fixup: prevent to reload a datalayer after other peer has saved it

The scenario to reproduce is:
- peer A creates a datalayer
- peer B add a marker on that datalayer
- peer B saves the datalayer

Before this fix, after the save, peer A would get a new _referenceVersion
for this datalayer, and the render method would make a hide/show,
which would refetch the data from the server, duplicating it.
So forcing the _loaded to be true in this situation prevent this.

We may want to rework the "_loaded" pattern, maybe with the server
returning in a datalayer metadata the length of the data it get for
this given datalayer, so the client knows if it is worth getting
data for a layer when itself (the client) does not have any.

Co-authored-by: David Larlet <david@larlet.fr>

umap/static/umap/js/modules/sync/updaters.js

@@ -63,6 +63,7 @@ export class DataLayerUpdater extends BaseUpdater {
   update({ key, metadata, value }) {
     const datalayer = this.getDataLayerFromID(metadata.id)
     if (fieldInSchema(key)) {
+      datalayer._loaded = true
       this.updateObjectValue(datalayer, key, value)
     } else {
       console.debug(
@@ -92,7 +93,7 @@ export class FeatureUpdater extends BaseUpdater {
   upsert({ metadata, value }) {
     const { id, layerId } = metadata
     const datalayer = this.getDataLayerFromID(layerId)
-    const feature = this.getFeatureFromMetadata(metadata, value)
+    const feature = this.getFeatureFromMetadata(metadata)
 
     if (feature) {
       feature.geometry = value.geometry
@@ -109,7 +110,7 @@ export class FeatureUpdater extends BaseUpdater {
       return
     }
     if (key === 'geometry') {
-      const feature = this.getFeatureFromMetadata(metadata, value)
+      const feature = this.getFeatureFromMetadata(metadata)
       feature.geometry = value
     } else {
       this.updateObjectValue(feature, key, value)

umap/tests/integration/test_websocket_sync.py

@@ -421,9 +421,11 @@ def test_should_sync_datalayers(new_page, asgi_live_server, tilelayer):
         1
     ).click()
 
-    # Now peerA saves the layer 2 to the server
+    # Peer A should not be in dirty state
-    with peerA.expect_response(re.compile(".*/datalayer/update/.*")):
+    expect(peerA.locator("body")).not_to_have_class(re.compile(".*umap-is-dirty.*"))
-        peerA.get_by_role("button", name="Save").click()
+
+    # Peer A should only have two markers
+    expect(peerA.locator(".leaflet-marker-icon")).to_have_count(2)
 
     assert DataLayer.objects.count() == 2