eventstore-1.2.3: Database/EventStore/Internal.hs
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE ScopedTypeVariables #-}
--------------------------------------------------------------------------------
-- |
-- Module : Database.EventStore
-- Copyright : (C) 2014 Yorick Laupa
-- License : (see the file LICENSE)
--
-- Maintainer : Yorick Laupa <yo.eight@gmail.com>
-- Stability : provisional
-- Portability : non-portable
--
--------------------------------------------------------------------------------
module Database.EventStore.Internal where
--------------------------------------------------------------------------------
import Prelude (String)
import Data.Int
import Data.Maybe
import Data.Time (NominalDiffTime)
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import Data.List.NonEmpty(NonEmpty(..), nonEmpty)
import Network.Connection (TLSSettings)
--------------------------------------------------------------------------------
import Database.EventStore.Internal.Callback
import Database.EventStore.Internal.Command
import Database.EventStore.Internal.Communication
import Database.EventStore.Internal.Connection (connectionBuilder)
import Database.EventStore.Internal.Control hiding (subscribe)
import Database.EventStore.Internal.Discovery
import Database.EventStore.Internal.Exec
import Database.EventStore.Internal.Subscription.Api
import Database.EventStore.Internal.Subscription.Catchup
import Database.EventStore.Internal.Subscription.Message
import Database.EventStore.Internal.Subscription.Persistent
import Database.EventStore.Internal.Subscription.Types
import Database.EventStore.Internal.Subscription.Regular
import Database.EventStore.Internal.Logger
import Database.EventStore.Internal.Manager.Operation.Registry
import Database.EventStore.Internal.Operation (OperationError(..))
import qualified Database.EventStore.Internal.Operations as Op
import Database.EventStore.Internal.Operation.Read.Common
import Database.EventStore.Internal.Operation.Write.Common
import Database.EventStore.Internal.Prelude
import Database.EventStore.Internal.Stream
import Database.EventStore.Internal.Types
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-- Connection
--------------------------------------------------------------------------------
-- | Gathers every connection type handled by the client.
data ConnectionType
= Static String Int
-- ^ HostName and Port.
| Cluster ClusterSettings
| Dns ByteString (Maybe DnsServer) Int
-- ^ Domain name, optional DNS server and port.
--------------------------------------------------------------------------------
-- | Represents a connection to a single EventStore node.
data Connection
= Connection
{ _exec :: Exec
, _settings :: Settings
, _type :: ConnectionType
}
--------------------------------------------------------------------------------
-- | Creates a new 'Connection' to a single node. It maintains a full duplex
-- connection to the EventStore. An EventStore 'Connection' operates quite
-- differently than say a SQL connection. Normally when you use an EventStore
-- connection you want to keep the connection open for a much longer of time
-- than when you use a SQL connection.
--
-- Another difference is that with the EventStore 'Connection' all operations
-- are handled in a full async manner (even if you call the synchronous
-- behaviors). Many threads can use an EvenStore 'Connection' at the same time
-- or a single thread can make many asynchronous requests. To get the most
-- performance out of the connection it is generally recommended to use it in
-- this way.
connect :: Settings -> ConnectionType -> IO Connection
connect settings@Settings{..} tpe = do
disc <- case tpe of
Static host port -> return $ staticEndPointDiscovery host port
Cluster setts -> clusterDnsEndPointDiscovery setts
Dns dom srv port -> return $ simpleDnsEndPointDiscovery dom srv port
logRef <- newLoggerRef s_loggerType s_loggerFilter s_loggerDetailed
mainBus <- newBus logRef settings
builder <- connectionBuilder settings
exec <- newExec settings mainBus builder disc
return $ Connection exec settings tpe
--------------------------------------------------------------------------------
-- | Waits the 'Connection' to be closed.
waitTillClosed :: Connection -> IO ()
waitTillClosed Connection{..} = execWaitTillClosed _exec
--------------------------------------------------------------------------------
-- | Returns a 'Connection' 's 'Settings'.
connectionSettings :: Connection -> Settings
connectionSettings = _settings
--------------------------------------------------------------------------------
-- | Asynchronously closes the 'Connection'.
shutdown :: Connection -> IO ()
shutdown Connection{..} = publishWith _exec SystemShutdown
--------------------------------------------------------------------------------
-- | Sends a single 'Event' to given stream.
sendEvent :: Connection
-> StreamName
-> ExpectedVersion
-> Event
-> Maybe Credentials
-> IO (Async WriteResult)
sendEvent mgr evt_stream exp_ver evt cred =
sendEvents mgr evt_stream exp_ver [evt] cred
--------------------------------------------------------------------------------
-- | Sends a list of 'Event' to given stream.
sendEvents :: Connection
-> StreamName
-> ExpectedVersion
-> [Event]
-> Maybe Credentials
-> IO (Async WriteResult)
sendEvents Connection{..} evt_stream exp_ver evts cred = do
p <- newPromise
let op = Op.writeEvents _settings (streamIdRaw evt_stream) exp_ver cred evts
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Deletes given stream.
deleteStream :: Connection
-> StreamName
-> ExpectedVersion
-> Maybe Bool -- ^ Hard delete
-> Maybe Credentials
-> IO (Async Op.DeleteResult)
deleteStream Connection{..} evt_stream exp_ver hard_del cred = do
p <- newPromise
let op = Op.deleteStream _settings (streamIdRaw evt_stream) exp_ver hard_del cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Represents a multi-request transaction with the EventStore.
data Transaction =
Transaction
{ _tStream :: Text
, _tTransId :: TransactionId
, _tExpVer :: ExpectedVersion
, _tConn :: Connection
}
--------------------------------------------------------------------------------
-- | The id of a 'Transaction'.
newtype TransactionId =
TransactionId { _unTransId :: Int64 }
deriving (Eq, Ord, Show)
--------------------------------------------------------------------------------
-- | Gets the id of a 'Transaction'.
transactionId :: Transaction -> TransactionId
transactionId = _tTransId
--------------------------------------------------------------------------------
-- | Starts a transaction on given stream.
startTransaction :: Connection
-> StreamName -- ^ Stream name
-> ExpectedVersion
-> Maybe Credentials
-> IO (Async Transaction)
startTransaction conn@Connection{..} evt_stream exp_ver cred = do
p <- newPromise
let op = Op.transactionStart _settings (streamIdRaw evt_stream) exp_ver cred
publishWith _exec (SubmitOperation p op)
async $ do
tid <- retrieve p
return Transaction
{ _tStream = streamIdRaw evt_stream
, _tTransId = TransactionId tid
, _tExpVer = exp_ver
, _tConn = conn
}
--------------------------------------------------------------------------------
-- | Asynchronously writes to a transaction in the EventStore.
transactionWrite :: Transaction
-> [Event]
-> Maybe Credentials
-> IO (Async ())
transactionWrite Transaction{..} evts cred = do
p <- newPromise
let Connection{..} = _tConn
raw_id = _unTransId _tTransId
op = Op.transactionWrite _settings _tStream _tExpVer raw_id evts cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Asynchronously commits this transaction.
transactionCommit :: Transaction -> Maybe Credentials -> IO (Async WriteResult)
transactionCommit Transaction{..} cred = do
p <- newPromise
let Connection{..} = _tConn
raw_id = _unTransId _tTransId
op = Op.transactionCommit _settings _tStream _tExpVer raw_id cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | There isn't such of thing in EventStore parlance. Basically, if you want to
-- rollback, you just have to not 'transactionCommit' a 'Transaction'.
transactionRollback :: Transaction -> IO ()
transactionRollback _ = return ()
--------------------------------------------------------------------------------
-- | Reads a single event from given stream.
readEvent :: Connection
-> StreamName
-> EventNumber
-> ResolveLink
-> Maybe Credentials
-> IO (Async (ReadResult EventNumber Op.ReadEvent))
readEvent Connection{..} stream_id evtNum resLinkTos cred = do
p <- newPromise
let evt_num = eventNumberToInt64 evtNum
res_link_tos = resolveLinkToBool resLinkTos
op = Op.readEvent _settings (streamIdRaw stream_id) evt_num res_link_tos cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | When batch-reading a stream, this type-level function maps the result you
-- will have whether you read a regular stream or $all stream. When reading
-- a regular stream, some read-error can occur like the stream got deleted.
-- However read-error cannot occur when reading $all stream (because $all
-- cannot get deleted).
type family BatchResult t where
BatchResult EventNumber = ReadResult EventNumber StreamSlice
BatchResult Position = AllSlice
--------------------------------------------------------------------------------
-- | Reads events from a stream forward.
readEventsForward :: Connection
-> StreamId t
-> t
-> Int32 -- ^ Batch size
-> ResolveLink
-> Maybe Credentials
-> IO (Async (BatchResult t))
readEventsForward conn = readEventsCommon conn Forward
--------------------------------------------------------------------------------
-- | Reads events from a stream backward.
readEventsBackward :: Connection
-> StreamId t
-> t
-> Int32 -- ^ Batch size
-> ResolveLink
-> Maybe Credentials
-> IO (Async (BatchResult t))
readEventsBackward conn = readEventsCommon conn Backward
--------------------------------------------------------------------------------
readEventsCommon :: Connection
-> ReadDirection
-> StreamId t
-> t
-> Int32
-> ResolveLink
-> Maybe Credentials
-> IO (Async (BatchResult t))
readEventsCommon Connection{..} dir streamId start cnt resLinkTos cred = do
p <- newPromise
let res_link_tos = resolveLinkToBool resLinkTos
op =
case streamId of
StreamName{} ->
let name = streamIdRaw streamId
evtNum = eventNumberToInt64 start in
Op.readStreamEvents _settings dir name evtNum cnt res_link_tos cred
All ->
let Position c_pos p_pos = start in
Op.readAllEvents _settings c_pos p_pos cnt res_link_tos dir cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Subscribes to a stream.
subscribe :: Connection
-> StreamId t
-> ResolveLink
-> Maybe Credentials
-> IO (RegularSubscription t)
subscribe Connection{..} stream resLinkTos cred =
newRegularSubscription _exec stream resLnkTos cred
where
resLnkTos = resolveLinkToBool resLinkTos
--------------------------------------------------------------------------------
-- | Subscribes to a stream. If last checkpoint is defined, this will
-- 'readStreamEventsForward' from that event number, otherwise from the
-- beginning. Once last stream event reached up, a subscription request will
-- be sent using 'subscribe'.
subscribeFrom :: Connection
-> StreamId t
-> ResolveLink
-> Maybe t
-> Maybe Int32 -- ^ Batch size
-> Maybe Credentials
-> IO (CatchupSubscription t)
subscribeFrom Connection{..} streamId resLinkTos lastChkPt batch cred =
newCatchupSubscription _exec resLnkTos batch cred streamId $
case streamId of
StreamName{} -> fromMaybe streamStart lastChkPt
All -> fromMaybe positionStart lastChkPt
where
resLnkTos = resolveLinkToBool resLinkTos
--------------------------------------------------------------------------------
subscribeFromCommon :: Connection
-> ResolveLink
-> Maybe Int32
-> Maybe Credentials
-> StreamId t
-> t
-> IO (CatchupSubscription t)
subscribeFromCommon Connection{..} resLinkTos batch cred kind seed =
newCatchupSubscription _exec resLnkTos batch cred kind seed
where
resLnkTos = resolveLinkToBool resLinkTos
--------------------------------------------------------------------------------
-- | Asynchronously sets the metadata for a stream.
setStreamMetadata :: Connection
-> StreamName
-> ExpectedVersion
-> StreamMetadata
-> Maybe Credentials
-> IO (Async WriteResult)
setStreamMetadata Connection{..} evt_stream exp_ver metadata cred = do
p <- newPromise
let name = streamIdRaw evt_stream
op = Op.setMetaStream _settings name exp_ver cred metadata
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Asynchronously gets the metadata of a stream.
getStreamMetadata :: Connection
-> StreamName
-> Maybe Credentials
-> IO (Async StreamMetadataResult)
getStreamMetadata Connection{..} evt_stream cred = do
p <- newPromise
let op = Op.readMetaStream _settings (streamIdRaw evt_stream) cred
publishWith _exec (SubmitOperation p op)
async (retrieve p)
--------------------------------------------------------------------------------
-- | Asynchronously create a persistent subscription group on a stream.
createPersistentSubscription :: Connection
-> Text
-> StreamName
-> PersistentSubscriptionSettings
-> Maybe Credentials
-> IO (Async (Maybe PersistActionException))
createPersistentSubscription Connection{..} grp stream sett cred = do
p <- newPromise
let op = Op.createPersist grp (streamIdRaw stream) sett cred
publishWith _exec (SubmitOperation p op)
async (persistAsync p)
--------------------------------------------------------------------------------
-- | Asynchronously update a persistent subscription group on a stream.
updatePersistentSubscription :: Connection
-> Text
-> StreamName
-> PersistentSubscriptionSettings
-> Maybe Credentials
-> IO (Async (Maybe PersistActionException))
updatePersistentSubscription Connection{..} grp stream sett cred = do
p <- newPromise
let op = Op.updatePersist grp (streamIdRaw stream) sett cred
publishWith _exec (SubmitOperation p op)
async (persistAsync p)
--------------------------------------------------------------------------------
-- | Asynchronously delete a persistent subscription group on a stream.
deletePersistentSubscription :: Connection
-> Text
-> StreamName
-> Maybe Credentials
-> IO (Async (Maybe PersistActionException))
deletePersistentSubscription Connection{..} grp stream cred = do
p <- newPromise
let op = Op.deletePersist grp (streamIdRaw stream) cred
publishWith _exec (SubmitOperation p op)
async (persistAsync p)
--------------------------------------------------------------------------------
-- | Asynchronously connect to a persistent subscription given a group on a
-- stream.
connectToPersistentSubscription :: Connection
-> Text
-> StreamName
-> Int32
-> Maybe Credentials
-> IO PersistentSubscription
connectToPersistentSubscription Connection{..} group stream bufSize cred =
newPersistentSubscription _exec group stream bufSize cred
--------------------------------------------------------------------------------
persistAsync :: Callback (Maybe PersistActionException)
-> IO (Maybe PersistActionException)
persistAsync = either throw return <=< tryRetrieve