More on JavaScript and Globus GRAM

In the previous post, we looked at how to submit a job using the JavaScript CoG API (a.k.a Cyberaide JavaScript). We'll now look at the remaining parts of the job management API: listing all jobs, checking status of a particular job, listing outputs of a job, and viewing output. We'll just show the JavaScript codes and not the full HTML. The complete example is JobSubGadget.html.

As we saw last time, after a job is submitted, we are returned a job id. We actually treat all jobs as workflows, so this will be colloquially referred to as a wfid in the text. Also as we saw in the last post, all our function calls are accompanied by a callback function. JavaScript is a functional language, so you can pass functions as arguments to other functions. The recipient function then invokes your function.

Listing All Your Jobs

All of your jobs are stored persistently (using a lightweight database and the file system), so you can list all of your jobs' IDs with the function below. The callback function receives a JSON-formatted WFID list, which you can cast directly into a JavaScript variable if you choose.

/*--------------------------------------------------*/
// List jobs
/*--------------------------------------------------*/
function showJobs() {
jscog.listMyWf(listMyWfResponse);
}
//The call back.
function listMyWfResponse(jsonRet){
alert(jsonRet);
}

Checking the Status of a Particular Job

This method returns the status of a particular job as a JSON object. It takes a WFID as input. In the example, we obtain the WFID from the value of an HTML element called "wfid-status". This line of the example is not required.

/*--------------------------------------------------*/
// Check job status
/*--------------------------------------------------*/
function showStatus() {
var wfid=document.getElementById("wfid-status").value;
jscog.statusQuery(wfid,statusQueryResponse,"");
}
//The callback function.
function statusQueryResponse(jsonRet,loc) {
alert(jsonRet);
}

Listing Job Output Files

This function lists the output files associated with a particular WFID. In the previous example, this is the standard output file. Once again the output is JSON-encoded, and the input is obtained from a document element's value (wfid-list in this case). Again, this method for determining the input WFID value is only illustrative.

/*--------------------------------------------------*/
// List job output files
/*--------------------------------------------------*/
function listOutputFiles() {
var wfid=document.getElementById("wfid-list").value;
jscog.listOutput(wfid,listOutputResponse,"");
}
function listOutputResponse(jsonRet) {
alert(jsonRet);
}

Show the Output of a Job

Finally, we can view one of the output files as shown below. The return value is JSON-encoded as before.

/*--------------------------------------------------*/
// Show job output
/*--------------------------------------------------*/
function displayResult() {
var wfid=document.getElementById("wfid-display").value;
var outputfile=document.getElementById("wfid-outputfile").value;
jscog.displayResult(wfid,outputfile,fetchOutputResponse,"");
}
function fetchOutputResponse(jsonRet) {
alert(jsonRet);
}
function fetchOutputResponse(jsonRet,loc) {
alert(jsonRet);
}