Changes between Version 1 and Version 2 of TracLogging

Timestamp:

Feb 13, 2021 12:24:55 AM (4 years ago)

Author:

trac

Comment:

--

TracLogging

@@ -1 @@
-= Trac Logging =
+= Trac Logging
 [[TracGuideToc]]
 
-Trac supports logging of system messages using the standard [http://docs.python.org/lib/module-logging.html logging module] that comes with Python.
+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 trac.ini].
+Logging is configured in the `[logging]` section in [wiki:TracIni#logging-section trac.ini].
 
-== Supported Logging Methods ==
+== Supported Logging Methods
 
-The log method is set using the `log_type` configuration option, which takes any of the following values:
+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 trac.ini]. 
+ '''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 messages to local syslogd via named pipe `/dev/log`.
- '''eventlog''':: (Windows) Use the system's NT eventlog for Trac logging.
+ '''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 ==
+== Log Levels
 
-The verbosity level of logged messages can be set using the ''log_level'' directive in [wiki:TracIni trac.ini]. The log level defines the minimum level of urgency required for a message to be logged.
+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:
 
-The levels are:
  '''CRITICAL''':: Log only the most critical (typically fatal) errors.
  '''ERROR''':: Log failures, bugs and errors. 
@@ -26 +26 @@
  '''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