/// <summary>
/// Asynchronously adds a log to storage
/// </summary>
/// <param name="channelName">The name of the channel associated with the log</param>
/// <param name="log">The log to add</param>
/// <exception cref="StorageException"/>
public Task PutLog(string channelName, Log log)
{
return(AddTaskToQueue(() =>
{
var logJsonString = LogSerializer.Serialize(log);
var maxSize = _storageAdapter.GetMaxStorageSize();
var logSize = Encoding.UTF8.GetBytes(logJsonString).Length;
if (maxSize < 0)
{
throw new StorageException("Failed to store a log to the database.");
}
if (maxSize <= logSize)
{
throw new StorageException($"Log is too large ({logSize} bytes) to store in database. " +
$"Current maximum database size is {maxSize} bytes.");
}
while (true)
{
try
{
_storageAdapter.Insert(TableName,
new[] { ColumnChannelName, ColumnLogName },
new List <object[]> {
new object[] { channelName, logJsonString }
});
return;
}
catch (StorageFullException)
{
var oldestLog = _storageAdapter.Select(TableName, ColumnChannelName, channelName, string.Empty, null, 1, new string[] { ColumnIdName });
if (oldestLog != null && oldestLog.Count > 0 && oldestLog[0].Length > 0)
{
_storageAdapter.Delete(TableName, ColumnIdName, oldestLog[0][0]);
}
else
{
throw new StorageException("Failed to add a new log. Storage is full and old logs cannot be purged.");
}
}
}
}));
}