Firebase get full path of reference URL in dataSnapshot (javascript API)

Question

Say I have the following:

var firebaseARef = new Firebase("http://this.is.my/firebase/url/A/reference")
var firebaseBRef = new Firebase("http://this.is.my/firebase/url/B/reference")

When I define my .on() functions, I'd like to specify a single handler, and then do all of the handling in one place in my code, rather than having to define the functions inline with the .on() definition. To illustrate:

var handleAllFirebaseStuff = function(dataSnapshot){
    var name = dataSnapshot.name(); //PROBLEM HERE: returns "reference", no way to distinguish!
    switch(name){
       case "http://this.is.my/firebase/url/A/reference": //How do I get this full reference from dataSnapshot?
          /* do stuff for A reference */
       case "http://this.is.my/firebase/url/B/reference": //How do I get this full reference from dataSnapshot?
          /* do stuff for B reference */
       default:
          break;
    }
}

firebaseARef.on('value', handleAllFirebaseStuff);
firebaseBRef.on('value', handleAllFirebaseStuff);

The problem is dataSnapshot.name() will only return "reference" in both cases, making it impossible to distinguish between the two references in the switch/case statement!

I'm certain that dataSnapshot contains this information somewhere, but I have yet to uncover it in any convenient fashion. Exploring the dataSnapshotobject in the console, I find that there is an object buried within called path that contains (among other things) an array, using the example above, that would contain ["firebase", "url", "A", "reference"], but there is no easy way to access it.

If I had access to that array, I could rebuild the URL or find a more convenient way to handle the switch/case statement. I think a full string of the reference would be more appropriate as an easily accessible value from dataSnapshot.

Solution

To get back from a Snapshot to the full URL, you do:

snapshot.ref().toString()

The toString part is somewhat counter-intuitive. I often find myself having to test it, to see if that's indeed the way to go.

hint It would be nice if there was also a more explicit getUrl method hint

UPDATE:

With recent SDK versions ref is no longer a function, so you'll have to use:

snapshot.ref.toString();

Comments

[MandM]

Yes! The API documentation for DataSnapshot.ref() in it's entirety is, "The Firebase reference for the location that generated this DataSnapshot." There is obviously more buried in here (i.e. .ref().toString()) -- let's see some more documentation! (or more helpful explicit methods hint hint)

[MandM]

Also, I'm glad that toString() works, but it being an undocumented method slightly scares me -- what if the method is totally changed in functionality between Firebase revs? (There is no guarantee it wont!) So, I agree with your statement about explicit method wholeheartedly - Firebase oughta move on this.

[Frank van Puffelen]

The fact that ref.toString() returns the full URL is documented: firebase.com/docs/web/api/firebase/tostring.html "Gets the absolute URL corresponding to this Firebase reference's location."

[Matt Jensen]

If you want the relative path use: snapshot.ref.path.toString();