gogs: add error pages

configs/workhorse/gogs.nix

@@ -1,10 +1,42 @@
-{ config, lib, ... }: {
+{ config, lib, pkgs, ... }:
+let
+
+  errorPages = pkgs.fetchgit {
+    url = "https://git.ingolf-wagner.de/palo/http-errors.git";
+    rev = "74b8e4c1d9bbba3db6ad858b888e1867318af1f0";
+    sha256 = "0czdzafx4k76q773lyf3vsjm74g1995iz542dhw15kpy5xbivsrg";
+  };
+
+  error = {
+    extraConfig = ''
+      error_page 400 /errors/400.html;
+      error_page 401 /errors/401.html;
+      error_page 402 /errors/402.html;
+      error_page 403 /errors/403.html;
+      error_page 404 /errors/404.html;
+      error_page 405 /errors/405.html;
+      error_page 406 /errors/406.html;
+      error_page 500 /errors/500.html;
+      error_page 501 /errors/501.html;
+      error_page 502 /errors/502.html;
+      error_page 503 /errors/503.html;
+      error_page 504 /errors/504.html;
+    '';
+    locations."^~ /errors/" = {
+      extraConfig = "internal;";
+      root = "${errorPages}/";
+    };
+  };
+
+in
+{
 
   services.nginx = {
     enable = true;
     statusPage = true;
     virtualHosts = {
       "git.${config.networking.hostName}.private" = {
+        extraConfig = error.extraConfig;
         locations."/" = {
           proxyPass = "http://${config.networking.hostName}.private:${
               toString config.services.gogs.httpPort
@@ -44,7 +76,6 @@
   };
   backup.all.restic.dirs = [ config.services.gogs.repositoryRoot ];
 
-
   #services.gitea = {
   #  enable = true;
   #  appName = "Git";