version changed to 3, circle ci to use ghc 7.10.1, stricter import/export in PgQuery and remove of dead code

circle.yml

@@ -3,7 +3,7 @@ machine:
     - createuser --superuser --no-password postgrest_test
     - createdb -O postgrest_test -U ubuntu postgrest_test
   ghc:
-    version: 7.8.3
+    version: 7.10.1
 dependencies:
   override:
     - cabal update

postgrest.cabal

@@ -2,7 +2,7 @@ name:                  postgrest
 description:           Reads the schema of a PostgreSQL database and creates RESTful routes
                        for the tables and views, supporting all HTTP verbs that security
                        permits.
-version:               0.2.11.1
+version:               0.3.0.0
 synopsis:              REST API for any Postgres database
 license:               MIT
 license-file:          LICENSE
@@ -22,6 +22,11 @@ Flag CI
   Default:     False
 
 executable postgrest
+  if flag(ci)
+    ghc-options:       -Wall -W -Werror
+  else
+    ghc-options:       -Wall -W -O2
+
   main-is:             PostgREST/Main.hs
   default-extensions:  OverloadedStrings, ScopedTypeVariables, QuasiQuotes
   default-language:    Haskell2010

src/PostgREST/Auth.hs

@@ -19,7 +19,7 @@ module PostgREST.Auth (
   ) where
 
 --line needed for ghc 7.8
-import           Data.Functor            ((<$>))
+--import           Data.Functor            ((<$>))
 
 import           Data.Aeson              (Value (..), Object)
 import           Data.Aeson.Types        (emptyObject, emptyArray)

src/PostgREST/Main.hs

@@ -13,7 +13,7 @@ import           PostgREST.Types
 
 import           Control.Monad                        (unless)
 import           Control.Monad.IO.Class               (liftIO)
-import           Data.Aeson.Encode.Pretty             (encodePretty)
+import           Data.Aeson                           (encode)
 import           Data.Functor.Identity
 import           Data.Monoid                          ((<>))
 import           Data.String.Conversions              (cs)
@@ -34,7 +34,7 @@ isServerVersionSupported = do
   return $ read (cs row) >= minimumPgVersion
 
 hasqlError :: PgError -> IO a
-hasqlError = error . cs . encodePretty
+hasqlError = error . cs . encode
 
 main :: IO ()
 main = do
@@ -71,11 +71,12 @@ main = do
           <> show minimumPgVersion)
     ) supportedOrError
 
-  roleOrError <- H.session pool $ do
+  -- what was this code for?
-    Identity (role :: Text) <- H.tx Nothing $ H.singleEx
+  -- roleOrError <- H.session pool $ do
-      [H.stmt|SELECT SESSION_USER|]
+  --   Identity (role :: Text) <- H.tx Nothing $ H.singleEx
-    return role
+  --     [H.stmt|SELECT SESSION_USER|]
-  authenticator <- either hasqlError return roleOrError
+  --   return role
+  -- authenticator <- either hasqlError return roleOrError
 
   let txSettings = Just (H.ReadCommitted, Just True)
   metadata <- H.session pool $ H.tx txSettings $ do

src/PostgREST/Middleware.hs

@@ -4,7 +4,7 @@
 module PostgREST.Middleware where
 
 -- needed for ghc 7.8
-import           Data.Functor ((<$>))
+-- import           Data.Functor ((<$>))
 
 import           Data.Maybe                    (fromMaybe, isNothing)
 import           Data.Monoid

src/PostgREST/Parsers.hs

@@ -5,8 +5,8 @@ where
 
 import           Control.Applicative hiding ((<$>))
 --lines needed for ghc 7.8
-import           Data.Functor ((<$>))
+-- import           Data.Functor ((<$>))
-import           Data.Traversable (traverse)
+-- import           Data.Traversable (traverse)
 
 --import           Control.Monad                 (join)
 --import           Data.List                     (delete, find)

src/PostgREST/PgQuery.hs

@@ -3,14 +3,57 @@
 {-# LANGUAGE TypeSynonymInstances #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
-module PostgREST.PgQuery where
+module PostgREST.PgQuery (
+  fromQi
+, insertableValue
+, wrapQuery
+, asJson
+, callProc
+, iffNotT
+, update
+, insertSelect
+, deleteFrom
+, asCsvWithCount
+, asJsonWithCount
+, unquoted
+
+-- format functions
+, pgFmtLit
+, pgFmtIdent
+, pgFmtValue
+, pgFmtCondition
+, pgFmtColumn
+, pgFmtJsonPath
+, pgFmtTable
+, pgFmtField
+, pgFmtSelectItem
+, pgFmtAsJsonPath
+
+-- query transformers (to be removed)
+, withT
+, countT
+, returningStarT
+, whereT
+
+-- query fragments
+, orderF
+, countNoneF
+, countAllF
+, countF
+, locationF
+, asCsvF
+, asJsonSingleF
+, asJsonF
+
+, StatementT
+) where
 
 
 import qualified Hasql                   as H
 import qualified Hasql.Backend           as B
 import qualified Hasql.Postgres          as P
 import           PostgREST.RangeQuery
-import           PostgREST.Types         (OrderTerm (..), QualifiedIdentifier(..))
+import           PostgREST.Types
 
 import           Control.Monad           (join)
 import qualified Data.Aeson              as JSON
@@ -25,7 +68,6 @@ import           Data.Scientific         (FPFormat (..), formatScientific,
 import           Data.String.Conversions (cs)
 import qualified Data.Text               as T
 import           Data.Vector             (empty)
-import qualified Data.Vector             as V
 import qualified Network.HTTP.Types.URI  as Net
 import           Text.Regex.TDFA         ((=~))
 
@@ -37,14 +79,12 @@ instance Monoid PStmt where
     B.Stmt (query <> query') (params <> params') (prep && prep')
   mempty = B.Stmt "" empty True
 type StatementT = PStmt -> PStmt
-
+data JsonbPath =
-
+    ColIdentifier T.Text
-limitT :: Maybe NonnegRange -> StatementT
+  | KeyIdentifier T.Text
-limitT r q =
+  | SingleArrow JsonbPath JsonbPath
-  q <> B.Stmt (" LIMIT " <> limit <> " OFFSET " <> offset <> " ") empty True
+  | DoubleArrow JsonbPath JsonbPath
-  where
+  deriving (Show)
-    limit  = maybe "ALL" (cs . show) $ join $ rangeLimit <$> r
-    offset = cs . show $ fromMaybe 0 $ rangeOffset <$> r
 
 whereT :: QualifiedIdentifier -> Net.Query -> StatementT
 whereT table params q =
@@ -62,24 +102,6 @@ withT (B.Stmt eq ep epre) v (B.Stmt wq wp wpre) =
     (ep <> wp)
     (epre && wpre)
 
-orderT :: [OrderTerm] -> StatementT
-orderT ts q =
-  if L.null ts
-    then q
-    else q <> B.Stmt " order by " empty True <> clause
-  where
-    clause = mconcat $ L.intersperse commaq (map queryTerm ts)
-    queryTerm :: OrderTerm -> PStmt
-    queryTerm t = B.Stmt
-      (" " <> cs (pgFmtIdent $ otTerm t) <> " "
-           <> cs (otDirection t)         <> " "
-           <> maybe "" cs (otNullOrder t) <> " ")
-      empty True
-
-parentheticT :: StatementT
-parentheticT s =
-  s { B.stmtTemplate = " (" <> B.stmtTemplate s <> ") " }
-
 iffNotT :: PStmt -> StatementT
 iffNotT (B.Stmt aq ap apre) (B.Stmt bq bp bpre) =
   B.Stmt
@@ -92,36 +114,9 @@ countT :: StatementT
 countT s =
   s { B.stmtTemplate = "WITH qqq AS (" <> B.stmtTemplate s <> ") SELECT pg_catalog.count(1) FROM qqq" }
 
-countRows :: QualifiedIdentifier  -> PStmt
-countRows t = B.Stmt ("select pg_catalog.count(1) from " <> fromQi t) empty True
-
-countNone :: PStmt
-countNone = B.Stmt "select null" empty True
-
 asCsvWithCount :: QualifiedIdentifier -> StatementT
 asCsvWithCount table = withCount . asCsv table
 
-{--
-WITH source AS (
-	SELECT * FROM projects
-)
-SELECT
-  (
-  	SELECT string_agg(k.kk, ',')
-  	FROM (
-  		SELECT json_object_keys(j)::TEXT as kk
-  		FROM (
-  			SELECT row_to_json(source) as j from source limit 1
-  		) l
-  	) k
-  )
-  || '\r' ||
-  coalesce(string_agg(substring(t::text, 2, length(t::text) - 2), '\r'), '')
-FROM (
-	SELECT * FROM source
-) t;
---}
-
 asCsv :: QualifiedIdentifier -> StatementT
 asCsv table s = s {
   B.stmtTemplate =
@@ -143,34 +138,12 @@ asJson s = s {
 withCount :: StatementT
 withCount s = s { B.stmtTemplate = "pg_catalog.count(t), " <> B.stmtTemplate s }
 
-asJsonRow :: StatementT
-asJsonRow s = s { B.stmtTemplate = "row_to_json(t) from (" <> B.stmtTemplate s <> ") t" }
-
 returningStarT :: StatementT
 returningStarT s = s { B.stmtTemplate = B.stmtTemplate s <> " RETURNING *" }
 
 deleteFrom :: QualifiedIdentifier -> PStmt
 deleteFrom t = B.Stmt ("delete from " <> fromQi t) empty True
 
-insertInto :: QualifiedIdentifier
-              -> V.Vector T.Text
-              -> V.Vector (V.Vector JSON.Value)
-              -> PStmt
-insertInto t cols vals
-  | V.null cols = B.Stmt ("insert into " <> fromQi t <> " default values returning *") empty True
-  | otherwise   = B.Stmt
-    ("insert into " <> fromQi t <> " (" <>
-      T.intercalate ", " (V.toList $ V.map pgFmtIdent cols) <>
-      ") values "
-      <> T.intercalate ", "
-        (V.toList $ V.map (\v -> "("
-            <> T.intercalate ", " (V.toList $ V.map insertableValue v)
-            <> ")"
-          ) vals
-        )
-      <> " returning row_to_json(" <> fromQi t <> ".*)")
-    empty True
-
 insertSelect :: QualifiedIdentifier -> [T.Text] -> [JSON.Value] -> PStmt
 insertSelect t [] _ = B.Stmt
   ("insert into " <> fromQi t <> " default values returning *") empty True
@@ -200,7 +173,7 @@ callProc qi params = do
 wherePred :: QualifiedIdentifier -> Net.QueryItem -> PStmt
 wherePred table (col, predicate) =
   B.Stmt (notOp <> " " <> pgFmtJsonbPath table (cs col) <> " " <> op <> " " <>
-      if opCode `elem` ["is","isnot"] then whiteList value
+      if opCode `elem` ["is","isnot"] then whiteList val
                                  else cs sqlValue)
       empty True
 
@@ -209,60 +182,18 @@ wherePred table (col, predicate) =
     hasNot caseTrue caseFalse = if headPredicate == "not" then caseTrue else caseFalse
     opCode        = hasNot (head rest) headPredicate
     notOp         = hasNot headPredicate ""
-    value         = hasNot (T.intercalate "." $ tail rest) (T.intercalate "." rest)
+    val         = hasNot (T.intercalate "." $ tail rest) (T.intercalate "." rest)
-    sqlValue = pgFmtValue opCode value
+    sqlValue = pgFmtValue opCode val
     op = pgFmtOperator opCode
 
-
 whiteList :: T.Text -> T.Text
 whiteList val = fromMaybe
   (cs (pgFmtLit val) <> "::unknown ")
   (L.find ((==) . T.toLower $ val) ["null","true","false"])
 
-pgFmtValue :: T.Text -> T.Text -> T.Text
-pgFmtValue opCode value =
-  case opCode of
-    "like" -> unknownLiteral $ T.map star value
-    "ilike" -> unknownLiteral $ T.map star value
-    "in" -> "(" <> T.intercalate ", " (map unknownLiteral $ T.split (==',') value) <> ") "
-    "notin" -> "(" <> T.intercalate ", " (map unknownLiteral $ T.split (==',') value) <> ") "
-    "@@" -> "to_tsquery(" <> unknownLiteral value <> ") "
-    _    -> unknownLiteral value
-  where
-    star c = if c == '*' then '%' else c
-    unknownLiteral = (<> "::unknown ") . pgFmtLit
-
-pgFmtOperator :: T.Text -> T.Text
-pgFmtOperator opCode =
-  case opCode of
-    "eq"  -> "="
-    "gt"  -> ">"
-    "lt"  -> "<"
-    "gte" -> ">="
-    "lte" -> "<="
-    "neq" -> "<>"
-    "like"-> "like"
-    "ilike"-> "ilike"
-    "in"  -> "in"
-    "notin" -> "not in"
-    "is"    -> "is"
-    "isnot" -> "is not"
-    "@@" -> "@@"
-    _     -> "="
-
-commaq :: PStmt
-commaq  = B.Stmt ", " empty True
-
 andq :: PStmt
 andq = B.Stmt " and " empty True
 
-data JsonbPath =
-    ColIdentifier T.Text
-  | KeyIdentifier T.Text
-  | SingleArrow JsonbPath JsonbPath
-  | DoubleArrow JsonbPath JsonbPath
-  deriving (Show)
-
 parseJsonbPath :: T.Text -> Maybe JsonbPath
 parseJsonbPath p =
   case T.splitOn "->>" p of
@@ -273,35 +204,6 @@ parseJsonbPath p =
         (KeyIdentifier b)
     _ -> Nothing
 
-pgFmtJsonbPath :: QualifiedIdentifier -> T.Text -> T.Text
-pgFmtJsonbPath table p =
-  pgFmtJsonbPath' $ fromMaybe (ColIdentifier p) (parseJsonbPath p)
-  where
-    pgFmtJsonbPath' (ColIdentifier i) = fromQi table <> "." <> pgFmtIdent i
-    pgFmtJsonbPath' (KeyIdentifier i) = pgFmtLit i
-    pgFmtJsonbPath' (SingleArrow a b) =
-      pgFmtJsonbPath' a <> "->" <> pgFmtJsonbPath' b
-    pgFmtJsonbPath' (DoubleArrow a b) =
-      pgFmtJsonbPath' a <> "->>" <> pgFmtJsonbPath' b
-
-pgFmtIdent :: T.Text -> T.Text
-pgFmtIdent x =
-  let escaped = T.replace "\"" "\"\"" (trimNullChars $ cs x) in
-  if (cs escaped :: BS.ByteString) =~ danger
-    then "\"" <> escaped <> "\""
-    else escaped
-
-  where danger = "^$|^[^a-z_]|[^a-z_0-9]" :: BS.ByteString
-
-pgFmtLit :: T.Text -> T.Text
-pgFmtLit x =
-  let trimmed = trimNullChars x
-      escaped = "'" <> T.replace "'" "''" trimmed <> "'"
-      slashed = T.replace "\\" "\\\\" escaped in
-  if T.isInfixOf "\\\\" escaped
-    then "E" <> slashed
-    else slashed
-
 trimNullChars :: T.Text -> T.Text
 trimNullChars = T.takeWhile (/= '\x0')
 
@@ -325,10 +227,6 @@ insertableValue :: JSON.Value -> T.Text
 insertableValue JSON.Null = "null"
 insertableValue v = insertableText $ unquoted v
 
-paramFilter :: JSON.Value -> T.Text
-paramFilter JSON.Null = "is.null"
-paramFilter v = "eq." <> unquoted v
-
 wrapQuery :: T.Text -> [T.Text] -> Maybe NonnegRange -> T.Text
 wrapQuery source selectColumns range =
   withSourceF source <>
@@ -337,6 +235,8 @@ wrapQuery source selectColumns range =
   " " <>
   fromF ( limitF range )
 
+
+-- query fragments
 withSourceF :: T.Text -> T.Text
 withSourceF s = "WITH source AS (" <> s <>")"
 
@@ -406,3 +306,108 @@ orderF ts =
            <> cs (pgFmtIdent $ otTerm t) <> " "
            <> cs (otDirection t)         <> " "
            <> maybe "" cs (otNullOrder t) <> " "
+
+-- formating functions
+
+pgFmtValue :: T.Text -> T.Text -> T.Text
+pgFmtValue opCode val =
+ case opCode of
+   "like" -> unknownLiteral $ T.map star val
+   "ilike" -> unknownLiteral $ T.map star val
+   "in" -> "(" <> T.intercalate ", " (map unknownLiteral $ T.split (==',') val) <> ") "
+   "notin" -> "(" <> T.intercalate ", " (map unknownLiteral $ T.split (==',') val) <> ") "
+   "@@" -> "to_tsquery(" <> unknownLiteral val <> ") "
+   _    -> unknownLiteral val
+ where
+   star c = if c == '*' then '%' else c
+   unknownLiteral = (<> "::unknown ") . pgFmtLit
+
+pgFmtOperator :: T.Text -> T.Text
+pgFmtOperator opCode =
+ case opCode of
+   "eq"  -> "="
+   "gt"  -> ">"
+   "lt"  -> "<"
+   "gte" -> ">="
+   "lte" -> "<="
+   "neq" -> "<>"
+   "like"-> "like"
+   "ilike"-> "ilike"
+   "in"  -> "in"
+   "notin" -> "not in"
+   "is"    -> "is"
+   "isnot" -> "is not"
+   "@@" -> "@@"
+   _     -> "="
+
+pgFmtJsonbPath :: QualifiedIdentifier -> T.Text -> T.Text
+pgFmtJsonbPath table p =
+ pgFmtJsonbPath' $ fromMaybe (ColIdentifier p) (parseJsonbPath p)
+ where
+   pgFmtJsonbPath' (ColIdentifier i) = fromQi table <> "." <> pgFmtIdent i
+   pgFmtJsonbPath' (KeyIdentifier i) = pgFmtLit i
+   pgFmtJsonbPath' (SingleArrow a b) =
+     pgFmtJsonbPath' a <> "->" <> pgFmtJsonbPath' b
+   pgFmtJsonbPath' (DoubleArrow a b) =
+     pgFmtJsonbPath' a <> "->>" <> pgFmtJsonbPath' b
+
+pgFmtIdent :: T.Text -> T.Text
+pgFmtIdent x =
+ let escaped = T.replace "\"" "\"\"" (trimNullChars $ cs x) in
+ if (cs escaped :: BS.ByteString) =~ danger
+   then "\"" <> escaped <> "\""
+   else escaped
+
+ where danger = "^$|^[^a-z_]|[^a-z_0-9]" :: BS.ByteString
+
+pgFmtLit :: T.Text -> T.Text
+pgFmtLit x =
+ let trimmed = trimNullChars x
+     escaped = "'" <> T.replace "'" "''" trimmed <> "'"
+     slashed = T.replace "\\" "\\\\" escaped in
+ if T.isInfixOf "\\\\" escaped
+   then "E" <> slashed
+   else slashed
+
+pgFmtCondition :: QualifiedIdentifier -> Filter -> T.Text
+pgFmtCondition table (Filter (col,jp) ops val) =
+ notOp <> " " <> sqlCol  <> " " <> pgFmtOperator opCode <> " " <>
+   if opCode `elem` ["is","isnot"] then whiteList (getInner val) else sqlValue
+ where
+   headPredicate:rest = T.split (=='.') ops
+   hasNot caseTrue caseFalse = if headPredicate == "not" then caseTrue else caseFalse
+   opCode      = hasNot (head rest) headPredicate
+   notOp       = hasNot headPredicate ""
+   sqlCol = case val of
+     VText _ -> pgFmtColumn table col <> pgFmtJsonPath jp
+     VForeignKey qi _ -> pgFmtColumn qi col
+   sqlValue = valToStr val
+   getInner v = case v of
+     VText s -> s
+     _      -> ""
+   valToStr v = case v of
+     VText s -> pgFmtValue opCode s
+     VForeignKey (QualifiedIdentifier s _) (ForeignKey ft fc) -> pgFmtColumn (QualifiedIdentifier s ft) fc
+
+pgFmtColumn :: QualifiedIdentifier -> T.Text -> T.Text
+pgFmtColumn table "*" = fromQi table <> ".*"
+pgFmtColumn table c = fromQi table <> "." <> pgFmtIdent c
+
+pgFmtJsonPath :: Maybe JsonPath -> T.Text
+pgFmtJsonPath (Just [x]) = "->>" <> pgFmtLit x
+pgFmtJsonPath (Just (x:xs)) = "->" <> pgFmtLit x <> pgFmtJsonPath ( Just xs )
+pgFmtJsonPath _ = ""
+
+pgFmtTable :: Table -> T.Text
+pgFmtTable Table{tableSchema=s, tableName=n} = fromQi $ QualifiedIdentifier s n
+
+pgFmtField :: QualifiedIdentifier -> Field -> T.Text
+pgFmtField table (c, jp) = pgFmtColumn table c <> pgFmtJsonPath jp
+
+pgFmtSelectItem :: QualifiedIdentifier -> SelectItem -> T.Text
+pgFmtSelectItem table (f@(_, jp), Nothing) = pgFmtField table f <> pgFmtAsJsonPath jp
+pgFmtSelectItem table (f@(_, jp), Just cast ) = "CAST (" <> pgFmtField table f <> " AS " <> cast <> " )" <> pgFmtAsJsonPath jp
+
+pgFmtAsJsonPath :: Maybe JsonPath -> T.Text
+pgFmtAsJsonPath Nothing = ""
+pgFmtAsJsonPath (Just xx) = " AS " <> last xx

src/PostgREST/QueryBuilder.hs

@@ -10,9 +10,9 @@ import           Data.Text         hiding (filter, find, foldr, head, last, map,
                                     null, zipWith)
 import           Control.Applicative
 import           Data.Tree
-import           PostgREST.PgQuery (fromQi,
+import           PostgREST.PgQuery (fromQi, pgFmtCondition, pgFmtSelectItem,
-                                    pgFmtIdent, pgFmtLit, pgFmtOperator,
+                                    pgFmtIdent, pgFmtCondition,
-                                    pgFmtValue, whiteList, insertableValue, orderF)
+                                    insertableValue, orderF)
 import           PostgREST.Types
 --import qualified Data.Vector       as V (empty)
 --import qualified Hasql.Backend     as B
@@ -161,47 +161,3 @@ requestToQuery schema (Node (Insert _ flds vals, (mainTbl, _)) _) =
     --       ) vals
     --     )
     --   <> " returning row_to_json(" <> fromQi t <> ".*)")
-
-
-pgFmtCondition :: QualifiedIdentifier -> Filter -> Text
-pgFmtCondition table (Filter (col,jp) ops val) =
-  notOp <> " " <> sqlCol  <> " " <> pgFmtOperator opCode <> " " <>
-    if opCode `elem` ["is","isnot"] then whiteList (getInner val) else sqlValue
-  where
-    headPredicate:rest = split (=='.') ops
-    hasNot caseTrue caseFalse = if headPredicate == "not" then caseTrue else caseFalse
-    opCode      = hasNot (head rest) headPredicate
-    notOp       = hasNot headPredicate ""
-    sqlCol = case val of
-      VText _ -> pgFmtColumn table col <> pgFmtJsonPath jp
-      VForeignKey qi _ -> pgFmtColumn qi col
-    sqlValue = valToStr val
-    getInner v = case v of
-      VText s -> s
-      _      -> ""
-    valToStr v = case v of
-      VText s -> pgFmtValue opCode s
-      VForeignKey (QualifiedIdentifier s _) (ForeignKey ft fc) -> pgFmtColumn (QualifiedIdentifier s ft) fc
-
-pgFmtColumn :: QualifiedIdentifier -> Text -> Text
-pgFmtColumn table "*" = fromQi table <> ".*"
-pgFmtColumn table c = fromQi table <> "." <> pgFmtIdent c
-
-pgFmtJsonPath :: Maybe JsonPath -> Text
-pgFmtJsonPath (Just [x]) = "->>" <> pgFmtLit x
-pgFmtJsonPath (Just (x:xs)) = "->" <> pgFmtLit x <> pgFmtJsonPath ( Just xs )
-pgFmtJsonPath _ = ""
-
-pgFmtTable :: Table -> Text
-pgFmtTable Table{tableSchema=s, tableName=n} = fromQi $ QualifiedIdentifier s n
-
-pgFmtField :: QualifiedIdentifier -> Field -> Text
-pgFmtField table (c, jp) = pgFmtColumn table c <> pgFmtJsonPath jp
-
-pgFmtSelectItem :: QualifiedIdentifier -> SelectItem -> Text
-pgFmtSelectItem table (f@(_, jp), Nothing) = pgFmtField table f <> asJsonPath jp
-pgFmtSelectItem table (f@(_, jp), Just cast ) = "CAST (" <> pgFmtField table f <> " AS " <> cast <> " )" <> asJsonPath jp
-
-asJsonPath :: Maybe JsonPath -> Text
-asJsonPath Nothing = ""
-asJsonPath (Just xx) = " AS " <> last xx