Password authentification for as3 php upload

Question

Hi
I'm making an Air file that uploads and overwrites an XML file.
So far, the php is very simple:
$everything = $_POST['saveThisXML'];
  $everything = stripslashes($everything);
   $toSave = $everything; 
   $fp = fopen("settings.xml", "w");
   if(fwrite($fp, $toSave)) echo "writing=Ok";
   else echo "writing=Error";
   fclose($fp);
I'd like to set up a user name and passowrd that the user enters in the Air app.  Is it then just a matter of sending POST data to the php file, and have it check the user and pass variables?  Is that a reasonably safe way to do it?  If not, can someone please point me in th edirection of a good tutorial that they're used on this topic?
Thanks again guys.
Shaun

Answer 1

OK
So somewhere along the line, the user is going to have to set up a database.  I can use PHP to do that though, right?  And they'd just have to run the php page once to set it up.
Thanks kglad.
Also, I can successfully upload data from a string (myString) in Flash using PHP:
var myData:URLRequest = new URLRequest("http://www.blah.com/saver.php");
        myData.method = URLRequestMethod.POST;
        var variables:URLVariables = new URLVariables();
        var origEverything:String = myString;
        variables.saveThisXML = origEverything;       
        myData.data = variables;
        var loadData:URLLoader = new URLLoader();
        loadData.dataFormat = URLLoaderDataFormat.VARIABLES;
        loadData.addEventListener(Event.COMPLETE, doneBaby);
        loadData.addEventListener(IOErrorEvent.IO_ERROR, dataLoadError);
        loadData.load(myData);  
However, when I try to add two variables to send to php, I get a named pairs error.  Here's what I tried adding (in bold):
var myData:URLRequest = new URLRequest("http://www.blah.com/saver.php");
         myData.method = URLRequestMethod.POST;
         var variables:URLVariables = new URLVariables();
         var origEverything:String = myString;
          var passTest:String = 'testPW';
         variables.saveThisXML = origEverything;     
     variables.saveThisPass = passTest;     
        myData.data = variables;
         var loadData:URLLoader = new URLLoader();
         loadData.dataFormat = URLLoaderDataFormat.VARIABLES;
         loadData.addEventListener(Event.COMPLETE, doneBaby);
         loadData.addEventListener(IOErrorEvent.IO_ERROR, dataLoadError);
         loadData.load(myData);  
Why would that generate an error?
Cheers kglad
Shaun