elnudrop: nginx & proof of concept server outage handling

hosts/elnudrop/default.nix

@@ -1,5 +1,4 @@
 { lib, user, ... }:
-
 let keys = [
   "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEQNlGt62dBMojVCX7EUIia+wfSDfLzV4YCPi8SZ2xrp elnu@elnu.com"
 ]; in
@@ -9,6 +8,39 @@ let keys = [
     # Remember to update for new instances
     ./networking.nix # generated at runtime by nixos-infect
   ];
+  networking.firewall = {
+    enable = true;
+    allowedTCPPorts = [ 80 443 ];
+  };
+  security.acme = {
+    acceptTerms = true;
+    defaults.email = "elnu@elnu.com";
+  };
+  services.nginx = {
+    enable = true;
+    virtualHosts = {
+      "default" = {
+        default = true;
+        serverName = null;
+        # https://stackoverflow.com/a/42802777
+        locations."/".return = "444";
+      };
+      "jichan.org" = {
+        extraConfig = ''
+          error_page 502 /502.html;
+        '';
+        locations = {
+          "/" = {
+            proxyPass = "http://127.0.0.1:8000";
+            proxyWebsockets = true;
+          };
+          "/502.html".root = "${./hosts/jichan.org}";
+          "/logo.svg".root = "${./hosts/jichan.org}";
+          "/missing.min.css".root = "${./hosts/jichan.org}";
+        };
+      };
+    };
+  };
   services.do-agent.enable = true;
   services.openssh.enable = true;
   users.users.root.openssh.authorizedKeys.keys = keys;