Logging¶

Using a Custom Logging Configuration¶

A custom logging configuration file can be provided with the --log-cfg option:

topwrap --log-cfg logger.cfg build --design {design_name.yaml}

Example configuration:

[loggers]
keys=root,frontend,backend

[handlers]
keys=rootStreamHandler,rootFileHandler,frontendStreamHandler,frontendFileHandler,backendStreamHandler,backendFileHandler

[formatters]
keys=rootFormatter,frontendFormatter,backendFormatter

[logger_root]
level=DEBUG
handlers=rootStreamHandler,rootFileHandler

[logger_frontend]
level=DEBUG
handlers=frontendFileHandler,frontendStreamHandler
qualname=topwrap.frontend.yaml.frontend
propagate=0

[logger_backend]
level=DEBUG
handlers=backendFileHandler,backendStreamHandler
qualname=topwrap.backend.sv.backend
propagate=0

[handler_rootStreamHandler]
class=StreamHandler
formatter=rootFormatter
args=(sys.stdout,)

[handler_rootFileHandler]
class=FileHandler
formatter=rootFormatter
args=("topwrap.log",)

[handler_frontendStreamHandler]
class=StreamHandler
formatter=frontendFormatter
args=(sys.stdout,)

[handler_frontendFileHandler]
class=FileHandler
formatter=frontendFormatter
args=("topwrap.log","w")

[handler_backendStreamHandler]
class=StreamHandler
formatter=backendFormatter
args=(sys.stdout,)

[handler_backendFileHandler]
class=FileHandler
formatter=backendFormatter
args=("topwrap.log","w")

[formatter_rootFormatter]
format=%(levelname)s:%(message)s

[formatter_frontendFormatter]
format=%(levelname)s:frontend:%(message)s

[formatter_backendFormatter]
format=%(levelname)s:backend:%(message)s

If both --log-level and --log-cfg are provided, the logging configuration file is loaded first, and the log level specified by --log-level overrides the configured levels.

Creating a New Logger¶

Since Topwrap relies on Python’s standard logging module, users can easily add custom loggers.

Each logger should correspond to a Python module and use the module name as its qualname.

The module name can be obtained by:

printing __name__ inside the module, or
converting the file path into dotted module notation.

For example:

topwrap/frontend/frontend.py

corresponds to:

topwrap.frontend.frontend

Last update: 2026-05-28