🚨 현상

• IP 주소로는 Swagger 접근이 되나, HTTPS 도메인으로는 UI가 깨지거나 설정 로드 실패 메시지 출력.

🔍 원인 분석

• 원인: Nginx가 /api/ 경로는 백엔드로 보내주지만, Swagger가 내부적으로 호출하는 API 명세 경로인 /api-docs를 모르고 있었음.

💡 해결 방법

• Nginx: location 블록에 api-docs, swagger-ui, v3/api-docs 경로를 백엔드(8080)로 프록시되도록 명시적으로 추가.

/etc/nginx/sites-available/rarego

server {
    server_name rarego.duckdns.org;

    # Backend API (Spring Boot)
    location /api/ {
        proxy_pass <http://localhost:8080>;
        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;
    }

    # API 및 OAuth2 관련 모든 경로를 백엔드로 전달
    location ~ ^/(api|oauth2|login/oauth2|api-docs|swagger-ui|v3/api-docs) {
        proxy_pass <http://localhost:8080>;
        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;
    }

    # Frontend (Next.js)
    location / {
        proxy_pass <http://localhost:3000>;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
    }

    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/rarego.duckdns.org/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/rarego.duckdns.org/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}
server {
    if ($host = rarego.duckdns.org) {
        return 301 https://$host$request_uri;
    } # managed by Certbot
    

    listen 80;
    server_name rarego.duckdns.org;
    return 404; # managed by Certbot

}