WIP: generate SPA checksum to validate web page

apps/web/scripts/generateChecksums.js

@@ -0,0 +1,35 @@
+const fs = require("fs");
+const path = require("path");
+const crypto = require("crypto");
+
+// Path to the built index.html file. The expectation is that this file contains <script> tags to generate checksums for.
+const indexFile = process.argv.slice(2);
+const indexFileDir = path.dirname(indexFile[0]);
+
+// Read the index.html file.
+const index = fs.readFileSync(indexFile[0], "utf8");
+
+// Extract all the script tags.
+// captures the src tag in the `src` group and any inline script in the `inline` group.
+const scripts = index.matchAll(
+  /<script[^>]*?(?:src=(["\'])(?<src>(?:[\s\S](?!\1|>))*[\s\S]?)\1)?>(?<inline>[\s\S]*?)<\/script>/gm,
+);
+
+const checksums = {
+  inline: [],
+};
+
+for (const match of scripts) {
+  const src = match.groups.src;
+  const inline = match.groups.inline;
+  if (src) {
+    const file = src;
+    const fileContent = fs.readFileSync(path.join(indexFileDir, file), "utf8");
+    checksums[file] = crypto.createHash("sha256").update(fileContent).digest("hex");
+  }
+  if (inline) {
+    checksums.inline.push(crypto.createHash("sha256").update(inline).digest("hex"));
+  }
+}
+
+console.log(JSON.stringify(checksums, null, 2));