Add version to build and the archived asar app (#854)

scripts/build-version.js

@@ -0,0 +1,37 @@
+#!/usr/bin/env node
+
+const fs = require("fs");
+const path = require("path");
+const asar = require("asar");
+
+const zero = digit => `0${digit}`.slice(-2);
+
+const versionDate = date => {
+  const date_ = `${date.getFullYear()}-${zero(date.getMonth() + 1)}-${zero(
+    date.getDate(),
+  )}`;
+  const time = `${zero(date.getHours())}-${zero(date.getMinutes())}-${zero(
+    date.getSeconds(),
+  )}`;
+  return `${date_}-${time}`;
+};
+
+const now = new Date();
+
+const data = JSON.stringify(
+  {
+    app: `excalidraw-${versionDate(now)}.asar`,
+    version: versionDate(now),
+  },
+  undefined,
+  2,
+);
+
+fs.writeFileSync(path.join("build", "version.json"), data);
+
+(async () => {
+  const src = "build/";
+  const dest = path.join("build", `excalidraw-${versionDate(now)}.asar`);
+
+  await asar.createPackage(src, dest);
+})();