Editing TracLogging

= Trac Logging [[TracGuideToc]] Trac supports logging of system messages using the standard [http://docs.python.org/library/logging.html logging module] that comes with Python. Logging is configured in the `[logging]` section in [wiki:TracIni#logging-section trac.ini]. == Supported Logging Methods The log method is set using the `log_type` option in [wiki:TracIni#logging-section trac.ini], which takes any of the following values: '''none'':: Suppress all log messages. '''file''':: Log messages to a file, specified with the `log_file` option in [wiki:TracIni#logging-section trac.ini]. Relative paths in `log_file` are resolved relative to the `log` directory of the environment. '''stderr''':: Output all log entries to console ([wiki:TracStandalone tracd] only). '''syslog''':: (UNIX) Send all log messages to the local syslogd via named pipe `/dev/log`. By default, syslog will write them to the file /var/log/messages. '''eventlog''':: (Windows) Use the system's NT Event Log for Trac logging. == Log Levels The verbosity level of logged messages can be set using the `log_level` option in [wiki:TracIni#logging-section trac.ini]. The log level defines the minimum level of urgency required for a message to be logged, and those levels are: '''CRITICAL''':: Log only the most critical (typically fatal) errors. '''ERROR''':: Log failures, bugs and errors. '''WARN''':: Log warnings, non-interrupting events. '''INFO''':: Diagnostic information, log information about all processing. '''DEBUG''':: Trace messages, profiling, etc. Additionally, you can enable logging of SQL statements at debug level. This is turned off by default, as it's very verbose. Set `[trac] debug_sql = yes` in TracIni to activate. == Log Format The output format for log entries can be specified through the `log_format` option in [wiki:TracIni#logging-section trac.ini]. The format is a string which can contain any of the [http://docs.python.org/library/logging.html#logrecord-attributes Python logging Formatter variables]. Additonally, the following Trac-specific variables can be used: '''$(basename)s''':: The last path component of the current environment. '''$(path)s''':: The absolute path for the current environment. '''$(project)s''':: The originating project's name. Note that variables are identified using a dollar sign (`$(...)s`) instead of percent sign (`%(...)s`). The default format is: {{{#!ini log_format = Trac[$(module)s] $(levelname)s: $(message)s }}} In a multi-project environment where all logs are sent to the same place (e.g. `syslog`), it makes sense to add the project name. In this example we use `basename` since that can generally be used to identify a project: {{{#!ini log_format = Trac[$(basename)s:$(module)s] $(levelname)s: $(message)s }}} ---- See also: TracIni, TracGuide, TracEnvironment