-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Read and write appropriately from both master and replicated postgresql instances.
--   
--   Please see the README on GitHub at
--   <a>https://github.com/iand675/multipool#readme</a>
@package multipool-persistent-postgresql
@version 0.1.0.1

module Data.MultiPool.Persist.Postgresql
initMultiPool :: (MonadLogger m, MonadUnliftIO m) => ConnectionString -> Int -> [(InstanceName SqlReadBackend, ConnectionString, Int)] -> m (MultiPool SqlBackend)
initMultiPool' :: (MonadLogger m, MonadUnliftIO m) => (MultiPool SqlBackend -> IO (Maybe (InstanceName SqlReadBackend))) -> ConnectionString -> Int -> [(InstanceName SqlReadBackend, ConnectionString, Int)] -> m (MultiPool SqlBackend)

-- | Performs a read on the first replica found that sufficiently
--   up-to-date with the given LSN. This function can be combined with
--   <a>gatherLSNs</a> and some sort of caching mechanism to provide a
--   simple way to scale out reads. An great article on this concept can be
--   found <a>here</a>
--   
--   If no replica is up-to-date with the given LSN, the master instance
--   will be used to run the query.
runReadCurrent :: MonadUnliftIO m => MultiPool SqlBackend -> HashMap (InstanceName SqlReadBackend) LSN -> LSN -> ReaderT SqlReadBackend m a -> m a
getLastLSN :: MonadIO m => ReaderT SqlReadBackend m LSN
gatherLSNs :: MonadUnliftIO m => MultiPool SqlBackend -> m (HashMap (InstanceName SqlReadBackend) LSN)