Angular: Push Generated Timestamp on Submitted Form - json

Question

I've written a form in Angular that sends submitted data in my form to an object called places in my Firebase.
HTML
<form role="form" name="addPlaceForm" ng-submit="createHospital(newHospital)">
<input type="text" placeholder="Enter title here" ng-model="newHospital.title">
<button type="submit" class="btn btn-primary btn-lg">Submit</button>
</form>
JS
var rootRef = new Firebase('URL');
var placesRef = rootRef.child('places');
function createHospital(hospital) {
placesRef.push(hospital);
}
Is there a way I can push a generated timestamp called created_at to my places object when it's submitted?
"created_at" : "2014-07-15T01:52:33Z"
And what about other automated data, like pushing a unique ID, for example.
Any help with this would be appreciated. Thanks in advance!

Answer 1

Is there a way I can push a generated timestamp called created_at to my places object when it's submitted?
An alternative to passing the timestamp from the client is to use Firebase's built-in Firebase.ServerValue.TIMESTAMP, which is documented as:
A placeholder value for auto-populating the current timestamp (time since the Unix epoch, in milliseconds) by the Firebase servers.
So you could do something like this:
function createHospital(hospital) {
hospital.created_at = Firebase.ServerValue.TIMESTAMP;
placesRef.push(hospital);
}
See this post for more information:https://www.firebase.com/blog/2013-06-17-howto-build-a-presence-system.html
What about other automated data, like pushing a unique ID?
When you call the Firebase push method a unique ID is already generated for you. The documentation for push:
Generates a new child location using a unique name and returns a Firebase reference to it.
This ID is guaranteed by Firebase to be unique, specifically so that your application doesn't have to worry about it. The push-generated ID takes a form like -JXd1pbUU89Xbd4BYvx6, -JZoLcBKnd1A8Gn-ZP0I, etc.
I would recommend sticking to that ID, instead of generating your own additional ID. If you prefer to to generate your own IDs, I would solely use that ID and use it to name your node instead of letting push generate one for you:
var newID = ID_GENERATE_FUNCTION();
placesRef.child(newID).set(hospital);
Note that here too I don't store the newID in the hospital object.

Answer 2

Right when you add the hospital to the array you can create the two parameters you want:
function createHospital(hospital) {
var newHospital = angular.copy(hospital);
newHospital.created_at = new Date();
newHospital.ID = ID_GENERATE_FUNCTION();
placesRef.push(newHospital);
}