Handle dynamic redirection.

index.md

@@ -5,9 +5,7 @@ nav_order: 1
 ---
 
 <!-- Auto redirect to the entry point of the mainsite -->
-<meta http-equiv="refresh" content="0; url=https://owasp.github.io/secure-headers-project/index/" />
 <meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate">
 <meta http-equiv="Pragma" content="no-cache">
 <meta http-equiv="Expires" content="0">
-<p>If you are not redirected automatically, <a href="https://owasp.github.io/secure-headers-project/index/">click here</a>.</p>
-<script> window.location.href = "https://owasp.github.io/secure-headers-project/index/"; </script>
+<script src="mainsite/assets/js/root-path-redirection-handler.js"></script>

mainsite/assets/js/root-path-redirection-handler.js

@@ -0,0 +1,20 @@
+/*
+Script to dynamically handle the redirection to the "/index" path depending on the initial domain requested:
+- The GitHub page
+- The custom sub domain
+*/
+const owaspSubDomain = "secure-headers-project.owasp.org";
+const githubPageSubDomain = "owasp.github.io";
+const sourceDomain = window.location.hostname;
+
+if (sourceDomain === owaspSubDomain) {
+    const targetLocation = `https://${owaspSubDomain}/index/`;
+    console.info(`Visitor come from the custom sub domain so redirect it to '${targetLocation}'...`);
+    window.location.replace(targetLocation);
+} else if (sourceDomain === githubPageSubDomain) {
+    const targetLocation = `https://${githubPageSubDomain}/secure-headers-project/index/`;
+    console.info(`Visitor come from the GH page domain so redirect it to '${targetLocation}'...`);
+    window.location.replace(targetLocation);
+} else {
+    console.error("The source domain is not an expected one so do nothing !");
+}