Logging

This page describes the logging strategy and the mechanisms implemented.

Features

Logging occurs at two levels:

• Operating system: services can record a number of events in files located in /var/log or send them to a log manager such as syslog.
• Business application: applications and the platform generate events related to the operation of the product.

Only business events are covered in this documentation.

Architecture

Logging uses the system messaging infrastructure through specific topics system/events.

Debug Level

The debug level is set using the command system/events/set_loglevel.

Emitting an Event

Sharing log information is done via notifications system/events/[loglevel] where loglevel can be:

• debug: Debugging information
• info: General information
• warn: Warning
• error: Software error impacting only part of the system functions
• critical: Software or hardware error preventing the system from operating

Event emission is simplified through the Python class Logger. It is used as follows:

Logger().debug("Debug message", "Module name")
or Logger().info("Informational message").

Recording

The platform automatically saves all events at or above the level defined by the set_loglevel command (or info by default) into a file that can be copied or downloaded on demand. The logging level can be configured to keep only a subset of events.

Retrieving the Log

The command to retrieve the log is system/events/save_log.