nginx-default.conf

# SPA: serve index.html for client-side routing; listen on 8080 for OpenShift
server {
    listen 8080;
    root /usr/share/nginx/html;
    index index.html;

    # Security headers
    add_header X-Frame-Options "DENY" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    location / {
        try_files $uri $uri/ /index.html;
    }

    # Reverse-proxy /api requests to the backend service.
    # __BACKEND_SERVICE_URL__ is replaced at container startup by docker-entrypoint.sh.
    # __RESOLVER__ is replaced with the nameserver from /etc/resolv.conf so that
    # nginx re-resolves the upstream hostname on each request rather than caching
    # the IP at startup (which causes 502s after the backend container is restarted).
    # All backend controllers use the /api/ prefix, so no path rewriting is needed.
    # Using a variable in proxy_pass disables URI prefix replacement in nginx, so
    # proxy_pass must point to just the upstream (no path suffix). nginx then passes
    # the full request URI unchanged — e.g. /api/auth/me → backend:/api/auth/me.
    location /api/ {
        resolver __RESOLVER__ valid=10s;
        set $upstream __BACKEND_SERVICE_URL__;
        client_max_body_size 100m;
        proxy_pass $upstream;
        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;

        # The auth callback sets multiple JWT cookies (access_token, refresh_token,
        # id_token, csrf_token) whose combined Set-Cookie headers exceed nginx's
        # default proxy buffer size, causing 502 Bad Gateway.
        proxy_buffer_size 16k;
        proxy_buffers 4 16k;
    }
}