Refactor into initialize function

Author: kylebarron

src/index.tsx

@@ -1,13 +1,13 @@
 import * as React from "react";
 import { useState, useEffect } from "react";
 import { createRender, useModelState, useModel } from "@anywidget/react";
-import type { Initialize, Render } from "@anywidget/types";
+import type { Initialize, InitializeProps, Render } from "@anywidget/types";
 import Map from "react-map-gl/maplibre";
 import DeckGL from "@deck.gl/react/typed";
 import { MapViewState, type Layer } from "@deck.gl/core/typed";
 import { BaseLayerModel, initializeLayer } from "./model/index.js";
 import type { WidgetModel } from "@jupyter-widgets/base";
-import { useParquetWasm } from "./parquet.js";
+import { initParquetWasmFromBinary } from "./parquet.js";
 import { getTooltip } from "./tooltip/index.js";
 import { isDefined, loadChildModels } from "./util.js";
 import { v4 as uuidv4 } from "uuid";
@@ -63,10 +63,6 @@ async function getChildModelState(
 function App() {
   let model = useModel();
 
-  let [parquetWasmBinary] = useModelState<DataView | null>(
-    "_parquet_wasm_content",
-  );
-  let [parquetWasmReady] = useParquetWasm(parquetWasmBinary);
   let [mapStyle] = useModelState<string>("basemap_style");
   let [mapHeight] = useModelState<number>("_height");
   let [showTooltip] = useModelState<boolean>("show_tooltip");
@@ -110,15 +106,7 @@ function App() {
   let [stateCounter, setStateCounter] = useState<Date>(new Date());
 
   useEffect(() => {
-    if (!parquetWasmReady) {
-      return;
-    }
-
     const callback = async () => {
-      if (!parquetWasmReady) {
-        throw new Error("inside callback but parquetWasm not ready!");
-      }
-
       const childModels = await loadChildModels(
         model.widget_manager,
         childLayerIds,
@@ -132,7 +120,7 @@ function App() {
       setSubModelState(newSubModelState);
     };
     callback().catch(console.error);
-  }, [parquetWasmReady, childLayerIds]);
+  }, [childLayerIds]);
 
   const layers: Layer[] = [];
   for (const subModel of Object.values(subModelState)) {
@@ -200,7 +188,13 @@ function App() {
   );
 }
 
+async function initialize({ model }: InitializeProps): Promise<void> {
+  const parquetWasmBinary: DataView = model.get("_parquet_wasm_content");
+  await initParquetWasmFromBinary(parquetWasmBinary);
+}
+
 const module: { render: Render; initialize?: Initialize } = {
+  initialize,
   render: createRender(App),
 };
 

src/parquet.ts

@@ -1,4 +1,3 @@
-import { useEffect, useState } from "react";
 import { initSync, readParquet } from "parquet-wasm/esm/arrow2";
 import * as arrow from "apache-arrow";
 
@@ -17,20 +16,13 @@ async function decompressBlob(blob: Blob) {
  *
  * @return Whether initialization succeeded
  */
-export async function initParquetWasmFromBinary(
-  view: DataView | null,
-): Promise<boolean> {
-  if (!view) {
-    return false;
-  }
-
+export async function initParquetWasmFromBinary(view: DataView): Promise<void> {
   let blob = new Blob([view]);
   const decompressedBlob = await decompressBlob(blob);
   const decompressedBuffer = await decompressedBlob.arrayBuffer();
 
   initSync(decompressedBuffer);
   WASM_READY = true;
-  return true;
 }
 
 /**
@@ -74,21 +66,3 @@ export function parseParquetBuffers(dataViews: DataView[]): arrow.Table {
 
   return new arrow.Table(batches);
 }
-
-export function useParquetWasm(view: DataView | null): [boolean] {
-  const [wasmReady, setWasmReady] = useState<boolean>(false);
-
-  // Init parquet wasm
-  useEffect(() => {
-    const callback = async () => {
-      const succeeded = await initParquetWasmFromBinary(view);
-      if (succeeded) {
-        setWasmReady(true);
-      }
-    };
-
-    callback();
-  }, []);
-
-  return [wasmReady];
-}