Allow multiple schemas to be exposed in one instance (#1450)

The schema to use can be selected through the headers `Accept-Profile` for GET/HEAD and `Content-Profile` for POST/PATCH/PUT/DELETE.

This is based on the https://www.w3.org/TR/dx-prof-conneg/ttps://www.w3.org/TR/dx-prof-conneg/ spec.

Also increase all memory tests by 1M(otherwise CI fails).

Co-authored-by: Mahmoud Kassem <MKassem@gk-software.com>
Co-authored-by: Mahmoud Kassem <mahmoud_k@mail.com>

src/PostgREST/Middleware.hs

@@ -27,7 +27,7 @@ import PostgREST.Config       (AppConfig (..), corsPolicy)
 import PostgREST.Error        (SimpleError (JwtTokenInvalid, JwtTokenMissing),
                                errorResponseFor)
 import PostgREST.QueryBuilder (setLocalQuery, setLocalSearchPathQuery)
-import Protolude
+import Protolude              hiding (head)
 
 runWithClaims :: AppConfig -> JWTAttempt ->
                  (ApiRequest -> H.Transaction Response) ->
@@ -50,7 +50,7 @@ runWithClaims conf eClaims app req =
         appSettingsSql = setLocalQuery mempty <$> configSettings conf
         setRoleSql = maybeToList $ (\x ->
           setLocalQuery mempty ("role", unquoted x)) <$> M.lookup "role" claimsWithRole
-        setSearchPathSql = setLocalSearchPathQuery $ configSchema conf : configExtraSearchPath conf
+        setSearchPathSql = setLocalSearchPathQuery (iSchema req : configExtraSearchPath conf)
         -- role claim defaults to anon if not specified in jwt
         claimsWithRole = M.union claims (M.singleton "role" anon)
         anon = JSON.String . toS $ configAnonRole conf