From 8801903d01e0f0464b8202516b5d8d038183c88d Mon Sep 17 00:00:00 2001
From: Dmitry Verkhoturov <paskal.07@gmail.com>
Date: Tue, 18 Aug 2026 21:55:44 +0100
Subject: [PATCH] Derive host from the page URL on self-served pages

Previously the pages Remark42 serves from /web/ carried a build-time host.
The `{% REMARK_URL %}` placeholder is substituted during the image and
release-asset builds, both of which write `http://127.0.0.1:8080`. Docker
rewrites it again at container start from REMARK_URL, but a release binary
has no equivalent step, so it serves demo, counter, last-comments and
deleteme pages pointing at the visitor's own loopback address. `counter.ejs`
additionally had that address hardcoded in two "note" links, which no
substitution touched.

These pages are served by Remark42 itself, so the host is whatever origin and
path prefix delivered them. Deriving it from `location` is correct at the root
and under a path prefix alike, and needs no build-time value. Sibling links
are now relative for the same reason.

`site_id` is left as a literal so the startup substitution in docker-init.sh
keeps matching it.

Reported by @andreas-hempel.

Resolves #1996.
---
 frontend/apps/remark42/templates/counter.ejs       |  6 +++---
 frontend/apps/remark42/templates/deleteme.ejs      |  2 +-
 frontend/apps/remark42/templates/demo.ejs          | 14 ++++++++++----
 frontend/apps/remark42/templates/last-comments.ejs |  2 +-
 4 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/frontend/apps/remark42/templates/counter.ejs b/frontend/apps/remark42/templates/counter.ejs
index b0999d47..b3c8f829 100644
--- a/frontend/apps/remark42/templates/counter.ejs
+++ b/frontend/apps/remark42/templates/counter.ejs
@@ -21,13 +21,13 @@
       <p>
         First counter with url from data-attribute:
         <span class="remark42__counter" data-url="https://remark42.com/demo/"></span>
-        (<a href="http://127.0.0.1:8080/web/" target="_blank">note</a>)
+        (<a href="./" target="_blank">note</a>)
       </p>
 
       <p>
         Second counter with url from global remark config:
         <span class="remark42__counter"></span>
-        (<a href="http://127.0.0.1:8080/web/" target="_blank">note</a>)
+        (<a href="./" target="_blank">note</a>)
       </p>
 
       <p>If it can't get url from data-attribute or remark config, it will try to use window.location.href for it.</p>
@@ -36,7 +36,7 @@
     <script>
       var remark_config = {
         site_id: 'remark',
-        host: '<%= htmlWebpackPlugin.options.REMARK_URL %>',
+        host: location.origin + location.pathname.replace(/\/[^/]*$/, '').replace(/\/web$/, ''),
         url: 'https://remark42.com/demo/',
         components: ['counter'],
       };
diff --git a/frontend/apps/remark42/templates/deleteme.ejs b/frontend/apps/remark42/templates/deleteme.ejs
index e51f9b47..397d4585 100644
--- a/frontend/apps/remark42/templates/deleteme.ejs
+++ b/frontend/apps/remark42/templates/deleteme.ejs
@@ -69,7 +69,7 @@
       <div class="preloader preloader_view_iframe"></div>
     </div>
     <script>
-      var remark_config = { host: '<%= htmlWebpackPlugin.options.REMARK_URL %>' };
+      var remark_config = { host: location.origin + location.pathname.replace(/\/[^/]*$/, '').replace(/\/web$/, '') };
     </script>
     <script src="deleteme.js"></script>
   </body>
diff --git a/frontend/apps/remark42/templates/demo.ejs b/frontend/apps/remark42/templates/demo.ejs
index 2c04a4ad..59dc468f 100644
--- a/frontend/apps/remark42/templates/demo.ejs
+++ b/frontend/apps/remark42/templates/demo.ejs
@@ -72,11 +72,11 @@
       </p>
       <div class="widgets">
         <div class="widget widgets__widget widgets__comments-widget">
-          <a class="widget__link" href="<%= htmlWebpackPlugin.options.REMARK_URL %>/web/last-comments.html">Last comments widget page</a><br />
-          <iframe class="widget__frame widget__comments-frame" src="<%= htmlWebpackPlugin.options.REMARK_URL %>/web/last-comments.html"></iframe>
+          <a class="widget__link widget__link_page_last-comments" href="./last-comments.html">Last comments widget page</a><br />
+          <iframe class="widget__frame widget__comments-frame"></iframe>
         </div>
         <div class="widget widgets__widget widgets__counter-widget">
-          <a class="widget__link" href="<%= htmlWebpackPlugin.options.REMARK_URL %>/web/counter.html">Counter widget page</a><br />
+          <a class="widget__link widget__link_page_counter" href="./counter.html">Counter widget page</a><br />
           <div class="widget__frame widget__counter-frame">Comments count: <span class="remark42__counter"></span></div>
         </div>
       </div>
@@ -121,9 +121,15 @@
         window.REMARK42.changeTheme('dark');
       });
 
+      var remarkBase = location.origin + location.pathname.replace(/\/[^/]*$/, '').replace(/\/web$/, '');
+
+      document.querySelector('.widget__link_page_last-comments').href = remarkBase + '/web/last-comments.html';
+      document.querySelector('.widget__comments-frame').src = remarkBase + '/web/last-comments.html';
+      document.querySelector('.widget__link_page_counter').href = remarkBase + '/web/counter.html';
+
       var remark_config = {
         site_id: 'remark',
-        host: '<%= htmlWebpackPlugin.options.REMARK_URL %>',
+        host: remarkBase,
         url: window.location.href,
         components: ['embed', 'counter'],
         // __colors__: {
diff --git a/frontend/apps/remark42/templates/last-comments.ejs b/frontend/apps/remark42/templates/last-comments.ejs
index 77240412..3bb1654d 100644
--- a/frontend/apps/remark42/templates/last-comments.ejs
+++ b/frontend/apps/remark42/templates/last-comments.ejs
@@ -26,7 +26,7 @@
     <script>
       var remark_config = {
         site_id: 'remark',
-        host: '<%= htmlWebpackPlugin.options.REMARK_URL %>',
+        host: location.origin + location.pathname.replace(/\/[^/]*$/, '').replace(/\/web$/, ''),
         components: ['last-comments'],
       };