public void Log <TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func <TState, Exception, string> formatter)
{
if (!IsEnabled(logLevel))
{
return;
}
var stateValues = state as IEnumerable <KeyValuePair <string, object> >;
string formattedMessage = formatter?.Invoke(state, exception);
// If we don't have a message, there's nothing to log.
if (string.IsNullOrEmpty(formattedMessage))
{
return;
}
bool isSystemTrace = Utility.GetStateBoolValue(stateValues, ScriptConstants.LogPropertyIsSystemLogKey);
if (isSystemTrace)
{
// System traces are not logged to files.
return;
}
bool isPrimaryHostTrace = Utility.GetStateBoolValue(stateValues, ScriptConstants.LogPropertyPrimaryHostKey);
if (isPrimaryHostTrace && !_isPrimary())
{
return;
}
if (exception != null)
{
if (exception is FunctionInvocationException ||
exception is AggregateException)
{
// we want to minimize the stack traces for function invocation
// failures, so we drill into the very inner exception, which will
// be the script error
Exception actualException = exception;
while (actualException.InnerException != null)
{
actualException = actualException.InnerException;
}
formattedMessage += $"{Environment.NewLine}{actualException.Message}";
}
else
{
formattedMessage += $"{Environment.NewLine}{exception.ToFormattedString()}";
}
}
formattedMessage = FormatLine(stateValues, logLevel, formattedMessage);
try
{
_fileWriter.AppendLine(formattedMessage);
// flush errors immediately
if (logLevel == LogLevel.Error || exception != null)
{
_fileWriter.Flush();
}
}
catch (Exception)
{
// Make sure the Logger doesn't throw if there are Exceptions (disk full, etc).
}
}
