Logging

Application logging setup (app.log).

Constructor

Signature

def Logging(
    app: Any
)

Parameters

Name	Type	Description
app	Any	The application instance containing configuration settings for logging.

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Signature

def Logging(
    app: [Celery](../base/celery.md?sid=celery_app_base_celery)
)

Parameters

Name	Type	Description
app	[Celery](../base/celery.md?sid=celery_app_base_celery)	The Celery application instance providing configuration for log formats and color settings

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Methods

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setup()

@classmethod
def setup(
    loglevel: str|int = None,
    logfile: str|file = None,
    redirect_stdouts: bool = False,
    redirect_level: str = 'WARNING',
    colorize: bool = None,
    hostname: str = None
) - > list

Configures the global logging subsystem, handles stdout redirection, and updates environment variables for child processes.

Parameters

Name	Type	Description
loglevel	`str	int` = None
logfile	`str	file` = None
redirect_stdouts	bool = False	Whether to capture and redirect standard output and error to the logger
redirect_level	str = 'WARNING'	The log level used for messages captured from redirected standard streams
colorize	bool = None	Explicit override to enable or disable ANSI color codes in logs
hostname	str = None	The worker hostname used to format the log file name

Returns

Type	Description
list	A list of signal receivers that handled the logging setup, or None if already configured

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redirect_stdouts()

@classmethod
def redirect_stdouts(
    loglevel: str|int = None,
    name: string = 'celery.redirected'
)

Redirects standard output streams to a specific logger and updates environment flags.

Parameters

Name	Type	Description
loglevel	`str	int` = None
name	string = 'celery.redirected'	The name of the logger that will receive the redirected stream data

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setup_logging_subsystem()

@classmethod
def setup_logging_subsystem(
    loglevel: str|int = None,
    logfile: str|file = None,
    format: str = None,
    colorize: bool = None,
    hostname: str = None
) - > list

Performs the low-level configuration of root, multiprocessing, and task loggers while triggering setup signals.

Parameters

Name	Type	Description
loglevel	`str	int` = None
logfile	`str	file` = None
format	str = None	The log message format string
colorize	bool = None	Whether to use colors in the output
hostname	str = None	The hostname used for log file name expansion

Returns

Type	Description
list	The list of signal receivers that responded to the setup_logging signal

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setup_task_loggers()

@classmethod
def setup_task_loggers(
    loglevel: str|int = None,
    logfile: str|file = None,
    format: str = None,
    colorize: bool = None,
    propagate: bool = False
) - > logging.Logger

Setup the task logger. If logfile is not specified, then sys.stderr is used. Will return the base task logger object.

Parameters

Name	Type	Description
loglevel	`str	int` = None
logfile	`str	file` = None
format	str = None	The format string for task log messages
colorize	bool = None	Whether to enable color in task logs
propagate	bool = False	Whether task logs should propagate to the root logger

Returns

Type	Description
logging.Logger	The configured logger instance for celery tasks

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redirect_stdouts_to_logger()

@classmethod
def redirect_stdouts_to_logger(
    logger: logging.Logger,
    loglevel: int|str = None,
    stdout: bool = True,
    stderr: bool = True
) - > [LoggingProxy](../../utils/log/loggingproxy.md?sid=celery_utils_log_loggingproxy)

Redirect :class:sys.stdout and :class:sys.stderr to logger.

Parameters

Name	Type	Description
logger	logging.Logger	Logger instance to redirect to.
loglevel	`int	str` = None
stdout	bool = True	Whether to redirect sys.stdout
stderr	bool = True	Whether to redirect sys.stderr

Returns

Type	Description
[LoggingProxy](../../utils/log/loggingproxy.md?sid=celery_utils_log_loggingproxy)	The proxy object that replaced the standard streams

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supports_color()

@classmethod
def supports_color(
    colorize: bool = None,
    logfile: str|file = None
) - > bool

Determines if the current environment and configuration support ANSI color output.

Parameters

Name	Type	Description
colorize	bool = None	The requested color setting
logfile	`str	file` = None

Returns

Type	Description
bool	True if colors are supported and enabled, False otherwise

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colored()

@classmethod
def colored(
    logfile: str|file = None,
    enabled: bool = None
) - > [colored](../../utils/term/colored.md?sid=celery_utils_term_colored)

Returns a colorizer object based on whether color support is enabled for the given logfile.

Parameters

Name	Type	Description
logfile	`str	file` = None
enabled	bool = None	Explicit override for color enablement

Returns

Type	Description
[colored](../../utils/term/colored.md?sid=celery_utils_term_colored)	An object used to wrap strings in ANSI color codes

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setup_handlers()

@classmethod
def setup_handlers(
    logger: logging.Logger,
    logfile: str|file,
    format: str,
    colorize: bool,
    formatter: logging.Formatter = ColorFormatter
) - > logging.Logger

Attaches a configured log handler to the provided logger if it does not already have one.

Parameters

Name	Type	Description
logger	logging.Logger	The logger to which the handler will be added
logfile	`str	file`
format	str	The format string for the handler's formatter
colorize	bool	Whether the formatter should use color
formatter	logging.Formatter = ColorFormatter	The formatter class to instantiate for the handler

Returns

Type	Description
logging.Logger	The logger instance with the new handler attached

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get_default_logger()

@classmethod
def get_default_logger(
    name: str = 'celery'
) - > logging.Logger

Fetches a logger instance by name, defaulting to the 'celery' namespace.

Parameters

Name	Type	Description
name	str = 'celery'	The name of the logger to retrieve

Returns

Type	Description
logging.Logger	The requested logger instance

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already_setup()

@classmethod
def already_setup() - > bool

Returns whether the logging subsystem has already been initialized in the current process.

Returns

Type	Description
bool	The current setup status flag

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