load annotations incrementally (#1107)

* load annotations individually

* fix type check to be more general

* update node CI version from 10 to 12

* node 11

* debug print node version

* travis node version to latest

* try nvm

* remove extraneous node_js statement

* remove node version debugging printf

* incrementally load all annotations and layout

* process annotations and layout as they are loaded

* fix tests

* sort categories incrementally

* incrementally build category view summary; add category loading spinner

* add spinner to continuous metadata

* configure undoable reducer

* incremental crossfilter creation

* improve busy layout

* more layout cleanup

* correctly reconcile categories in schema

* refine layout of lsb spinners

* more spinner layout work

* more spinner layout

* always load layout before obs annotations

client/src/reducers/controls.js

@@ -41,8 +41,31 @@ const Controls = (
     case "initial data load start": {
       return { ...state, loading: true };
     }
+    case "universe: column load success": {
+      /* 
+      we are in a loading state until the following are true:
+        * universe exists (if partially)
+        * embeddings (obsLayout) are loaded
+        * varAnnotations index is loaded
+      */
+      const universeExists = !!nextSharedState.universe;
+      const embeddingsExist =
+        !nextSharedState.universe?.obsLayout?.isEmpty() ?? false;
+      const varIndex = nextSharedState.universe.schema.annotations.var.index;
+      const varAnnotationsIndexExists =
+        universeExists &&
+        nextSharedState.universe.varAnnotations.hasCol(varIndex);
+      return {
+        ...state,
+        loading: !(
+          universeExists &&
+          embeddingsExist &&
+          varAnnotationsIndexExists
+        )
+      };
+    }
     case "initial data load complete (universe exists)": {
-      /* first light - create world & other data-driven defaults */
+      /* now fully loaded */
       return {
         ...state,
         loading: false,