fix: Take PG version into account in --dump-schema

The PG version is only read by the Connection Worker, which is not used in the case dump-schema. Now, the pg version is read in the schema cache queries directly, avoiding this problem in all cases.

Signed-off-by: Wolfgang Walther <walther@technowledgy.de>

src/PostgREST/CLI.hs

@@ -53,7 +53,6 @@ main installSignalHandlers runAppWithSocket CLI{cliCommand, cliPath} = do
 dumpSchema :: AppState -> IO LBS.ByteString
 dumpSchema appState = do
   AppConfig{..} <- AppState.getConfig appState
-  actualPgVersion <- AppState.getPgVersion appState
   result <-
     let transaction = if configDbPreparedStatements then SQL.transaction else SQL.unpreparedTransaction in
     SQL.use (AppState.getPool appState) $
@@ -61,7 +60,6 @@ dumpSchema appState = do
         queryDbStructure
           (toList configDbSchemas)
           configDbExtraSearchPath
-          actualPgVersion
           configDbPreparedStatements
   SQL.release $ AppState.getPool appState
   case result of

src/PostgREST/Config/Database.hs

@@ -1,7 +1,8 @@
 {-# LANGUAGE QuasiQuotes #-}
 
 module PostgREST.Config.Database
-  ( queryDbSettings
+  ( pgVersionStatement
+  , queryDbSettings
   , queryPgVersion
   ) where
 
@@ -20,7 +21,10 @@ import Text.InterpolatedString.Perl6 (q)
 import Protolude
 
 queryPgVersion :: Session PgVersion
-queryPgVersion = statement mempty $ SQL.Statement sql HE.noParams versionRow False
+queryPgVersion = statement mempty pgVersionStatement
+
+pgVersionStatement :: SQL.Statement () PgVersion
+pgVersionStatement = SQL.Statement sql HE.noParams versionRow False
   where
     sql = "SELECT current_setting('server_version_num')::integer, current_setting('server_version')"
     versionRow = HD.singleRow $ PgVersion <$> column HD.int4 <*> column HD.text

src/PostgREST/DbStructure.hs

@@ -41,6 +41,7 @@ import Data.Set                      as S (fromList)
 import Data.Text                     (split)
 import Text.InterpolatedString.Perl6 (q)
 
+import PostgREST.Config.Database          (pgVersionStatement)
 import PostgREST.Config.PgVersion         (PgVersion, pgVersion100)
 import PostgREST.DbStructure.Identifiers  (QualifiedIdentifier (..),
                                            Schema, TableName)
@@ -83,9 +84,10 @@ type ViewColumn = Column
 -- | A SQL query that can be executed independently
 type SqlQuery = ByteString
 
-queryDbStructure :: [Schema] -> [Schema] -> PgVersion -> Bool -> SQL.Transaction DbStructure
-queryDbStructure schemas extraSearchPath pgVer prepared = do
+queryDbStructure :: [Schema] -> [Schema] -> Bool -> SQL.Transaction DbStructure
+queryDbStructure schemas extraSearchPath prepared = do
   SQL.sql "set local schema ''" -- This voids the search path. The following queries need this for getting the fully qualified name(schema.name) of every db object
+  pgVer   <- SQL.statement mempty pgVersionStatement
   tabs    <- SQL.statement mempty $ allTables pgVer prepared
   cols    <- SQL.statement schemas $ allColumns tabs prepared
   srcCols <- SQL.statement (schemas, extraSearchPath) $ pfkSourceColumns cols prepared

src/PostgREST/Workers.hs

@@ -153,11 +153,10 @@ connectionStatus appState =
 loadSchemaCache :: AppState -> IO SCacheStatus
 loadSchemaCache appState = do
   AppConfig{..} <- AppState.getConfig appState
-  actualPgVersion <- AppState.getPgVersion appState
   result <-
     let transaction = if configDbPreparedStatements then SQL.transaction else SQL.unpreparedTransaction in
     SQL.use (AppState.getPool appState) . transaction SQL.ReadCommitted SQL.Read $
-      queryDbStructure (toList configDbSchemas) configDbExtraSearchPath actualPgVersion configDbPreparedStatements
+      queryDbStructure (toList configDbSchemas) configDbExtraSearchPath configDbPreparedStatements
   case result of
     Left e -> do
       let