Logging

Latest revision as of 19:54, 10 July 2008

[edit] Access logging

Main article: access-log

An access log receives output describing each request received by the server. It is commonly used in conjunction with analysis tools to determine statistics and patterns of use for a website.

See the main page for a description of all available configuration settings.

[edit] Examples

<access-log path="logs/access.log"
            format='%h %l %u %t "%r" %s %b "%{Referer}i" "%{User-Agent}i"'
            rollover-period="1W"/>

<access-log path="logs/access.log"
            format='%h %l %u %t "%r" %s %b "%{Referer}i" "%{User-Agent}i"'
            rollover-size="1mb"/>

[edit] stdout-log and stderr-log

Main article: stdout-log

Main article: stderr-log

The stdout-log and stderr-log directives capture and redirect the output of System.out and System.err.

[edit] Examples

resin.conf configuration to capture System.out and System.err output to log files.

<resin xmlns="http://caucho.com/ns/resin"
       xmlns:resin="http://caucho.com/ns/resin/core">

  <stdout-log path='/var/log/foo/stdout.log'
              rollover-period='1W'/>
  <stderr-log path='/var/log/foo/stderr.log'
              rollover-period='1W'/>
 
  ...

[edit] log

Main article: log

Java programs (including Resin) can use the logging facilities included in the JDK. Log messages have a name and and a level.

Logging can be used to enable Resin logging names and to enable application specific logging that utilizes the JDK logging facilities.

[edit] Examples

resin.conf configuration to capture finer logging and display it on the console, useful during development:

<resin xmlns="http://caucho.com/ns/resin"
       xmlns:resin="http://caucho.com/ns/resin/core">
  ...
  <log name="" level="finer" path="stdout:"/>
  ...
</resin>

resin.conf configuration to capture finer request and response related logging from Resin, and all logging from the com.hogwarts application under development:

<resin xmlns="http://caucho.com/ns/resin"
       xmlns:resin="http://caucho.com/ns/resin/core">
 
  <log path='stdout:' timestamp='[%H:%M:%S.%s] '>
    <logger name="com.caucho.server.port.TcpConnection" level="fine"/>
    <logger name="com.caucho.server.http.HttpRequest" level="fine"/>
    <logger name="com.caucho.server.connection.AbstractHttpResponse" level="fine"/>
 
    <logger name="com.hogwarts" level="all"/>
  </log>
 
  ...
  
</resin>

[edit] Archiving

All log directives support archiving, when the log reaches a certain size or age a rollover occurs and the existing log is saved away while a new log is started.

path-format and archive-format are two mutually exclusive methods for archiving logs. Rollover determines the frequency at which the archive files are created.

[edit] path-format

path-format specifies the name of a file. The name contains date format escape sequences that are replaced with the current date and time. When the rollover occurs, a new file is started with the appropriate date and time. Thus path-format results in archive files that are named with the date and time of the first entry in the log.

...
<host id="www.foo.com">
   <access-log path-format="/var/www/log/%Y/%m/%d.access.log"
               rollover-period="1D"/>
   ... 
</host>
...

[edit] archive-format and path

Log messages are written to the file specified by path. When a rollover occurs the contents of the file are copied to the archive-path. The archive-path contains date format escape sequences that are replaced with the current date and time. Thus archive-format results in log files that are named with the date and time of the last entry in the log.

archive-format can use a *.gz or *.zip extension to indicate that the archived log should be compressed.

<access-log path="log/access.log"
            archive-path="/var/www/log/access.log.%Y%m%d.gz"
            rollover-period="1D"/>

[edit] Rollover

The fequency of the rollover is is specified with rollover-period or rollover-size.

rollover-period is a time based specification of a period in days (15D), weeks (2W), months (1M), or hours (1h). When the specified time period has elapsed the rollover occurs.

rollover-size is a size based specification of a size in bytes (50000), kb (128kb), or megabytes (10mb). When the log reaches the specified size the rollover occurs.

[edit] Disabling rollover

To completely disable rollovers, set the rollover-size to such a high number that it will never occur:

 <stdout-log path="log/stdout.log" rollover-size="1024mb"/>