start project

frontend/nginx.conf

@@ -4,7 +4,21 @@
 # Putting both behind one origin means the browser never issues a cross-origin
 # request, so no CORS pre-flight, no third-party cookie rules, and the API can
 # keep its allow-list empty in production.
+#
+# Every location includes security-headers.conf rather than relying on a
+# server-level declaration - see the comment in that file for why inheritance
+# cannot be trusted here.  Proxied locations additionally include
+# proxy-backend.conf, which forwards the client details and drops the
+# duplicate security headers Django emits.
 # -----------------------------------------------------------------------------
+
+# The SPA's policy: no inline script, nothing loaded off-origin.  The bundle is
+# fully self-hosted, so this can stay strict.  ('unsafe-inline' for styles is
+# still required by the inline style attributes React emits.)
+map $host $spa_csp {
+    default "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'; font-src 'self'; frame-ancestors 'none'; base-uri 'self'; form-action 'self'";
+}
+
 server {
     listen 8080;
     server_name _;
@@ -12,14 +26,6 @@ server {
     root /usr/share/nginx/html;
     index index.html;
 
-    # --- Security headers ----------------------------------------------------
-    add_header X-Content-Type-Options "nosniff" always;
-    add_header X-Frame-Options "DENY" always;
-    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
-    add_header Permissions-Policy "camera=(), microphone=(), geolocation=(), interest-cohort=()" always;
-    # The bundle is fully self-hosted, so the policy can stay strict.
-    add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'; font-src 'self'; frame-ancestors 'none'; base-uri 'self'; form-action 'self'" always;
-
     server_tokens off;
     client_max_body_size 2m;
 
@@ -29,40 +35,59 @@ server {
 
     location = /healthz {
         access_log off;
+        include /etc/nginx/conf.d/security-headers.conf;
         add_header Content-Type text/plain;
         return 200 'ok';
     }
 
     # Hashed assets never change under the same name - cache them hard.
     location /assets/ {
+        include /etc/nginx/conf.d/security-headers.conf;
+        add_header Content-Security-Policy $spa_csp always;
         expires 1y;
         add_header Cache-Control "public, immutable";
         try_files $uri =404;
     }
 
-    location /api/ {
+    # --- API documentation ---------------------------------------------------
+    # Swagger UI and ReDoc bootstrap themselves from an inline <script> block
+    # that drf-spectacular generates, which the SPA's "script-src 'self'"
+    # blocks - the page loads but renders blank.  Rather than punching
+    # 'unsafe-inline' into the policy the SPA runs under, the exemption is
+    # confined to these three documentation paths: they render no user data and
+    # no user input, they load nothing off-origin (drf-spectacular-sidecar
+    # serves the bundles from /static/, not a CDN), and in production they are
+    # not routed at all - SERVE_API_DOCS defaults to false there.
+    location ~ ^/api/(docs|redoc|schema)/ {
+        include /etc/nginx/conf.d/security-headers.conf;
+        add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'; font-src 'self'; frame-ancestors 'none'; base-uri 'self'; form-action 'self'" always;
+
+        include /etc/nginx/conf.d/proxy-backend.conf;
         proxy_pass http://backend:8000;
-        proxy_http_version 1.1;
-        proxy_set_header Host $host;
-        proxy_set_header X-Real-IP $remote_addr;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
-        proxy_set_header X-Request-ID $request_id;
-        proxy_connect_timeout 5s;
-        proxy_read_timeout 30s;
     }
 
-    # Django admin and API documentation share the backend origin.
-    location ~ ^/(admin|static)/ {
+    location /api/ {
+        include /etc/nginx/conf.d/security-headers.conf;
+        add_header Content-Security-Policy $spa_csp always;
+
+        include /etc/nginx/conf.d/proxy-backend.conf;
+        proxy_pass http://backend:8000;
+    }
+
+    # Django admin and static files share the backend origin.
+    location ~ ^/(admin|static)/ {
+        include /etc/nginx/conf.d/security-headers.conf;
+        add_header Content-Security-Policy $spa_csp always;
+
+        include /etc/nginx/conf.d/proxy-backend.conf;
         proxy_pass http://backend:8000;
-        proxy_set_header Host $host;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
     }
 
     # Client-side routing: unknown paths fall back to the SPA shell.
     location / {
-        try_files $uri $uri/ /index.html;
+        include /etc/nginx/conf.d/security-headers.conf;
+        add_header Content-Security-Policy $spa_csp always;
         add_header Cache-Control "no-cache";
+        try_files $uri $uri/ /index.html;
     }
 }