Adding an embedded map "fully started" event?

[ZakarFin]

We should probably add some event/mechanism for RPC-developers to know when the map has been started as published. Currently map layers are added asynchronously (due to DescribeLayer calls etc) so they might not be on the map when the RPC-client connects to the map. One way of detecting this is polling the getAllLayers() RPC-function and comparing it to some predefined expected value, but it's not a very clean way of doing this.

Options might be something like adding a new event OR not connecting the RPC before the map is fully loaded (might be better to do this).

[ZakarFin]

Looks like getAllLayers() uses MapLayerService: https://github.com/oskariorg/oskari-frontend/blob/2.13.2/bundles/mapping/mapmodule/AbstractMapModule.js#L2324 instead of map state so it can't be used for polling. The getCurrentState() uses state so maybe that could be used for polling: https://github.com/oskariorg/oskari-frontend/blob/2.13.2/bundles/framework/rpc/instance.js#L383

• https://oskari.org/examples/rpc-api/#/MapState
• https://oskari.org/examples/rpc-api/#/MapLayers

Still not ideal.