Logging services

Ready-to-use Logger Implementations

The SDK contains the following implementations of the OnixS::CME::MDH::Logger abstractions:

Logger implementation	Description
OnixS::CME::MDH::FileLogger	Implements logging services over text-based files. Logged data is stored in files which may be limited by size. Once the file reaches its limit, the logger detaches logged data, backs it up and starts a new file.
OnixS::CME::MDH::NullLogger	Logs nothing. The handler suppresses logging if the instance of this class is bound to it.

Note

An OnixS::CME::MDH::Logger successor instance can be bound to multiple OnixS::CME::MDH::Handler instances.

Binding Logger to the handler

The following example demonstrates how to configure and bind a file-based logger to the handler:

struct FileLoggerIssueTracer : public FileLoggerListener
{
    void onFileLoggerIssue(const FileLogger& logger, const Char* issue) override
    {
        std::cout << "ALERT!!! An issue occurred while logging data. " << issue << std::endl;
    }
};

Handler handler;
handler.settings().channel(310).connectivityConfigurationFile("config.xml")
                  .logging().debug().traceMessages(MessageTracing::SbeFormat);

FileLoggerSettings loggerSettings;

loggerSettings.filename(makeLogFilename(handler.settings().channel()));
loggerSettings.severityLevel(LogSeverity::Debug);

FileLoggerIssueTracer loggerTracer;

FileLogger logger(loggerSettings, &loggerTracer);

handler.settings().logging().logger(&logger);