GeoJson provider and real time entity updates

Dear All,

I was wondering if there is any particular reason why the GeoJson data source does not allow to update its entities on the fly?

The CZML data source has an handy “process” method which does not remove all the entities within the data source before processing the new ones,
while the GeoJSON data source has no such method (just “load”).

I’ve modified Cesium in a few places to allow this behaviour, and I was wondering if it could be of any use to the community.


There’s no particular reason other than we didn’t have a use case for it. It should be as easy as adding process and processUrl functions in GeoJsonDataSource.js. We’d be happy to take a pull request if you want to open one.

Is this still in the works ? This is definitely something that GeoJson and KML can benefit from.

Can you please help me understand what your use case is?

KML has built in mechanisms for dealing with updates, for this reason each KML file needs to be treated independently. You can load multiple documents side-by-side easily, but trying to combine two documents (merging common data) isn’t something the spec is built for.

GeoJSON has no real mechanism for updates. Like KML, if you’re goal is to load multiple documents, that’s easy. If you’re goal is to update an existing GeoJSON document with another GeoJSON document, I’d need to better understand the use case and how something like that is structured on the data side. GeoJSON has no way in the spec to uniquely identify a given object, so updating it with another file may be a non-starter.

Hi Matthew
AS you said,

"KML has built in mechanisms for dealing with updates, for this reason each KML file needs to be treated independently".

So my requirement is, how to updates my kml on every few seconds it should feel like real time data is showing up.
like this -

Also where can i get code for link above.

Thanks in advance.


Is there any solution for this issue, I am loading only once the feature collection and I want to only update/add one entity according to a given geojson (like process in czml).



Hi there,

Unfortunately, we don’t yet have support for this.


  • Rachel