Fixed async loading of node.js module

packages/perspective/src/js/API/client.js

@@ -95,13 +95,19 @@ Client.prototype._handle = function(e) {
             window.dispatchEvent(event);
             _initialized = true;
         }
-        for (var m in this._worker.messages) {
-            if (this._worker.messages.hasOwnProperty(m)) {
-                this._worker.messages[m]();
-            }
-        }
+
+        const msgs = this._worker.messages;
+
         this._worker.initialized.value = true;
         this._worker.messages = [];
+
+        if (msgs) {
+            for (const m in msgs) {
+                if (msgs.hasOwnProperty(m)) {
+                    setTimeout(msgs[m]);
+                }
+            }
+        }
     }
     if (e.data.id) {
         var handler = this._worker.handlers[e.data.id];

packages/perspective/src/js/perspective.node.js

@@ -29,18 +29,21 @@ const wasm = require("./psp.async.wasm.js");
 
 const buffer = fs.readFileSync(path.join(__dirname, wasm)).buffer;
 
-const sync_module = perspective(
-    load_perspective({
-        wasmBinary: buffer,
-        wasmJSMethod: "native-wasm"
-    })
-);
-
 const SYNC_SERVER = new (class extends Server {
+    init(msg) {
+        load_perspective({
+            wasmBinary: buffer,
+            wasmJSMethod: "native-wasm"
+        }).then(core => {
+            this.perspective = perspective(core);
+            this.post(msg);
+        });
+    }
+
     post(msg) {
         SYNC_CLIENT._handle({data: msg});
     }
-})(sync_module);
+})();
 
 const SYNC_CLIENT = new (class extends Client {
     send(msg) {
@@ -51,7 +54,7 @@ const SYNC_CLIENT = new (class extends Client {
 SYNC_CLIENT.send({id: -1, cmd: "init"});
 
 module.exports = SYNC_CLIENT;
-module.exports.sync_module = () => sync_module;
+module.exports.sync_module = () => SYNC_SERVER.perspective;
 
 let CLIENT_ID_GEN = 0;
 

packages/perspective/test/js/internal.js

@@ -15,18 +15,20 @@ const arrow = fs.readFileSync(path.join(__dirname, "..", "arrow", "test-null.arr
 var arrow_psp_internal_schema = [9, 10, 1, 2, 3, 4, 11, 19, 19, 12, 12, 12, 2];
 
 module.exports = (perspective, mode) => {
-    // Get the internal module;
-    if (perspective.sync_module) {
-        perspective = perspective.sync_module();
-    }
-
     describe("Internal API", function() {
         it("is actually using the correct runtime", async function() {
+            // Get the internal module;
+            if (perspective.sync_module) {
+                perspective = perspective.sync_module();
+            }
             expect(perspective.__module__.wasmJSMethod).toEqual(mode === "ASMJS" ? "asmjs" : "native-wasm");
         });
 
         it("Arrow schema types are mapped correctly", async function() {
             // This only works for non parallel
+            if (perspective.sync_module) {
+                perspective = perspective.sync_module();
+            }
             var table = perspective.table(arrow.slice());
             let schema, stypes;
             let types = [];

packages/perspective/test/js/sync_load.spec.js

@@ -0,0 +1,16 @@
+/******************************************************************************
+ *
+ * Copyright (c) 2017, the Perspective Authors.
+ *
+ * This file is part of the Perspective library, distributed under the terms of
+ * the Apache License 2.0.  The full license can be found in the LICENSE file.
+ *
+ */
+
+describe("perspective.js module", function() {
+    it("does not access the WASM module until it is ready", async () => {
+        const tbl = require("../../build/perspective.node.js").table([{x: 1}]);
+        const size = await tbl.size();
+        expect(size).toEqual(1);
+    });
+});