public SqliteStreamStore(SqliteStreamStoreSettings settings)
: base(settings.MetadataMaxAgeCacheExpire,
settings.MetadataMaxAgeCacheMaxSize,
settings.GetUtcNow,
settings.LogName)
{
_settings = settings;
SqliteCommandExtensions.WithSettings(settings);
_streamStoreNotifier = new Lazy <IStreamStoreNotifier>(() =>
{
if (_settings.CreateStreamStoreNotifier == null)
{
throw new InvalidOperationException(
"Cannot create notifier because supplied createStreamStoreNotifier was null");
}
return(settings.CreateStreamStoreNotifier.Invoke(this));
});
_resolveNextVersion = (messages, direction, currentVersion) =>
{
if (messages.Any())
{
var mVers = messages.Last().StreamVersion;
mVers = direction == ReadDirection.Forward
? mVers + 1
: mVers < StreamVersion.Start ? StreamVersion.Start : mVers - 1;
return(mVers);
}
currentVersion = direction == ReadDirection.Forward
? currentVersion + 1
: currentVersion == StreamVersion.End ? StreamVersion.End : currentVersion - 1;
return(currentVersion);
};
}
public Task <IReadOnlyList <StreamMessage> > Read(
ReadDirection direction,
long?index,
long maxCount,
bool prefectchMessageBody,
CancellationToken cancellationToken = default
)
{
using (var command = CreateCommand())
{
var messages = new List <StreamMessage>();
command.CommandText = @"SELECT streams.id_original As stream_id,
messages.stream_version,
messages.position,
messages.event_id,
messages.created_utc,
messages.type,
messages.json_metadata,
CASE WHEN @includeJsonData = true THEN messages.json_data ELSE null END
FROM messages
INNER JOIN streams
ON messages.stream_id_internal = streams.id_internal
WHERE
CASE WHEN @readForward THEN messages.position >= @position ELSE messages.position <= @position END
ORDER BY
CASE WHEN @readForward THEN messages.position ELSE -messages.position END
LIMIT @count;";
command.Parameters.Clear();
command.Parameters.AddWithValue("@position", index);
command.Parameters.AddWithValue("@count", maxCount);
command.Parameters.AddWithValue("@includeJsonData", prefectchMessageBody);
command.Parameters.AddWithValue("@readForward", direction == ReadDirection.Forward);
var reader = command.ExecuteReader(CommandBehavior.SequentialAccess);
while (reader.Read())
{
var streamId = reader.GetString(0);
var streamVersion = reader.GetInt32(1);
var position = reader.IsDBNull(2) ? Position.End : reader.GetInt64(2);
var messageId = reader.GetGuid(3);
var created = reader.GetDateTime(4);
var type = reader.GetString(5);
var jsonMetadata = reader.GetString(6);
var preloadJson = (!reader.IsDBNull(7) && prefectchMessageBody)
? reader.GetTextReader(7).ReadToEnd()
: default;
var message = new StreamMessage(streamId,
messageId,
streamVersion,
position,
created,
type,
jsonMetadata,
ct => prefectchMessageBody
? Task.FromResult(preloadJson)
: SqliteCommandExtensions.GetJsonData(streamId, streamVersion));
messages.Add(message);
}
return(Task.FromResult <IReadOnlyList <StreamMessage> >(messages));
}
}
