# nginx.conf - RAG服务反向代理配置

upstream rag_backend {
    # 负载均衡策略：least_conn（最少连接）
    least_conn;

    # 多个RAG服务实例（可选，用于高可用）
    server rag-service-1:5001 max_fails=3 fail_timeout=30s;
    # server rag-service-2:5001 max_fails=3 fail_timeout=30s;
    # server rag-service-3:5001 max_fails=3 fail_timeout=30s;
}

server {
    listen 80;
    server_name rag.example.com;

    # 请求体大小限制（文档上传）
    client_max_body_size 100M;

    # 超时配置（RAG问答可能较慢）
    proxy_connect_timeout 120s;
    proxy_send_timeout 120s;
    proxy_read_timeout 120s;

    # RAG服务代理
    location / {
        proxy_pass http://rag_backend;
        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;

        # SSE流式响应支持
        proxy_buffering off;
        proxy_cache off;
        proxy_http_version 1.1;
        chunked_transfer_encoding on;
    }

    # 健康检查
    location /health {
        proxy_pass http://rag_backend/health;
        access_log off;
    }

    # 请求限流（防止滥用）
    limit_req_zone $binary_remote_addr zone=rag_limit:10m rate=10r/s;
    limit_req zone=rag_limit burst=20 nodelay;
}

# HTTPS配置（推荐）
server {
    listen 443 ssl http2;
    server_name rag.example.com;

    ssl_certificate /etc/nginx/ssl/cert.pem;
    ssl_certificate_key /etc/nginx/ssl/key.pem;

    # 其他配置同上...
}