Class: QgsLogger

class qgis.core.QgsLogger

Bases: sip.wrapper

QgsLogger is a class to print debug/warning/error messages to the console. The advantage of this class over iostream & co. is that the output can be controlled with environment variables: QGIS_DEBUG is an int describing what debug messages are written to the console. If the debug level of a message is <= QGIS_DEBUG, the message is written to the console. It the variable QGIS_DEBUG is not defined, it defaults to 1 for debug mode and to 0 for release mode QGIS_DEBUG_FILE may contain a file name. Only the messages from this file are printed (provided they have the right debuglevel). If QGIS_DEBUG_FILE is not set, messages from all files are printed

QGIS_LOG_FILE may contain a file name. If set, all messages will be appended to this file rather than to stdout.

Enums

Methods

critical Goes to qCritical
debug Goes to qDebug.
debugLevel Reads the environment variable QGIS_DEBUG and converts it to int.
fatal Goes to qFatal
logFile Reads the environment variable QGIS_LOG_FILE.
logMessageToFile Logs the message passed in to the logfile defined in QGIS_LOG_FILE if any.
warning Goes to qWarning

Signals

Attributes

critical(msg: str)

Goes to qCritical

debug(msg: str, debuglevel: int = 1, file: str = None, function: str = None, line: int = -1)

Goes to qDebug.

Parameters:
  • msg – the message to be printed
  • debuglevel
  • file – file name where the message comes from
  • function – function where the message comes from
  • line – place in file where the message comes from*

debug(var: str, val: int, debuglevel: int = 1, file: str = None, function: str = None, line: int = -1) Similar to the previous method, but prints a variable int-value pair

debugLevel() → int

Reads the environment variable QGIS_DEBUG and converts it to int. If QGIS_DEBUG is not set, the function returns 1 if QGISDEBUG is defined and 0 if not*

fatal(msg: str)

Goes to qFatal

logFile() → str

Reads the environment variable QGIS_LOG_FILE. Returns NULL if the variable is not set, otherwise returns a file name for writing log messages to.*

logMessageToFile(message: str)

Logs the message passed in to the logfile defined in QGIS_LOG_FILE if any. *

warning(msg: str)

Goes to qWarning