From 4cd42b982496da30f78b1b434b366dba2ecaba31 Mon Sep 17 00:00:00 2001
From: Pim van Pelt <pim@ipng.ch>
Date: Thu, 26 Sep 2024 14:37:52 +0200
Subject: [PATCH] Make the ntags cycle every week

---
 static/app/go/index.html | 51 +++++++++++++++++++++-------------------
 1 file changed, 27 insertions(+), 24 deletions(-)

diff --git a/static/app/go/index.html b/static/app/go/index.html
index e584d27..f8ecae8 100644
--- a/static/app/go/index.html
+++ b/static/app/go/index.html
@@ -6,30 +6,33 @@
   <meta charset="utf-8">
   <script type="text/JavaScript">
 
-var redir_url = "https://ipng.ch/";
-const urls = {
-  "ntag00": "/s/articles/2021/09/21/vpp-linux-cp-part7/",
-  "ntag01": "/s/articles/2021/12/23/vpp-linux-cp-virtual-machine-playground/",
-  "ntag02": "/s/articles/2022/01/12/case-study-virtual-leased-line-vll-in-vpp/",
-  "ntag03": "/s/articles/2022/02/14/case-study-vlan-gymnastics-with-vpp/",
-  "ntag04": "/s/articles/2022/03/27/vpp-configuration-part1/",
-  "ntag05": "/s/articles/2022/10/14/vpp-lab-setup/",
-  "ntag06": "/s/articles/2023/03/11/case-study-centec-mpls-core/",
-  "ntag07": "/s/articles/2023/04/09/vpp-monitoring/",
-  "ntag08": "/s/articles/2023/05/28/vpp-mpls-part-4/",
-  "ntag09": "/s/articles/2023/11/11/debian-on-mellanox-sn2700-32x100g/",
-  "ntag10": "/s/articles/2023/12/17/debian-on-ipngs-vpp-routers/",
-  "ntag11": "/s/articles/2024/01/27/vpp-python-api/",
-  "ntag12": "/s/articles/2024/02/10/vpp-on-freebsd-part-1/",
-  "ntag13": "/s/articles/2024/03/06/vpp-with-babel-part-1/",
-  "ntag14": "/s/articles/2024/04/06/vpp-with-loopback-only-ospfv3-part-1/",
-  "ntag15": "/s/articles/2024/04/27/freeix-remote/",
-  "END": "/"
-};
+const ntag_list = [
+  "/s/articles/2021/09/21/vpp-linux-cp-part7/",
+  "/s/articles/2021/12/23/vpp-linux-cp-virtual-machine-playground/",
+  "/s/articles/2022/01/12/case-study-virtual-leased-line-vll-in-vpp/",
+  "/s/articles/2022/02/14/case-study-vlan-gymnastics-with-vpp/",
+  "/s/articles/2022/03/27/vpp-configuration-part1/",
+  "/s/articles/2022/10/14/vpp-lab-setup/",
+  "/s/articles/2023/03/11/case-study-centec-mpls-core/",
+  "/s/articles/2023/04/09/vpp-monitoring/",
+  "/s/articles/2023/05/28/vpp-mpls-part-4/",
+  "/s/articles/2023/11/11/debian-on-mellanox-sn2700-32x100g/",
+  "/s/articles/2023/12/17/debian-on-ipngs-vpp-routers/",
+  "/s/articles/2024/01/27/vpp-python-api/",
+  "/s/articles/2024/02/10/vpp-on-freebsd-part-1/",
+  "/s/articles/2024/03/06/vpp-with-babel-part-1/",
+  "/s/articles/2024/04/06/vpp-with-loopback-only-ospfv3-part-1/",
+  "/s/articles/2024/04/27/freeix-remote/"
+];
 
-let key = window.location.hash.slice(1);
-if (key in urls) {
-  redir_url = urls[key];
+var redir_url = "https://ipng.ch/";
+var key = window.location.hash.slice(1);
+if (key.startsWith("ntag")) {
+  let week = Math.round(new Date().getTime() / 1000 / (7*24*3400));
+  let num = parseInt(key.slice(-2));
+  let idx = (num + week) % ntag_list.length;
+  console.log("(ntag " + num + " + week number " + week + ") % " + ntag_list.length + " = " + idx);
+  redir_url = ntag_list[idx];
 }
 
 console.log("Redirecting to " + redir_url + " - off you go!");
@@ -40,7 +43,7 @@ window.location = redir_url;
 
 <pre>
 Usage: https://ipng.ch/app/go/#&lt;key&gt;
-Example: <a href="/app/go/#END">#END</a>
+Example: <a href="/app/go/#ntag00">#ntag00</a>
 
 Also, this page requires javascript.