Grouper Users - Open Discussion List

["Hyzer, Chris" <>]

> 
> -----Original Message-----
> From: 
> 
>  
> [mailto:]
>  
> On Behalf Of Black, Carey M.
> Sent: Monday, July 23, 2018 11:48 AM
> To: 
> 
> Subject: [grouper-users] example java code to run a bit of gsh script/JEXL?
> 
> All,
> 
> I have a use for having files of gsh scripts to do things like:
>       Establish/maintain custom:
>               Attributes Defs / AttributeName(s)
>               Folder structure
>               Groups
>               Permissions on folders/groups
>               Etc....
> 
>       However, I would also like to be able to embed/use those things 
> inside other 
>       Java code. (hooks, changelog consumer, etc...)
> 
> So I am looking for a Java code example for the following:
>       1) read a file from the file system (a gsh script) and "execute it".

I would recommend just writing in java and not calling GSH from java... all 
GSH is just java anyways...  give me a script and I will give you the java.  
Here is what you are asking for though...

This is from Grouper installer:

      if (runScript) {
        
        //running with command on command line doenst work on linux since the 
args with whitespace translate to 
        //save the commands to a file, and runt he file
        StringBuilder gshCommands = new StringBuilder();
  
        //gsh 0% GrouperSession.startRootSession()
        //edu.internet2.middleware.grouper.GrouperSession: 
6f94c99d5b0948a3be96f94f00ab4d87,'GrouperSystem','application'
        //gsh 1% // run USDU to resolve all the subjects with type=person
        //gsh 3% usdu()
  
        gshCommands.append("grouperSession = 
GrouperSession.startRootSession();\n");
        gshCommands.append("usdu();\n");
  
        File gshFile = new File(this.untarredApiDir.getAbsolutePath() + 
File.separator + "gshUsdu.gsh");
        GrouperInstallerUtils.saveStringIntoFile(gshFile, 
gshCommands.toString());
        
        List<String> commands = new ArrayList<String>();
  
        addGshCommands(commands);
        commands.add(gshFile.getAbsolutePath());
  
        System.out.println("\n##################################");
        System.out.println("Running USDU with command:\n  " + 
convertCommandsIntoCommand(commands) + "\n");
  
        GrouperInstallerUtils.execCommand(
            GrouperInstallerUtils.toArray(commands, String.class), true, 
true, null, 
           new File(this.gshCommand()).getParentFile(), null, true);
  
      }

>       2) use a gsh script as an "condition" ( AKA: if the script returns 
> "true" then 
>       keep running the java code )
>               Maybe this would be better done as a JEXL expression? 

Not sure how to get GSH return code from java... screenscrape the output?

> 
> 
> I have yet to have some time to spend on this, and I suspect the code 
> already exists. 
> I hope someone can point me at it. :)
>       I am guessing the example would be how gsh starts up and runs a file 
> would be 
>       one place.
>       And I am guessing the JEXL is "all over the place" in the code too.
> 
> Any thoughts on the performance costs of "running a gsh script" vs 
> evaluating JEXL 
> expressions?

JEXL is fast, running an external GSH is slow.  Java would be fast though as 
I suggested above

> 
> But maybe I am going about initialization type functions the hard way? 
> Are there other facilities for this general kind of function?
> 
> -- 
> Carey Matthew 
> 
>

-----Original Message-----
From: 

 
[mailto:]
 On Behalf Of Black, Carey M.
Sent: Monday, July 23, 2018 11:48 AM
To: 

Subject: [grouper-users] example java code to run a bit of gsh script/JEXL?

All,

I have a use for having files of gsh scripts to do things like:
        Establish/maintain custom:
                Attributes Defs / AttributeName(s)
                Folder structure
                Groups
                Permissions on folders/groups
                Etc....

        However, I would also like to be able to embed/use those things 
inside other Java code. (hooks, changelog consumer, etc...)

So I am looking for a Java code example for the following:
        1) read a file from the file system (a gsh script) and "execute it".
        2) use a gsh script as an "condition" ( AKA: if the script returns 
"true" then keep running the java code )
                Maybe this would be better done as a JEXL expression? 


I have yet to have some time to spend on this, and I suspect the code already 
exists. I hope someone can point me at it. :)
        I am guessing the example would be how gsh starts up and runs a file 
would be one place.
        And I am guessing the JEXL is "all over the place" in the code too.

Any thoughts on the performance costs of "running a gsh script" vs evaluating 
JEXL expressions?

But maybe I am going about initialization type functions the hard way? 
Are there other facilities for this general kind of function?

-- 
Carey Matthew