The TANGO Logging Service Status Implementation details Possible enhancements

TLS: Status Usable prototype Available for C++ TANGO devices… –…but easily portable Java (log4j + port of the C++ implementation) Python (binding of the DeviceProxy class) –tested under Linux and Win32 Logging is controlled on a per device basis –TANGO Device = smallest controllable entity –Logging Level 1 device 1 logging level (for all targets) OFF < FATAL < ERROR < WARN < INFO < DEBUG –Logging Targets 1. Console (cout) N. XML Files (Chainsaw format) N. LogConsumer device or any device::log(DevVarStringArray)

TLS: Status Controlling the logging behavior of a device startup (static configuration) logging from the device constructor 2 device properties –logging_level –logging_target no command line option (required?) runtime (dynamic configuration) change logging level add/remove logging targets 2 ways –Dserver’s TANGO commands –DeviceProxy methods (requests forwarded to DServer)

TLS: Status Syntax –10 easy to use macros 5 with “printf” like syntax: –LOG_{FATAL, ERROR, WARN, INFO, DEBUG} –LOG_DEBUG((“Msg#%d - Hello world”, i++)); 5 with C++ stream syntax: –{FATAL, ERROR, WARN, INFO, DEBUG}_STREAM –DEBUG_STREAM << “Msg#” << i++ << “- Hello world” << ENDLOG;

TLS: Status Limitations –Can’t log TANGO core messages  Granularity : one logger per device cout1…4 macros should use the “current” device’s logger. How to do this? TSS required –attach device’s logger to the current thread in CORBA methods (IDL) –polling thread uses the DServer’s logger –map cout1…4 to {INFO or DEBUG}_STREAM –map endl to ENDLOG Side effects and drawbacks –example: Dserver::Init No perfect solution! Conclusion?

TLS: Implementation Details TANGO Core: DServer AddLoggingTarget( [{devname_pattern, tg_type, tg_name}, …]) RemoveLoggingTarget( [{devname_pattern, tg_type, tg_name}, …]) GetLoggingLevel ([devname]) SetLoggingLevel ([level], [devname]) GetLoggingTarget (devname) StopLogging () StartLogging () C++ API: DeviceProxy add_logging_target remove_logging_target get_logging_level set_logging_level (devname) get_logging_target (devname)

TLS: Implementation Details Compatibility –Use DeviceImplExt to extend DeviceImpl TLS is a TANGO option –#define TANGO_HAS_LOG4CPP

TLS: Possible Enhacements LogConsumer Targets –Use TANGO events… use case: machine (notification service) simplify “producer” code –only one connection –worse case: only one “zombie appender” per device “logging_channel” device property –Use TANGO Asynchronous Calls use case: experiments (no notification service) send and forget (non blocking mode)

TLS: Possible Enhacements File Targets –rolling mechanism(s) RollingFileAppender and/or DailyRollingFileAppender –logging_path property Console Target –any suggestion?

TLS: Demo