// The odd three-stage initialization improves our chances of correctly tearing down the `LightningEnvironment`s within
// `LogBuffer`s in the event of a failure during start-up. See: https://github.com/CoreyKaylor/Lightning.NET/blob/master/src/LightningDB/LightningEnvironment.cs#L252
public void Load()
{
// At startup, we look for buffers and either delete them if they're empty, or load them
// up if they're not. This garbage collection at start-up is a simplification,
// we might try cleaning up in the background if the gains are worthwhile, although more synchronization
// would be required.
lock (_sync)
{
Directory.CreateDirectory(_bufferPath);
var defaultDataFilePath = Path.Combine(_bufferPath, DataFileName);
if (File.Exists(defaultDataFilePath))
{
_log.Information("Loading the default log buffer in {Path}", _bufferPath);
var buffer = new LogBuffer(_bufferPath, _bufferSizeBytes);
if (buffer.Peek(0).Length == 0)
{
_log.Information("The default buffer is empty and will be removed until more data is received");
buffer.Dispose();
File.Delete(defaultDataFilePath);
var lockFilePath = Path.Combine(_bufferPath, LockFileName);
if (File.Exists(lockFilePath))
{
File.Delete(lockFilePath);
}
}
else
{
_noApiKeyLogBuffer = new ActiveLogBuffer(buffer, _shipperFactory.Create(buffer, _outputConfig.ApiKey));
}
}
foreach (var subfolder in Directory.GetDirectories(_bufferPath))
{
var encodedApiKeyFilePath = Path.Combine(subfolder, ApiKeyFileName);
if (!File.Exists(encodedApiKeyFilePath))
{
_log.Information("Folder {Path} does not appear to be a log buffer; skipping", subfolder);
continue;
}
_log.Information("Loading an API-key specific buffer in {Path}", subfolder);
var apiKey = MachineScopeDataProtection.Unprotect(File.ReadAllText(encodedApiKeyFilePath));
var buffer = new LogBuffer(subfolder, _bufferSizeBytes);
if (buffer.Peek(0).Length == 0)
{
_log.Information("API key-specific buffer in {Path} is empty and will be removed until more data is received", subfolder);
buffer.Dispose();
Directory.Delete(subfolder, true);
}
else
{
var activeBuffer = new ActiveLogBuffer(buffer, _shipperFactory.Create(buffer, apiKey));
_buffersByApiKey.Add(apiKey, activeBuffer);
}
}
}
}
public LogBuffer GetLogBuffer(string apiKey)
{
lock (_sync)
{
if (apiKey == null)
{
if (_noApiKeyLogBuffer == null)
{
_log.Information("Creating a new default log buffer in {Path}", _bufferPath);
var buffer = new LogBuffer(_bufferPath, _bufferSizeBytes);
_noApiKeyLogBuffer = new ActiveLogBuffer(buffer, _shipperFactory.Create(buffer, _outputConfig.ApiKey));
_noApiKeyLogBuffer.Shipper.Start();
}
return(_noApiKeyLogBuffer.Buffer);
}
if (_buffersByApiKey.TryGetValue(apiKey, out var existing))
{
return(existing.Buffer);
}
var subfolder = Path.Combine(_bufferPath, Guid.NewGuid().ToString("n"));
_log.Information("Creating a new API key-specific log buffer in {Path}", subfolder);
Directory.CreateDirectory(subfolder);
File.WriteAllText(Path.Combine(subfolder, ".apikey"), MachineScopeDataProtection.Protect(apiKey));
var newBuffer = new LogBuffer(subfolder, _bufferSizeBytes);
var newActiveBuffer = new ActiveLogBuffer(newBuffer, _shipperFactory.Create(newBuffer, apiKey));
_buffersByApiKey.Add(apiKey, newActiveBuffer);
newActiveBuffer.Shipper.Start();
return(newBuffer);
}
}