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


-- | PostgreSQL logical streaming replication library
--   
--   Please see the README on GitHub at
--   <a>https://github.com/agentultra/postgresql-replicant#readme</a>
@package postgresql-replicant
@version 0.2.0.1

module Database.PostgreSQL.Replicant.Exception
newtype ReplicantException
ReplicantException :: String -> ReplicantException
instance GHC.Show.Show Database.PostgreSQL.Replicant.Exception.ReplicantException
instance GHC.Exception.Type.Exception Database.PostgreSQL.Replicant.Exception.ReplicantException

module Database.PostgreSQL.Replicant.PostgresUtils
postgresEpoch :: IO Int64
mkUTCTime :: (Integer, Int, Int) -> (Int, Int, Pico) -> UTCTime

module Database.PostgreSQL.Replicant.Serialize

-- | Consume the rest of the <tt>Get a</tt> input as a ByteString
consumeByteStringToEnd :: Get ByteString

module Database.PostgreSQL.Replicant.Settings
data PgSettings
PgSettings :: String -> Maybe String -> String -> String -> String -> String -> String -> PgSettings
[pgUser] :: PgSettings -> String
[pgPassword] :: PgSettings -> Maybe String
[pgDbName] :: PgSettings -> String
[pgHost] :: PgSettings -> String
[pgPort] :: PgSettings -> String
[pgSlotName] :: PgSettings -> String

-- | Controls how frequently the primaryKeepAlive thread updates
--   PostgresSQL in <tt>ms</tt>
[pgUpdateDelay] :: PgSettings -> String
pgConnectionString :: PgSettings -> ByteString
instance GHC.Show.Show Database.PostgreSQL.Replicant.Settings.PgSettings
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Settings.PgSettings


-- | <i>Log Sequence Number</i> or LSN is a pointer to a place inside of a
--   WAL log file. It contains the file name and an offset in bytes encoded
--   in two parts.
--   
--   LSNs can be serialized into 64-bit big-endian numbers in the binary
--   protocol but are also represented textually in query results and other
--   places.
--   
--   This module follows a similar convention to many containers libraries
--   and should probably be imported qualified to avoid name clashes if
--   needed.
--   
--   See: <a>https://www.postgresql.org/docs/10/datatype-pg-lsn.html</a>
module Database.PostgreSQL.Replicant.Types.Lsn
data LSN
LSN :: !Int32 -> !Int32 -> LSN

-- | Filepart
[filepart] :: LSN -> !Int32

-- | Offset
[offset] :: LSN -> !Int32

-- | Convert an LSN to a 64-bit integer
toInt64 :: LSN -> Int64

-- | Convert a 64-bit integer to an LSN
fromInt64 :: Int64 -> LSN
lsnParser :: Parser LSN
fromByteString :: ByteString -> Either String LSN

-- | Note that as of bytestring ~0.10.12.0 we don't have upper-case hex
--   encoders but the patch to add them has been merged and when available
--   we should switch to them
toByteString :: LSN -> ByteString

-- | Add a number of bytes to an LSN
add :: LSN -> Int64 -> LSN

-- | Subtract a number of bytes from an LSN
sub :: LSN -> Int64 -> LSN

-- | Subtract two LSN's to calculate the difference of bytes between them.
subLsn :: LSN -> LSN -> Int64
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Types.Lsn.LSN
instance GHC.Show.Show Database.PostgreSQL.Replicant.Types.Lsn.LSN
instance GHC.Classes.Ord Database.PostgreSQL.Replicant.Types.Lsn.LSN
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Types.Lsn.LSN
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Types.Lsn.LSN
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Types.Lsn.LSN


-- | This module has the types and functions for maintaining the client
--   stream state.
--   
--   After initiating a replication stream the wal_sender process on the
--   server may require clients to periodically send progress updates. The
--   wal_sender process uses those updates to maintain its internal view of
--   the clients' state.
--   
--   This enables the server to report on things like replication lag and
--   enables the client to disconnect and restart the stream where it left
--   off.
module Database.PostgreSQL.Replicant.State
data WalProgress
WalProgress :: LSN -> LSN -> LSN -> WalProgress
[walProgressReceived] :: WalProgress -> LSN
[walProgressFlushed] :: WalProgress -> LSN
[walProgressApplied] :: WalProgress -> LSN
newtype WalProgressState
WalProgressState :: MVar WalProgress -> WalProgressState
updateWalProgress :: WalProgressState -> LSN -> IO ()
instance GHC.Show.Show Database.PostgreSQL.Replicant.State.WalProgress
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.State.WalProgress


-- | This module contains the binary protocols messages used in the
--   streaming replication protocol as well as the messages used in the
--   body of the logical stream messages.
module Database.PostgreSQL.Replicant.Message

-- | Indicates whether the server or the client should respond to the
--   message.
data ResponseExpectation
ShouldRespond :: ResponseExpectation
DoNotRespond :: ResponseExpectation

-- | The Postgres WAL sender thread may periodically send these messages.
--   When the server expects the client to respond it updates its internal
--   state of the client based on the response. Failure to respond results
--   in the dreaded "WAL timeout" error.
--   
--   See StandbyStatusUpdate for the message the client should respond
--   with.
data PrimaryKeepAlive
PrimaryKeepAlive :: !Int64 -> !Int64 -> !ResponseExpectation -> PrimaryKeepAlive
[primaryKeepAliveWalEnd] :: PrimaryKeepAlive -> !Int64
[primaryKeepAliveSendTime] :: PrimaryKeepAlive -> !Int64
[primaryKeepAliveResponseExpectation] :: PrimaryKeepAlive -> !ResponseExpectation

-- | Sent by the client. Can be sent periodically or in response to a
--   PrimaryKeepAlive message from the server. Gives the server information
--   about the client stream state.
data StandbyStatusUpdate
StandbyStatusUpdate :: !LSN -> !LSN -> !LSN -> !Int64 -> !ResponseExpectation -> StandbyStatusUpdate
[standbyStatuUpdateLastWalByteReceived] :: StandbyStatusUpdate -> !LSN
[standbyStatusUpdateLastWalByteFlushed] :: StandbyStatusUpdate -> !LSN
[standbyStatusUpdateLastWalByteApplied] :: StandbyStatusUpdate -> !LSN
[standbyStatusUpdateSendTime] :: StandbyStatusUpdate -> !Int64
[standbyStatusUpdateResponseExpectation] :: StandbyStatusUpdate -> !ResponseExpectation

-- | Carries WAL segments in the streaming protocol.
data XLogData
XLogData :: !LSN -> !LSN -> !Int64 -> !ByteString -> XLogData
[xLogDataWalStart] :: XLogData -> !LSN
[xLogDataWalEnd] :: XLogData -> !LSN
[xLogDataSendTime] :: XLogData -> !Int64
[xLogDataWalData] :: XLogData -> !ByteString

-- | Not used yet but enables streaming in hot-standby mode.
data HotStandbyFeedback
HotStandbyFeedback :: !Int64 -> !Int32 -> !Int32 -> HotStandbyFeedback
[hotStandbyFeedbackClientSendTime] :: HotStandbyFeedback -> !Int64
[hotStandbyFeedbackCurrentXmin] :: HotStandbyFeedback -> !Int32
[hotStandbyFeedbackCurrentEpoch] :: HotStandbyFeedback -> !Int32

-- | This structure wraps the two messages sent by the server so that we
--   get a Serialize instance for both.
data WalCopyData
XLogDataM :: !XLogData -> WalCopyData
KeepAliveM :: !PrimaryKeepAlive -> WalCopyData

-- | Wraps Postgres values. Since this library currently supports only the
--   <tt>wal2json</tt> logical decoder plugin we have the JSON values much
--   like Aeson does.
data WalValue
WalString :: !Text -> WalValue
WalNumber :: !Scientific -> WalValue
WalBool :: !Bool -> WalValue
WalNull :: WalValue

-- | Represents a single table column. We only support the
--   <tt>wal2json</tt> logical decoder plugin and make no attempt to parse
--   anything but JSON-like primitives.
data Column
Column :: !Text -> !Text -> !WalValue -> Column
[columnName] :: Column -> !Text
[columnType] :: Column -> !Text
[columnValue] :: Column -> !WalValue
data ColumnParseError
ColumnLengthMatchError :: ColumnParseError

-- | Some WAL output plugins encode column values in three, equal length,
--   heterogeneous lists.
columns :: [Text] -> [Text] -> [WalValue] -> Either ColumnParseError [Column]
fromColumn :: Column -> (Text, Text, WalValue)
fromColumns :: [Column] -> ([Text], [Text], [WalValue])

-- | Represents a single insert query in the logical replication format.
data Insert
Insert :: !String -> !String -> ![Column] -> Insert
[insertSchema] :: Insert -> !String
[insertTable] :: Insert -> !String
[insertColumns] :: Insert -> ![Column]

-- | Represents a single update query in the logical replication format.
data Update
Update :: !Text -> !Text -> ![Column] -> Update
[updateSchema] :: Update -> !Text
[updateTable] :: Update -> !Text
[updateColumns] :: Update -> ![Column]

-- | Represents a single delete query in the logical replication format
data Delete
Delete :: !Text -> !Text -> ![Column] -> Delete
[deleteSchema] :: Delete -> !Text
[deleteTable] :: Delete -> !Text
[deleteColumns] :: Delete -> ![Column]

-- | Occasionally the server may also send these for informational purposes
--   and can be ignored. May be used internally.
data Message
Message :: !Bool -> !Text -> !Text -> Message
[messageTransactional] :: Message -> !Bool
[messagePrefix] :: Message -> !Text
[messageContent] :: Message -> !Text
data WalLogData
WInsert :: !Insert -> WalLogData
WUpdate :: !Update -> WalLogData
WDelete :: !Delete -> WalLogData
WMessage :: !Message -> WalLogData
data Change
Change :: LSN -> [WalLogData] -> Change

-- | Return this LSN in your callback to update the stream state in
--   replicant
[changeNextLSN] :: Change -> LSN

-- | The list of WAL log changes in this transaction.
[changeDeltas] :: Change -> [WalLogData]
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.ResponseExpectation
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.ResponseExpectation
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.ResponseExpectation
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.PrimaryKeepAlive
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.PrimaryKeepAlive
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.PrimaryKeepAlive
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.StandbyStatusUpdate
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.StandbyStatusUpdate
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.StandbyStatusUpdate
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.XLogData
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.XLogData
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.XLogData
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.HotStandbyFeedback
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.HotStandbyFeedback
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.HotStandbyFeedback
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.WalCopyData
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.WalCopyData
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.WalCopyData
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.WalValue
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.WalValue
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.WalValue
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Column
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Column
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.ColumnParseError
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.ColumnParseError
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Insert
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Insert
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Update
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Update
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Delete
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Delete
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Message
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Message
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.WalLogData
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.WalLogData
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.WalLogData
instance GHC.Show.Show Database.PostgreSQL.Replicant.Message.Change
instance GHC.Generics.Generic Database.PostgreSQL.Replicant.Message.Change
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Message.Change
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.Change
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.Change
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.WalLogData
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.WalLogData
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.Message
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.Message
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.Delete
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.Delete
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.Update
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.Update
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.Insert
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.Insert
instance Data.Aeson.Types.FromJSON.FromJSON Database.PostgreSQL.Replicant.Message.WalValue
instance Data.Aeson.Types.ToJSON.ToJSON Database.PostgreSQL.Replicant.Message.WalValue
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.WalCopyData
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.HotStandbyFeedback
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.XLogData
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.StandbyStatusUpdate
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.PrimaryKeepAlive
instance Data.Serialize.Serialize Database.PostgreSQL.Replicant.Message.ResponseExpectation

module Database.PostgreSQL.Replicant.Util
mkInt64 :: Int -> Int64
maybeThrow :: Exception e => e -> Maybe a -> IO a

module Database.PostgreSQL.Replicant.Connection
data ReplicantConnection

-- | Connect to the PostgreSQL server in replication mode
connect :: PgSettings -> IO ReplicantConnection
getConnection :: ReplicantConnection -> Connection

-- | Unsafe function for wrapping regular libpq Connection. This is unsafe
--   because the Connection needs to be set up to send replication
--   commands. Improperly constructed connections can lead to runtime
--   exceptions.
unsafeCreateConnection :: Connection -> ReplicantConnection
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Connection.ReplicantConnection
instance GHC.Show.Show Database.PostgreSQL.Replicant.Connection.ConnectResult
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Connection.ConnectResult


-- | This module contains the PostgreSQL queries, types, and functions for
--   working with querying, creating, and working with replication slots.
module Database.PostgreSQL.Replicant.ReplicationSlot
data ReplicationSlotInfo
ReplicationSlotInfo :: ByteString -> ByteString -> ReplicationSlotType -> ReplicationSlotActive -> LSN -> ReplicationSlotInfo
[slotName] :: ReplicationSlotInfo -> ByteString
[slotPlugin] :: ReplicationSlotInfo -> ByteString
[slotType] :: ReplicationSlotInfo -> ReplicationSlotType
[slotActive] :: ReplicationSlotInfo -> ReplicationSlotActive
[slotRestart] :: ReplicationSlotInfo -> LSN
data ReplicationSlotType
Logical :: ReplicationSlotType
Physical :: ReplicationSlotType
UnknownSlotType :: ReplicationSlotType
parseSlotType :: ByteString -> ReplicationSlotType
data ReplicationSlotActive
Active :: ReplicationSlotActive
Inactive :: ReplicationSlotActive
parseSlotActive :: ByteString -> ReplicationSlotActive
createReplicationSlotCommand :: ReplicantConnection -> ByteString -> IO ByteString

-- | Create a replication slot using synchronous query execution.
--   
--   May throw an exception if the command fails.
createReplicationSlotSync :: ReplicantConnection -> ByteString -> IO ReplicationSlotInfo
getReplicationSlotInfoCommand :: ReplicantConnection -> ByteString -> IO ByteString

-- | Get information about an existing replication slot. Returns
--   <tt>Nothing</tt> when the requested slot cannot be found.
--   
--   May throw an exception if the command query fails.
getReplicationSlotSync :: ReplicantConnection -> ByteString -> IO (Maybe ReplicationSlotInfo)

-- | Create replication slot or retrieve an existing slot.
--   
--   Can throw exceptions from <tt>getReplicationSlotSync</tt> or
--   <tt>createReplicationSlotSync</tt>.
setupReplicationSlot :: ReplicantConnection -> ByteString -> IO ReplicationSlotInfo
instance GHC.Show.Show Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotType
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotType
instance GHC.Show.Show Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotActive
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotActive
instance GHC.Show.Show Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotInfo
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.ReplicationSlot.ReplicationSlotInfo


-- | This module implements the Postgres streaming replication protocol.
--   
--   See:
--   <a>https://www.postgresql.org/docs/9.5/protocol-replication.html</a>
module Database.PostgreSQL.Replicant.Protocol

-- | The information returned by the <tt>IDENTIFY_SYSTEM</tt> command
--   establishes the stream's log start, position, and information about
--   the database.
data IdentifySystem
IdentifySystem :: ByteString -> ByteString -> LSN -> Maybe ByteString -> IdentifySystem
[identifySystemSytemId] :: IdentifySystem -> ByteString
[identifySystemTimeline] :: IdentifySystem -> ByteString
[identifySystemLogPos] :: IdentifySystem -> LSN
[identifySystemDbName] :: IdentifySystem -> Maybe ByteString
identifySystemCommand :: ByteString

-- | Synchronously execute the <tt>IDENTIFY SYSTEM</tt> command which
--   returns some basic system information about the server.
identifySystemSync :: ReplicantConnection -> IO (Maybe IdentifySystem)

-- | Create a <tt>START_REPLICATION_SLOT</tt> query, escaping the slot name
--   passed in by the user.
startReplicationCommand :: ReplicantConnection -> ByteString -> LSN -> IO ByteString

-- | This handles the COPY OUT mode messages. PostgreSQL uses this mode to
--   copy the data from a WAL log file to the socket in the streaming
--   replication protocol.
handleCopyOutData :: TChan PrimaryKeepAlive -> WalProgressState -> ReplicantConnection -> (Change -> IO LSN) -> IO ()
handleReplicationRow :: TChan PrimaryKeepAlive -> WalProgressState -> ReplicantConnection -> ByteString -> (Change -> IO LSN) -> IO ()

-- | Used to re-throw an exception received from the server.
handleReplicationError :: ReplicantConnection -> IO ()
handleReplicationNoop :: IO ()

-- | Initiate the streaming replication protocol handler. This will race
--   the <i>keep-alive</i> and <i>copy data</i> handler threads. It will
--   catch and rethrow exceptions from either thread if any fails or
--   returns.
startReplicationStream :: ReplicantConnection -> ByteString -> LSN -> Int -> (Change -> IO LSN) -> IO ()

-- | This listens on the channel for <i>primary keep-alive messages</i>
--   from the server and responds to them with the <i>update status</i>
--   message using the current WAL stream state. It will attempt to buffer
--   prior update messages when the socket is blocked.
keepAliveHandler :: ReplicantConnection -> TChan PrimaryKeepAlive -> WalProgressState -> IO ()
sendStatusUpdate :: ReplicantConnection -> WalProgressState -> IO ()
instance GHC.Show.Show Database.PostgreSQL.Replicant.Protocol.IdentifySystem
instance GHC.Classes.Eq Database.PostgreSQL.Replicant.Protocol.IdentifySystem


-- | Connect to a PostgreSQL server as a logical replication client and
--   receive changes.
--   
--   The basic API is this:
--   
--   <pre>
--   withLogicalStream defaultSettings $ change -&gt; do
--     print change
--     <a>catch</a> err -&gt; do
--       show err
--   </pre>
--   
--   This is a low-level library meant to give the primitives necessary to
--   library authors to add streaming replication support. The API here to
--   rather simplistic but should be hooked up to something like conduit to
--   provide better ergonomics.
module Database.PostgreSQL.Replicant
data Change
Change :: LSN -> [WalLogData] -> Change

-- | Return this LSN in your callback to update the stream state in
--   replicant
[changeNextLSN] :: Change -> LSN

-- | The list of WAL log changes in this transaction.
[changeDeltas] :: Change -> [WalLogData]

-- | Represents a single table column. We only support the
--   <tt>wal2json</tt> logical decoder plugin and make no attempt to parse
--   anything but JSON-like primitives.
data Column
Column :: !Text -> !Text -> !WalValue -> Column
[columnName] :: Column -> !Text
[columnType] :: Column -> !Text
[columnValue] :: Column -> !WalValue

-- | Represents a single delete query in the logical replication format
data Delete
Delete :: !Text -> !Text -> ![Column] -> Delete
[deleteSchema] :: Delete -> !Text
[deleteTable] :: Delete -> !Text
[deleteColumns] :: Delete -> ![Column]

-- | Represents a single insert query in the logical replication format.
data Insert
Insert :: !String -> !String -> ![Column] -> Insert
[insertSchema] :: Insert -> !String
[insertTable] :: Insert -> !String
[insertColumns] :: Insert -> ![Column]

-- | Occasionally the server may also send these for informational purposes
--   and can be ignored. May be used internally.
data Message
Message :: !Bool -> !Text -> !Text -> Message
[messageTransactional] :: Message -> !Bool
[messagePrefix] :: Message -> !Text
[messageContent] :: Message -> !Text
data PgSettings
PgSettings :: String -> Maybe String -> String -> String -> String -> String -> String -> PgSettings
[pgUser] :: PgSettings -> String
[pgPassword] :: PgSettings -> Maybe String
[pgDbName] :: PgSettings -> String
[pgHost] :: PgSettings -> String
[pgPort] :: PgSettings -> String
[pgSlotName] :: PgSettings -> String

-- | Controls how frequently the primaryKeepAlive thread updates
--   PostgresSQL in <tt>ms</tt>
[pgUpdateDelay] :: PgSettings -> String
data ReplicantConnection

-- | Represents a single update query in the logical replication format.
data Update
Update :: !Text -> !Text -> ![Column] -> Update
[updateSchema] :: Update -> !Text
[updateTable] :: Update -> !Text
[updateColumns] :: Update -> ![Column]
data WalLogData
WInsert :: !Insert -> WalLogData
WUpdate :: !Update -> WalLogData
WDelete :: !Delete -> WalLogData
WMessage :: !Message -> WalLogData

-- | Connect to the PostgreSQL server in replication mode
connect :: PgSettings -> IO ReplicantConnection
getConnection :: ReplicantConnection -> Connection

-- | Unsafe function for wrapping regular libpq Connection. This is unsafe
--   because the Connection needs to be set up to send replication
--   commands. Improperly constructed connections can lead to runtime
--   exceptions.
unsafeCreateConnection :: Connection -> ReplicantConnection

-- | Connect to a PostgreSQL database as a user with the replication
--   attribute and start receiving changes using the logical replication
--   protocol. Logical replication happens at the query level so the
--   changes you get represent the set of queries in a transaction:
--   <i>insert</i>, <i>update</i>, and <i>delete</i>.
--   
--   This function will create the replication slot, if it doesn't exist,
--   or reconnect to it otherwise and restart the stream from where the
--   replication slot left off.
--   
--   This function can throw exceptions in <tt>IO</tt> and shut-down the
--   socket in case of any error.
withLogicalStream :: PgSettings -> (Change -> IO LSN) -> IO ()