CertZipDL

src/server.js

@@ -133,6 +133,26 @@ function startRedirectServer() {
 
   http
     .createServer((req, res) => {
+      // A zip, because browsers block bare certificate downloads.
+      if (req.url === '/ca.zip') {
+        try {
+          const zip = tls.caBundleZip();
+          if (!zip) {
+            res.writeHead(404, { 'Content-Type': 'text/plain' });
+            return res.end('No certificate authority has been generated yet.');
+          }
+          res.writeHead(200, {
+            'Content-Type': 'application/zip',
+            'Content-Disposition': 'attachment; filename="visitor-signin-certificates.zip"',
+            'Content-Length': zip.length,
+          });
+          return res.end(zip);
+        } catch (err) {
+          res.writeHead(500, { 'Content-Type': 'text/plain' });
+          return res.end(`Could not build the bundle: ${err.message}`);
+        }
+      }
+
       // DER for Apple tooling, PEM for everything else.
       if (req.url === '/ca.cer' || req.url === '/ca.der') {
         try {