How can I append to sys.path using Weblogic Scripting Tools?

Question

I need to logically and non-interactively undeploy an application from Oracle 10. The solution I came up with is to use WLST and write a python program to do the work for me. The problem I have is in manipulating sys.path outside of the script.

I'm invoking my script using Weblogic's custom WLSTTask Ant task and passing certain arguments into the script via the arguments attribute. It looks like this:

<target name="undeploy-oldest">
    <wlsttask
      debug="true"
      fileName="${basedir}/resources/script/py/undeployOldestApp.py"
      arguments="dmi ${user} ${password} ${url} ${basedir}/resources/script/py/" />
</target>

And the script itself.

import sys
from apputil.applist import getAppList
from apputil.apputility import getOldestAppVersion
from wlstModule import connect, disconnect, undeploy

appName = sys.argv[1]
username = sys.argv[2]
password = sys.argv[3]
url = sys.argv[4]

connect(username, password, url)
serverAppList = getAppList()
versionToUndeploy = getOldestAppVersion(appName, serverAppList)
if (versionToUndeploy != -1):
    undeploy(versionToUndeploy)
    print "Undeployed " + versionToUndeploy
else:
    print "Nothing to undeploy"
disconnect()

The problem I'm having has to do with the last argument in the Ant task's arguments list. I was under the impression that Jython adds the current working directory to sys.path automatically; though, while I see an entry for "." in sys.path, the imports from my custom apputil module do not work. I suspect this has to do with where Ant is actually running from and that "." doesn't represent the directory in which undeployOldestApp.py exists. I tried adding the path to the Ant classpath with a classpath tag inside the WLSTTask tag, but it didn't add that path to Jython's sys.path list.

My only success so far has been in that last argument in the Ant task, where in between import sys and from apputil.applist import getAppList I call sys.path.append(sys.argv[5]). My scripts are then referenced properly from the import and all is well. My preference would be that I eliminate this dependency and that the Ant task would handle injection of the desired path element. I have had no luck accomplishing this.

I hope I've been clear, and that the community will ahve some novel suggestions or at least explanations for why this doesn't seem to work. Thanks.

I am not trying to answer your exact question, but a suggestion to make your script robust. Your script can be called from anywhere and not necessarily from the directory where it is present. So its always a good habit to determine your module location dynamically in the script and add sys.path. For example if your module location is the same as the script location (In your case it is.), then you just need to determine script location and append to sys.path this way you would avoid param 5 as well. I know its an old post, just sharing my thoughts :) — Mani, Sep 26 '12 at 11:34

score 0 · Answer 1 · answered Sep 26 '11 at 09:29

Maybe you could use the executeScriptBeforeFile="true" parameter and

<script>
    sys.path.append(...)
</script>

Alternatively, you might try to run the task from java:

<java classname="weblogic.WLST" fork="true">
    <arg line="${basedir}/resources/script/py/undeployOldestApp.py dmi ${user} ${password} ${url} ${basedir}/resources/script/py/"/>
    <classpath refid="class.path"/>
</java>

This might give you access to some parameters of the java task that are not available on the wlsttask one.

How can I append to sys.path using Weblogic Scripting Tools?

1 Answers1