discourse: Don't patch the public path

Instead of patching the path to /public in Discourse's sources, make
the nginx configuration refer to the symlink in the discourse
package which points to the real path.

When there is a mismatch between the path nginx serves and the path
Discourse thinks it serves, we can run into issues like files not
being served - at least when sendfile requests from the ruby app are
processed by nginx. The issue I ran into most recently is that backup
downloads don't work.

Since Discourse refers to the public directory relative to the Rails
root in many places, it's much easier to just sync this path to the
nginx configuration than trying to patch all occurrences in the
sources. This should hopefully mean less potential for breakage in
future Discourse releases, too.

1 files changed, 4 insertions, 4 deletions

diff --git a/nixos/modules/services/web-apps/discourse.nix b/nixos/modules/services/web-apps/discourse.nix
index 1c7ffd59a59..18b61200aa1 100644
--- a/nixos/modules/services/web-apps/discourse.nix
+++ b/nixos/modules/services/web-apps/discourse.nix
@@ -841,7 +841,7 @@ in
         inherit (cfg) sslCertificate sslCertificateKey enableACME;
         forceSSL = lib.mkDefault tlsEnabled;
 
-        root = "/run/discourse/public";
+        root = "${cfg.package}/share/discourse/public";
 
         locations =
           let
@@ -893,7 +893,7 @@ in
               "~ ^/uploads/" = proxy {
                 extraConfig = cache_1y + ''
                   proxy_set_header X-Sendfile-Type X-Accel-Redirect;
-                  proxy_set_header X-Accel-Mapping /run/discourse/public/=/downloads/;
+                  proxy_set_header X-Accel-Mapping ${cfg.package}/share/discourse/public/=/downloads/;
 
                   # custom CSS
                   location ~ /stylesheet-cache/ {
@@ -915,7 +915,7 @@ in
               "~ ^/admin/backups/" = proxy {
                 extraConfig = ''
                   proxy_set_header X-Sendfile-Type X-Accel-Redirect;
-                  proxy_set_header X-Accel-Mapping /run/discourse/public/=/downloads/;
+                  proxy_set_header X-Accel-Mapping ${cfg.package}/share/discourse/public/=/downloads/;
                 '';
               };
               "~ ^/(svg-sprite/|letter_avatar/|letter_avatar_proxy/|user_avatar|highlight-js|stylesheets|theme-javascripts|favicon/proxied|service-worker)" = proxy {
@@ -942,7 +942,7 @@ in
               };
               "/downloads/".extraConfig = ''
                 internal;
-                alias /run/discourse/public/;
+                alias ${cfg.package}/share/discourse/public/;
               '';
             };
       };