From bbb0ce0027b4cdf53a5b1fee831520c0a7565ad3 Mon Sep 17 00:00:00 2001
From: Michael Snoyman <michael@snoyman.com>
Date: Wed, 18 Mar 2015 18:52:57 +0200
Subject: [PATCH] createPostgresqlPoolModified function added

---
 persistent-postgresql/ChangeLog.md            |  5 +--
 .../Database/Persist/Postgresql.hs            | 33 +++++++++++++++----
 .../persistent-postgresql.cabal               |  2 +-
 3 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/persistent-postgresql/ChangeLog.md b/persistent-postgresql/ChangeLog.md
index 40534cd66..4866c8f33 100644
--- a/persistent-postgresql/ChangeLog.md
+++ b/persistent-postgresql/ChangeLog.md
@@ -1,6 +1,7 @@
-## Master
+## 2.1.3
 
-Added a `Show` instance for `PostgresConf`.
+* Added a `Show` instance for `PostgresConf`.
+* `createPostgresqlPoolModified` added, see [relevant mailing list discussion](https://groups.google.com/d/msg/yesodweb/qUXrEN_swEo/O0pFwqwQIdcJ)
 
 ## 2.1.2.1
 
diff --git a/persistent-postgresql/Database/Persist/Postgresql.hs b/persistent-postgresql/Database/Persist/Postgresql.hs
index ace2ffa6a..31be2fe3b 100644
--- a/persistent-postgresql/Database/Persist/Postgresql.hs
+++ b/persistent-postgresql/Database/Persist/Postgresql.hs
@@ -12,6 +12,7 @@ module Database.Persist.Postgresql
     ( withPostgresqlPool
     , withPostgresqlConn
     , createPostgresqlPool
+    , createPostgresqlPoolModified
     , module Database.Persist.Sql
     , ConnectionString
     , PostgresConf (..)
@@ -88,7 +89,7 @@ withPostgresqlPool :: (MonadBaseControl IO m, MonadLogger m, MonadIO m)
                    -- ^ Action to be executed that uses the
                    -- connection pool.
                    -> m a
-withPostgresqlPool ci = withSqlPool $ open' ci
+withPostgresqlPool ci = withSqlPool $ open' (const $ return ()) ci
 
 
 -- | Create a PostgreSQL connection pool.  Note that it's your
@@ -102,17 +103,37 @@ createPostgresqlPool :: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
                      -- ^ Number of connections to be kept open
                      -- in the pool.
                      -> m ConnectionPool
-createPostgresqlPool ci = createSqlPool $ open' ci
-
+createPostgresqlPool = createPostgresqlPoolModified (const $ return ())
+
+-- | Same as 'createPostgresqlPool', but additionally takes a callback function
+-- for some connection-specific tweaking to be performed after connection
+-- creation. This could be used, for example, to change the schema. For more
+-- information, see:
+--
+-- <https://groups.google.com/d/msg/yesodweb/qUXrEN_swEo/O0pFwqwQIdcJ>
+--
+-- Since 2.1.3
+createPostgresqlPoolModified
+    :: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
+    => (PG.Connection -> IO ()) -- ^ action to perform after connection is created
+    -> ConnectionString -- ^ Connection string to the database.
+    -> Int -- ^ Number of connections to be kept open in the pool.
+    -> m ConnectionPool
+createPostgresqlPoolModified modConn ci = createSqlPool $ open' modConn ci
 
 -- | Same as 'withPostgresqlPool', but instead of opening a pool
 -- of connections, only one connection is opened.
 withPostgresqlConn :: (MonadIO m, MonadBaseControl IO m, MonadLogger m)
                    => ConnectionString -> (SqlBackend -> m a) -> m a
-withPostgresqlConn = withSqlConn . open'
+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
 
-open' :: ConnectionString -> LogFunc -> IO SqlBackend
-open' cstr logFunc = PG.connectPostgreSQL cstr >>= openSimpleConn logFunc
 
 -- | Generate a 'Connection' from a 'PG.Connection'
 openSimpleConn :: LogFunc -> PG.Connection -> IO SqlBackend
diff --git a/persistent-postgresql/persistent-postgresql.cabal b/persistent-postgresql/persistent-postgresql.cabal
index bccedf7c0..b6a95d567 100644
--- a/persistent-postgresql/persistent-postgresql.cabal
+++ b/persistent-postgresql/persistent-postgresql.cabal
@@ -1,5 +1,5 @@
 name:            persistent-postgresql
-version:         2.1.2.2
+version:         2.1.3
 license:         MIT
 license-file:    LICENSE
 author:          Felipe Lessa, Michael Snoyman <michael@snoyman.com>