Linux Directory Tree

Problem Statement
Print a tree structure showing all the files and directories under the current directory.

Solution
 find ./ | sed -e 's/[^-][^\/]*\//--/g;s/--/ |-/'

CRONTAB - Quick Reference

Crontab Commands

crontab -e	Edit your crontab file, or create one if it doesn’t already exist.
crontab -l	Display your crontab file.
crontab -r	Remove your crontab file.

Crontab syntax
A crontab file has five fields for specifying day , date and time followed by the command to be run at that interval.

*     *     *   *    *        command to be executed
-     -     -   -    -
|     |     |   |    |
|     |     |   |    +----- day of week (0 - 6) (Sunday=0)
|     |     |   +------- month (1 - 12)
|     |     +--------- day of month (1 - 31)
|     +----------- hour (0 - 23)
+------------- min (0 - 59)

The value column can have a * or a list of elements separated by commas. An element is either a number in the ranges shown above or two numbers in the range separated by a hyphen (meaning an inclusive range).
  
Crontab Example
A line in crontab file like below removes the tmp files from /home/someuser/tmp each day at 6:30 PM.

     30     18     *     *     *         rm /home/someuser/tmp/*
  
Disable Email
By default cron jobs sends a email to the user account executing the cronjob. If this is not needed put the following command At the end of the cron job line.
 
    >/dev/null 2>&1

Generate log file
To collect the cron execution execution log in a file :
 
    30 18 * * * rm /home/someuser/tmp/* > /home/someuser/cronlogs/clean_tmp_dir.log

Adhoc Service Call in IBM BPM 7.5

Problem Statement 

You want to call a service residing outside of your toolkit/process-app. You know the name of the service, the process-app/toolkit acronym and possibly the snapshot name as well. You want to discover the service and execute it without having to go through the process of creating dependencies within your toolkit/process-app. Traditionally this is not possible, IBM BPM 7.5 provides API to call any service from JavaScript (Using tw.system.executeServiceByName()), but this can only execute the services that directly belong to the process-app/toolkit or any dependent toolkit(s). We want to break free of this limitation and execute any service on the environment.

Solution

Create a new Server-JS file and copy the following functions into it.

function findSnapshotForProcessApp(processApp, snapshotName) {
    var processAppObj = null;
    if(typeof processApp == 'string')
        processAppObj = tw.system.model.findProcessAppByAcronym(processApp);

    try {
        if(snapshotName) {
            return processAppObj.findSnapshotByName(snapshotName);
        }
        else {
            var snaps = processAppObj.snapshots;
            if(snaps && snaps.length > 0)
                return snaps[snaps.length -1];
            else
                return null;
        }
    }
    catch (e) {
      throw 'Error in findSnapshotForProcessApp : Required parameter "processApp" not provided or an invalid process-app acronym was provided.';
    }
}

function executeServiceByNameAdHoc(serviceName, inputParams, processApp, snapshotName) {
    var snapshot = findSnapshotForProcessApp(processApp, snapshotName);
   
    if(snapshot) {
        var serv = snapshot.findServiceByName(serviceName);
        if(serv) {
            return serv.execute(inputParams);
        }
        else // Service not found
           throw 'Error in executeServiceByNameAdHoc : No service found. Parameters provided : processApp=' + processApp + ", snapshotName=" + snapshotName + ", serviceName=" + serviceName;
       
    }
    else // Snapshot not found
        throw 'Error in executeServiceByNameAdHoc : No snapshot found. Parameters provided : processApp=' + processApp + ", snapshotName=" + snapshotName;
}

Call the function executeServiceByNameAdHoc with the following parameters to execute any adhoc service.

* @param {String} serviceName The name of the service to execute
* @param {Map} inputValues the input values for the service
* @param {String} processApp : The Acronym for the process app in which the service resides.
* @param {String} (OPTIONAL) snapshotName : Name of the specific snapshot version to execute the service from.
*
* @return A map of output values
* @type Map
Issues

If you get a "ConcurrentModificationException" while trying to execute a service with multiple parameters, the go ahead and deploy the IBM APAR JR49178. This fixes a bug related to HashMap in the method com.lombardisoftware.core.script.js. TWServiceScriptable.jsFunction_execute(Object)

Update group membership of a user

Use the following steps to synchronize group membership of any user, connected to external directory services (LDAP, eDirectory) :

var sec = Packages.com.lombardisoftware.client.delegate.SecurityDelegateFactory.getInstance().newInstance();
sec.updateGroupMembership(tw.local.userId);