Drop columns from key table

Author: georgecwan

web/client-api/src/main/java/io/deephaven/web/client/api/JsPartitionedTable.java

@@ -10,6 +10,7 @@
 import io.deephaven.javascript.proto.dhinternal.io.deephaven.proto.partitionedtable_pb.GetTableRequest;
 import io.deephaven.javascript.proto.dhinternal.io.deephaven.proto.partitionedtable_pb.MergeRequest;
 import io.deephaven.javascript.proto.dhinternal.io.deephaven.proto.partitionedtable_pb.PartitionedTableDescriptor;
+import io.deephaven.javascript.proto.dhinternal.io.deephaven.proto.table_pb.DropColumnsRequest;
 import io.deephaven.javascript.proto.dhinternal.io.deephaven.proto.ticket_pb.TypedTicket;
 import io.deephaven.web.client.api.barrage.WebBarrageUtils;
 import io.deephaven.web.client.api.barrage.def.ColumnDefinition;
@@ -23,6 +24,7 @@
 import io.deephaven.web.shared.data.RangeSet;
 import io.deephaven.web.shared.fu.JsConsumer;
 import jsinterop.annotations.JsIgnore;
+import jsinterop.annotations.JsMethod;
 import jsinterop.annotations.JsProperty;
 import jsinterop.annotations.JsType;
 import jsinterop.base.Js;
@@ -284,13 +286,21 @@ public Column[] getColumns() {
     }
 
     /**
-     * A Table object containing all currently known keys used for this partitioned table.
+     * Fetch a table containing all the valid keys of the partitioned table.
      *
-     * @return Table
+     * @return Promise of a Table
      */
-    @JsProperty
-    public JsTable getKeyTable() {
-        return keys;
+    @JsMethod
+    public Promise<JsTable> getKeyTable() {
+        return connection.newState((c, state, metadata) -> {
+            DropColumnsRequest drop = new DropColumnsRequest();
+            drop.setColumnNamesList(new String[]{descriptor.getConstituentColumnName()});
+            drop.setSourceId(keys.state().getHandle().makeTableReference());
+            drop.setResultId(state.getHandle().makeTicket());
+            connection.tableServiceClient().dropColumns(drop, metadata, c::apply);
+        }, "drop constituent column")
+                .refetch(this, connection.metadata())
+                .then(state -> Promise.resolve(new JsTable(connection, state)));
     }
 
     /**