fix(nginx): add Cache-Control no-cache for HTML responses to prevent stale SPA shell after deploy

Author: thejoeejoee

conf/prace.spseol.cz.conf

@@ -1,3 +1,9 @@
+# no-cache only for HTML responses, leave static assets untouched
+map $upstream_http_content_type $html_cache_control {
+    ~text/html "no-cache";
+    default    "";
+}
+
 server {
     server_name _;
 
@@ -55,6 +61,7 @@ server {
     add_header X-Content-Type-Options "nosniff";
     add_header X-Frame-Options "SAMEORIGIN";
     add_header X-XSS-Protection "1; mode=block";
+    add_header Cache-Control $html_cache_control;
 
     ssl_certificate /etc/letsencrypt/live/prace.spseol.cz/fullchain.pem;
     ssl_certificate_key /etc/letsencrypt/live/prace.spseol.cz/privkey.pem;