdColumnsEsc escape refdef))]
Nothing -> error $ "could not find the entityDef for reftable[" ++ show tname ++ "]"
modRef =
if fmap snd ref == fmap snd ref'
then []
else refDrop ref' ++ refAdd ref
modNull = case (isNull, isNull') of
(True, False) -> [(name, IsNull)]
(False, True) ->
let up = case def of
Nothing -> id
Just s -> (:) (name, Update' s)
in up [(name, NotNull)]
_ -> []
modType
| sqlTypeEq sqltype sqltype' = []
| sqltype == SqlDayTime && sqltype' == SqlOther "timestamp" =
[(name, Type sqltype $ T.concat
[ " USING "
, escape name
, " AT TIME ZONE 'UTC'"
])]
| otherwise = [(name, Type sqltype "")]
modDef =
if def == def'
then []
else case def of
Nothing -> [(name, NoDefault)]
Just s -> [(name, Default s)]
in (modRef ++ modDef ++ modNull ++ modType,
filter (\c -> cName c /= name) cols)
getAddReference :: [EntityDef] -> DBName -> DBName -> DBName -> Maybe (DBName, DBName) -> Maybe AlterDB
getAddReference allDefs table reftable cname ref =
case ref of
Nothing -> Nothing
Just (s, _) -> Just $ AlterColumn table (s, AddReference (refName table cname) [cname] id_)
where
id_ = fromMaybe (error $ "Could not find ID of entity " ++ show reftable)
$ do
entDef <- find ((== reftable) . entityDB) allDefs
return $ dbIdColumnsEsc escape entDef
showColumn :: Column -> Text
showColumn (Column n nu sqlType' def _defConstraintName _maxLen _ref) = T.concat
[ escape n
, " "
, showSqlType sqlType'
, " "
, if nu then "NULL" else "NOT NULL"
, case def of
Nothing -> ""
Just s -> " DEFAULT " <> s
]
showSqlType :: SqlType -> Text
showSqlType SqlString = "VARCHAR"
showSqlType SqlInt32 = "INT4"
showSqlType SqlInt64 = "INT8"
showSqlType SqlReal = "DOUBLE PRECISION"
showSqlType (SqlNumeric s prec) = T.concat [ "NUMERIC(", T.pack (show s), ",", T.pack (show prec), ")" ]
showSqlType SqlDay = "DATE"
showSqlType SqlTime = "TIME"
showSqlType SqlDayTime = "TIMESTAMP WITH TIME ZONE"
showSqlType SqlBlob = "BYTEA"
showSqlType SqlBool = "BOOLEAN"
showSqlType (SqlOther (T.toLower -> "integer")) = "INT4"
showSqlType (SqlOther t) = t
showAlterDb :: AlterDB -> (Bool, Text)
showAlterDb (AddTable s) = (False, s)
showAlterDb (AlterColumn t (c, ac)) =
(isUnsafe ac, showAlter t (c, ac))
where
isUnsafe (Drop safeRemove) = not safeRemove
isUnsafe _ = False
showAlterDb (AlterTable t at) = (False, showAlterTable t at)
showAlterTable :: DBName -> AlterTable -> Text
showAlterTable table (AddUniqueConstraint cname cols) = T.concat
[ "ALTER TABLE "
, escape table
, " ADD CONSTRAINT "
, escape cname
, " UNIQUE("
, T.intercalate "," $ map escape cols
, ")"
]
showAlterTable table (DropConstraint cname) = T.concat
[ "ALTER TABLE "
, escape table
, " DROP CONSTRAINT "
, escape cname
]
showAlter :: DBName -> AlterColumn' -> Text
showAlter table (n, Type t extra) =
T.concat
[ "ALTER TABLE "
, escape table
, " ALTER COLUMN "
, escape n
, " TYPE "
, showSqlType t
, extra
]
showAlter table (n, IsNull) =
T.concat
[ "ALTER TABLE "
, escape table
, " ALTER COLUMN "
, escape n
, " DROP NOT NULL"
]
showAlter table (n, NotNull) =
T.concat
[ "ALTER TABLE "
, escape table
, " ALTER COLUMN "
, escape n
, " SET NOT NULL"
]
showAlter table (_, Add' col) =
T.concat
[ "ALTER TABLE "
, escape table
, " ADD COLUMN "
, showColumn col
]
showAlter table (n, Drop _) =
T.concat
[ "ALTER TABLE "
, escape table
, " DROP COLUMN "
, escape n
]
showAlter table (n, Default s) =
T.concat
[ "ALTER TABLE "
, escape table
, " ALTER COLUMN "
, escape n
, " SET DEFAULT "
, s
]
showAlter table (n, NoDefault) = T.concat
[ "ALTER TABLE "
, escape table
, " ALTER COLUMN "
, escape n
, " DROP DEFAULT"
]
showAlter table (n, Update' s) = T.concat
[ "UPDATE "
, escape table
, " SET "
, escape n
, "="
, s
, " WHERE "
, escape n
, " IS NULL"
]
showAlter table (reftable, AddReference fkeyname t2 id2) = T.concat
[ "ALTER TABLE "
, escape table
, " ADD CONSTRAINT "
, escape fkeyname
, " FOREIGN KEY("
, T.intercalate "," $ map escape t2
, ") REFERENCES "
, escape reftable
, "("
, T.intercalate "," id2
, ")"
]
showAlter table (_, DropReference cname) = T.concat
[ "ALTER TABLE "
, escape table
, " DROP CONSTRAINT "
, escape cname
]
tableName :: forall record.
( PersistEntity record
, PersistEntityBackend record ~ SqlBackend
) => record -> Text
tableName = escape . tableDBName
fieldName :: forall record typ.
( PersistEntity record
, PersistEntityBackend record ~ SqlBackend
) => EntityField record typ -> Text
fieldName = escape . fieldDBName
escape :: DBName -> Text
escape (DBName s) =
T.pack $ '"' : go (T.unpack s) ++ "\""
where
go "" = ""
go ('"':xs) = "\"\"" ++ go xs
go (x:xs) = x : go xs
data PostgresConf = PostgresConf
{ pgConnStr :: ConnectionString
, pgPoolSize :: Int
} deriving (Show, Read, Data, Typeable)
instance FromJSON PostgresConf where
parseJSON v = modifyFailure ("Persistent: error loading PostgreSQL conf: " ++) $
flip (withObject "PostgresConf") v $ \o -> do
database <- o .: "database"
host <- o .: "host"
port <- o .:? "port" .!= 5432
user <- o .: "user"
password <- o .: "password"
pool <- o .: "poolsize"
let ci = PG.ConnectInfo
{ PG.connectHost = host
, PG.connectPort = port
, PG.connectUser = user
, PG.connectPassword = password
, PG.connectDatabase = database
}
cstr = PG.postgreSQLConnectionString ci
return $ PostgresConf cstr pool
instance PersistConfig PostgresConf where
type PersistConfigBackend PostgresConf = SqlPersistT
type PersistConfigPool PostgresConf = ConnectionPool
createPoolConfig (PostgresConf cs size) = runNoLoggingT $ createPostgresqlPool cs size
runPool _ = runSqlPool
loadConfig = parseJSON
applyEnv c0 = do
env <- getEnvironment
return $ addUser env
$ addPass env
$ addDatabase env
$ addPort env
$ addHost env c0
where
addParam param val c =
c { pgConnStr = B8.concat [pgConnStr c, " ", param, "='", pgescape val, "'"] }
pgescape = B8.pack . go
where
go ('\'':rest) = '\\' : '\'' : go rest
go ('\\':rest) = '\\' : '\\' : go rest
go ( x :rest) = x : go rest
go [] = []
maybeAddParam param envvar env =
maybe id (addParam param) $
lookup envvar env
addHost = maybeAddParam "host" "PGHOST"
addPort = maybeAddParam "port" "PGPORT"
addUser = maybeAddParam "user" "PGUSER"
addPass = maybeAddParam "password" "PGPASS"
addDatabase = maybeAddParam "dbname" "PGDATABASE"
refName :: DBName -> DBName -> DBName
refName (DBName table) (DBName column) =
DBName $ T.concat [table, "_", column, "_fkey"]
udToPair :: UniqueDef -> (DBName, [DBName])
udToPair ud = (uniqueDBName ud, map snd $ uniqueFields ud)
mockMigrate :: [EntityDef]
-> (Text -> IO Statement)
-> EntityDef
-> IO (Either [Text] [(Bool, Text)])
mockMigrate allDefs _ entity = fmap (fmap $ map showAlterDb) $ do
case partitionEithers [] of
([], old'') -> return $ Right $ migrationText False old''
(errs, _) -> return $ Left errs
where
name = entityDB entity
migrationText exists old'' =
if not exists
then createText newcols fdefs udspair
else let (acs, ats) = getAlters allDefs entity (newcols, udspair) old'
acs' = map (AlterColumn name) acs
ats' = map (AlterTable name) ats
in acs' ++ ats'
where
old' = partitionEithers old''
(newcols', udefs, fdefs) = mkColumns allDefs entity
newcols = filter (not . safeToRemove entity . cName) newcols'
udspair = map udToPair udefs
createText newcols fdefs udspair =
(addTable newcols entity) : uniques ++ references ++ foreignsAlt
where
uniques = flip concatMap udspair $ \(uname, ucols) ->
[AlterTable name $ AddUniqueConstraint uname ucols]
references = mapMaybe (\c@Column { cName=cname, cReference=Just (refTblName, _) } ->
getAddReference allDefs name refTblName cname (cReference c))
$ filter (isJust . cReference) newcols
foreignsAlt = flip map fdefs (\fdef ->
let (childfields, parentfields) = unzip (map (\((_,b),(_,d)) -> (b,d)) (foreignFields fdef))
in AlterColumn name (foreignRefTableDBName fdef, AddReference (foreignConstraintNameDBName fdef) childfields (map escape parentfields)))
mockMigration :: Migration -> IO ()
mockMigration mig = do
smap <- newIORef $ Map.empty
let sqlbackend = SqlBackend { connPrepare = \_ -> do
return Statement
{ stmtFinalize = return ()
, stmtReset = return ()
, stmtExecute = undefined
, stmtQuery = \_ -> return $ return ()
},
connInsertManySql = Nothing,
connInsertSql = undefined,
connStmtMap = smap,
connClose = undefined,
connMigrateSql = mockMigrate,
connBegin = undefined,
connCommit = undefined,
connRollback = undefined,
connEscapeName = escape,
connNoLimit = undefined,
connRDBMS = undefined,
connLimitOffset = undefined,
connLogFunc = undefined}
result = runReaderT $ runWriterT $ runWriterT mig
resp <- result sqlbackend
mapM_ T.putStrLn $ map snd $ snd resp