server.js

Meteor.methods({
    convertFile:function(fileId)
    {
        var sys = Npm.require('sys'),
            fs = Npm.require('fs'),
            exec = Npm.require('child_process').exec;

            var modelObj = ModelFiles.findOne(fileId);
            var readStream = modelObj.createReadStream('modelFiles');
            var filePath = readStream.path;

            var objects;
            var mgedPath = '/usr/brlcad/dev-7.25.0/bin/mged';
            var g_objPath = '/usr/brlcad/dev-7.25.0/bin/g-obj';
            var cmd = mgedPath + " -c  " + filePath +" ls -a 2>&1";

            var uploadDirPath = filePath.substring(0, filePath.lastIndexOf("/"));
            
            /* First commmand filds the list of objects in a .g database */
            child = exec(cmd, function (error, stdout, stderr) {
                sys.print('stdout' + stdout);
                objects = stdout.split(" "); //all objects get stored in an array
                console.log(objects);
                sys.print('stderr' + stderr);

                if (error != null) {
                    console.log('exec error: ' + error);
                } else {
                    for (i in objects) {
                        /* For each object in .g database , a g file is generated */
                        var objPath = uploadDirPath + "/" + objects[i] + ".obj";
                        cmd = g_objPath + " -n 10 -o " + objPath + " " + filePath  + " " +  objects[i];
                        child = exec(cmd, function (error, stdout, stderr) {
                            if (error) {
                                console.log("There's some error in converting file" + error);
                            } else {
                                console.log("File has been converted");
                                objFS = new FS.File(objPath);
                            }
                        });
                    }
            }
        });
    }
});