Move download-assets.js to root directory

scripts/download-assets.js

@@ -0,0 +1,44 @@
+const tar = require("tar");
+const fs = require("fs");
+
+const NPM_URL = "https://registry.npmjs.org";
+const ROOT = "public/assets";
+
+const FFMPEG_VERSION = "0.12.2";
+const UTIL_VERSION = "0.12.0";
+const CORE_VERSION = "0.12.1";
+
+const FFMPEG_TGZ = `ffmpeg-${FFMPEG_VERSION}.tgz`;
+const UTIL_TGZ = `util-${UTIL_VERSION}.tgz`;
+const CORE_TGZ = `core-${CORE_VERSION}.tgz`;
+const CORE_MT_TGZ = `core-mt-${CORE_VERSION}.tgz`;
+
+const FFMPEG_TGZ_URL = `${NPM_URL}/@ffmpeg/ffmpeg/-/${FFMPEG_TGZ}`;
+const UTIL_TGZ_URL = `${NPM_URL}/@ffmpeg/util/-/${UTIL_TGZ}`;
+const CORE_TGZ_URL = `${NPM_URL}/@ffmpeg/core/-/${CORE_TGZ}`;
+const CORE_MT_TGZ_URL = `${NPM_URL}/@ffmpeg/core-mt/-/${CORE_MT_TGZ}`;
+
+const mkdir = (dir) => {
+  !fs.existsSync(dir) && fs.mkdirSync(dir);
+};
+
+const downloadAndUntar = async (url, tgzName, dst) => {
+  const dir = `${ROOT}/${dst}`;
+  if (fs.existsSync(dir)) {
+    console.log(`found @ffmpeg/${dst} assets.`);
+    return;
+  }
+  console.log(`download and untar ${url}`);
+  mkdir(dir);
+  const data = Buffer.from(await (await fetch(url)).arrayBuffer());
+  fs.writeFileSync(tgzName, data);
+
+  await tar.x({ file: tgzName, C: `${ROOT}/${dst}` });
+  fs.unlinkSync(tgzName);
+};
+
+mkdir(ROOT);
+downloadAndUntar(FFMPEG_TGZ_URL, FFMPEG_TGZ, "ffmpeg");
+downloadAndUntar(UTIL_TGZ_URL, UTIL_TGZ, "util");
+downloadAndUntar(CORE_TGZ_URL, CORE_TGZ, "core");
+downloadAndUntar(CORE_MT_TGZ_URL, CORE_MT_TGZ, "core-mt");