InDesign server: How to detect or stop execution when a file needs plugins that are not installed

After communicating with Adobe-Support, they helped find a workaround to reliably detect any errors occured after opening.

They provided the following example:

//Turn on Error List
app.serverSettings.useErrorList = true;

//Open test doc
var myDoc = app.open(File("/C/PATH/TO/FILE/example.indd"));

//Check error list
for (i=0; i < app.errorListErrors.count();i++)
{
//write out the error time and error string
$.writeln(app.errorListErrors.item(i).listErrorTime + " " + app.errorListErrors.item(i).listErrorMessage);
}

//Clear the error list
app.clearAllErrors();

//Close test doc
myDoc.close();

Which i modified to this:

//Turn on Error List
app.serverSettings.useErrorList = true;

//Open doc
var myDoc = app.open(File("/C/PATH/TO/FILE/example.indd"));

//Abort if at least one error occured (log level "ERROR")
for (i=0; i < app.errorListErrors.count();i++)
{
    if (app.errorListErrors.item(i).listErrorLevel === 3) {
        throw new Error("Document opened with at least one error.");
    }
}

// Turn off error list
app.serverSettings.useErrorList = false;

// Go on with script...

I iterate over all errors and check if at least one is logged with the log level 3 (ERROR). I do this because this list also contains warnings (log level 2, e. g. missing fonts/images) but i do not want to abort in these cases.

Best regards,

Dean