public static Task <string> GetJsonData(string streamId, int streamVersion)
{
using (var connection = new SqliteConnection(_settings.GetConnectionString(true)))
using (var command = connection.CreateCommand())
{
connection.Open();
command.CommandText = @"SELECT messages.json_data
FROM messages
WHERE messages.stream_id_internal =
(
SELECT streams.id_internal
FROM streams
WHERE streams.id = @streamId)
AND messages.stream_version = @streamVersion";
command.Parameters.Clear();
command.Parameters.AddWithValue("@streamId", streamId);
command.Parameters.AddWithValue("@streamVersion", streamVersion);
using (var reader = command.ExecuteReader(CommandBehavior.SequentialAccess | CommandBehavior.SingleRow))
{
return(Task.FromResult(reader.Read()
? reader.GetTextReader(0).ReadToEnd()
: default(string)));
}
}
}
internal SqliteConnection OpenConnection(bool isReadOnly = true)
{
var connection = new SqliteConnection(_settings.GetConnectionString(isReadOnly));
connection.Open();
using (var command = connection.CreateCommand())
{
command.CommandText = @"PRAGMA foreign_keys = true;
PRAGMA journal_mode = WAL;";
command.ExecuteNonQuery();
}
// register functions.
connection.CreateFunction("split", (string source) => source.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries));
connection.CreateFunction("contains",
(string allIdsBeingSought, string idToSeek) =>
{
var ids = allIdsBeingSought.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
return(ids.Contains(idToSeek, StringComparer.OrdinalIgnoreCase));
});
return(connection);
}