graphql-engine/server/src-lib/Hasura/Server/Utils.hs
Rakesh Emmadi 0e9d6994ac refactor nested insert mutation and fix returning (fix #844) (#852)
* improved nested insert execution logic

* integrate error path, improve executing 'withExp' and improve tests

* add more readable types in '/Resolve/Insert.hs'

* set conflict context just before executing WITH expression
2018-11-02 19:31:01 +05:30

118 lines
4.0 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Hasura.Server.Utils where
import qualified Database.PG.Query.Connection as Q
import Data.Aeson
import Data.List (group, sort)
import Data.List.Split
import Network.URI
import System.Exit
import System.Process
import qualified Data.ByteString as B
import qualified Data.Text as T
import qualified Data.Text.Encoding as TE
import qualified Data.Text.Encoding.Error as TE
import qualified Data.Text.IO as TI
import qualified Language.Haskell.TH.Syntax as TH
import qualified Text.Ginger as TG
import Hasura.Prelude
jsonHeader :: (T.Text, T.Text)
jsonHeader = ("Content-Type", "application/json; charset=utf-8")
userRoleHeader :: T.Text
userRoleHeader = "x-hasura-role"
accessKeyHeader :: T.Text
accessKeyHeader = "x-hasura-access-key"
userIdHeader :: T.Text
userIdHeader = "x-hasura-user-id"
bsToTxt :: B.ByteString -> T.Text
bsToTxt = TE.decodeUtf8With TE.lenientDecode
-- Parsing postgres database url
-- from: https://github.com/futurice/postgresql-simple-url/
parseDatabaseUrl :: String -> Maybe String -> Maybe Q.ConnInfo
parseDatabaseUrl databaseUrl opts = parseURI databaseUrl >>= uriToConnectInfo opts
uriToConnectInfo :: Maybe String -> URI -> Maybe Q.ConnInfo
uriToConnectInfo opts uri
| uriScheme uri /= "postgres:" && uriScheme uri /= "postgresql:" = Nothing
| otherwise = ($ Q.defaultConnInfo {Q.connOptions = opts}) <$> mkConnectInfo uri
type ConnectInfoChange = Q.ConnInfo -> Q.ConnInfo
mkConnectInfo :: URI -> Maybe ConnectInfoChange
mkConnectInfo uri = case uriPath uri of
('/' : rest) | not (null rest) -> Just $ uriParameters uri
_ -> Nothing
uriParameters :: URI -> ConnectInfoChange
uriParameters uri = (\info -> info { Q.connDatabase = tail $ uriPath uri }) . maybe id uriAuthParameters (uriAuthority uri)
dropLast :: [a] -> [a]
dropLast [] = []
dropLast [_] = []
dropLast (x:xs) = x : dropLast xs
uriAuthParameters :: URIAuth -> ConnectInfoChange
uriAuthParameters uriAuth = port . host . auth
where port = case uriPort uriAuth of
(':' : p) -> \info -> info { Q.connPort = read p }
_ -> id
host = case uriRegName uriAuth of
h -> \info -> info { Q.connHost = unEscapeString h }
auth = case splitOn ":" (uriUserInfo uriAuth) of
[""] -> id
[u] -> \info -> info { Q.connUser = unEscapeString $ dropLast u }
[u, p] -> \info -> info { Q.connUser = unEscapeString u, Q.connPassword = unEscapeString $ dropLast p }
_ -> id
-- Running shell script during compile time
runScript :: FilePath -> TH.Q TH.Exp
runScript fp = do
TH.addDependentFile fp
fileContent <- TH.runIO $ TI.readFile fp
(exitCode, stdOut, stdErr) <- TH.runIO $
readProcessWithExitCode "/bin/sh" [] $ T.unpack fileContent
when (exitCode /= ExitSuccess) $ fail $
"Running shell script " ++ fp ++ " failed with exit code : "
++ show exitCode ++ " and with error : " ++ stdErr
TH.lift stdOut
-- Ginger Templating
type GingerTmplt = TG.Template TG.SourcePos
parseGingerTmplt :: TG.Source -> Either String GingerTmplt
parseGingerTmplt src = either parseE Right res
where
res = runIdentity $ TG.parseGinger' parserOptions src
parserOptions = TG.mkParserOptions resolver
resolver = const $ return Nothing
parseE e = Left $ TG.formatParserError (Just "") e
renderGingerTmplt :: (ToJSON a) => a -> GingerTmplt -> T.Text
renderGingerTmplt v = TG.easyRender (toJSON v)
-- find duplicates
duplicates :: Ord a => [a] -> [a]
duplicates = mapMaybe greaterThanOne . group . sort
where
greaterThanOne l = bool Nothing (Just $ head l) $ length l > 1
_1 :: (a, b, c) -> a
_1 (x, _, _) = x
_2 :: (a, b, c) -> b
_2 (_, y, _) = y
_3 :: (a, b, c) -> c
_3 (_, _, z) = z