Recently, I have faced a limitation of WLST that does not allow you to clone a managed object (e.g. machine or server) in a script. Clone button is available in WebLogic Administration Console, but WLST lacks that convenient function. Googling didn't give much results and thus I decided to write my own script to perform this in a generic way.

First of all let's start with some setup scripts that I used on my Linux environment. For convinence purposes, I have created a script called wlst inside /usr/bin:

#!/bin/bash

. /etc/profile.d/common.sh

$JAVA_HOME/bin/java \
       -Dpython.path=/var/bea/common \
       -Dpython.cachedir=/tmp \
       -cp $WL_HOME/server/lib/weblogic.jar \
       weblogic.WLST "$@"

As you may notice it starts WLST with 2 additional properties: python.path and python.cachedir. Value given to python.path variable just specifies a directory where WLST will search for additional modules. This allows modularizing of WLST scripts and putting common functions into a common Python library. You will find more details about it later in this blog. python.cachedir is set to a directory that is writable by everyone and that keeps the cache of compiled Python scripts.

Also the common.sh script imported in the beginning just contains some common environment variable definitions reused in many of my other scripts:

...
export WL_HOME=/opt/bea/weblogic92
export NODEMGR_HOME=/var/bea/nodemanager
export JAVA_HOME=/opt/bea/jrockit-jdk1.5.0_24-R28.1.0-4.0.1
...

Now, let's look at the interesting part. The following script creates a new server and copies properties from already existing server that resides in my domain template.

############################################################
#    Name:         create_portal_domain.py
#    Version:      1.0
############################################################

import sys
from domain_functions import *

...

  cd("/")
  create('PortalServer2', 'Server')
  copyProperties(WLS,
                 'PortalServer1',
                 '/Servers',
                 'PortalServer2',
                 '/Servers',
                 ['SSL'])

...

As you can see that script calls copyProperties function that is not defined in standard WLST. The function is imported from domain_functions.py which lies in a common folder and, thanks to python.path setting, it is available to the script.

The copyProperties function looks like this:

############################################################
# Copies bean properties (offline)
############################################################
def copyProperties(wls,
                   originalBeanName,
                   originalBeanPath,
                   newBeanName,
                   newBeanPath,
                   ignoredProperties):

  wls.getCommandExceptionHandler().setMode(1)
  wls.getRuntimeEnv().set('exitonerror', 'true')

  srcPath = originalBeanPath + "/" + originalBeanName
  targetPath =  newBeanPath + "/" + newBeanName

  print "Coping properties from " +
          srcPath + " to " + targetPath
  wls.cd(srcPath)

  wls.setShowLSResult(0)
  attributes = wls.ls('a', 'true', 'a')
  children = wls.ls('c', 'true', 'c')
  wls.setShowLSResult(1)

  # Copy attributes.
  wls.cd(targetPath)
  for entry in attributes.entrySet():
    k = entry.key
    v = entry.value
    if not(k in ignoredProperties) and
       not(v is None) and
       not(v == ''):
      print "Setting property " + str(k) + " = " +
             str(v) + " on " + targetPath
      if isinstance(v, StringType):
        wls.set(k,
                v.replace(originalBeanName, newBeanName))
      else:
        wls.set(k, v)

  # Copy child bean values.
  for k in children:
    if not(k in ignoredProperties):
      srcBN = srcPath + "/" + k
      targetBN = targetPath + "/" + k
      print "Coping bean " + srcBN + "/" + originalBeanName
      print "Detected bean type as " + k
      if beanExists(wls, srcBN, "NO_NAME_0"):
        print "Changing to NO_NAME_0"
        originalBeanName = "NO_NAME_0"
        newBeanName = "NO_NAME_0"
      wls.cd(targetPath)
      wls.create(newBeanName, k)
      copyProperties(wls,
                     originalBeanName,
                     srcBN,
                     newBeanName,
                     targetBN,
                     ignoredProperties)

############################################################
# Checks bean existance.
############################################################
def beanExists(wls, path, name):
  print "Checking if bean: " + name +
         " exists in path: " + path
  wls.cd(path)
  wls.setShowLSResult(0)
  beans = wls.ls('c', 'false', 'c')
  wls.setShowLSResult(1)
  if (beans.find(name) != -1):
    print "Exists"
    return 1
  else:
    print "Doesn't exist"
    return 0

Works like a charm!