# 在 http 塊中定義映射規(guī)則
map $request_uri $loggable {
    default 1;                    # 默認記錄
    ~*^/health$ 0;                # 健康檢查不記錄
    ~*^/ready$ 0;                 # 就緒檢查不記錄
    ~*^/live$ 0;                  # 活躍檢查不記錄
    ~*^/metrics$ 0;               # Prometheus 指標不記錄
    ~*^/swagger-ui.html$ 0;       # Swagger UI 不記錄
    ~*^/v1/health$ 0;             # 微服務健康端點
}
# 在 server 塊中應用條件日志
server {
    listen 80;
    server_name example.com;
    # 關鍵：只有 $loggable 為 1 時才寫入 access log
    access_log /var/log/nginx/access.log combined if=$loggable;
    # 其他配置...
    location / {
        proxy_pass http://backend;
    }
    location /health {
        return 200 "OK";
    }
    location /metrics {
        stub_status on;
        access_log off;  # 也可單獨關閉
    }
}

map $http_user_agent $log_user_agent {
    default 1;
    ~*Googlebot 0;
    ~*Baiduspider 0;
    ~*YandexBot 0;
    ~*SemrushBot 0;
    ~*AhrefsBot 0;
    ~*MJ12bot 0;
    ~*DotBot 0;
    ~*ZoominfoBot 0;
}
# 組合多個條件：必須同時滿足 loggable=1 且 log_user_agent=1 才記錄
map $loggable$log_user_agent $final_log {
    default 0;
    "11" 1;
}
server {
    access_log /var/log/nginx/access.log combined if=$final_log;
}

# 為 API 網(wǎng)關單獨記錄
server {
    listen 8080;
    server_name api.example.com;
    access_log /var/log/nginx/api-access.log combined if=$loggable;
    error_log /var/log/nginx/api-error.log warn;
    location / {
        proxy_pass http://api-service;
    }
}
# 為靜態(tài)資源服務器關閉 access log
server {
    listen 8081;
    server_name static.example.com;
    access_log off;  # 完全關閉
    error_log /var/log/nginx/static-error.log error;
    location / {
        root /var/www/static;
        expires 1y;
    }
}

# 全局 error_log 配置（建議放在 nginx.conf 最上方）
error_log /var/log/nginx/error.log warn;
# 如果需要更細粒度控制，可為不同 server 設置不同級別
server {
    listen 80;
    server_name example.com;
    error_log /var/log/nginx/example-error.log warn;
    # 某個敏感服務，記錄更詳細（僅臨時）
    # error_log /var/log/nginx/sensitive-error.log notice; # 臨時調試用
}

// HealthCheckController.java
package com.example.controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HealthCheckController {
    @GetMapping("/health")
    public String health() {
        return "UP";
    }
    @GetMapping("/ready")
    public String ready() {
        // 檢查數(shù)據(jù)庫、緩存、消息隊列等依賴
        return "READY";
    }
    @GetMapping("/live")
    public String live() {
        // 僅檢查進程是否存活
        return "LIVE";
    }
    @GetMapping("/metrics")
    public String metrics() {
        // 返回 Prometheus 格式指標
        return """
            # HELP http_requests_total Total number of HTTP requests
            # TYPE http_requests_total counter
            http_requests_total{method="GET",status="200"} 12345
            """;
    }
}

# nginx.conf - 全局配置
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log warn;  # ? 生產(chǎn)推薦級別
pid /run/nginx.pid;
events {
    worker_connections 1024;
}
http {
    # 定義是否記錄日志的映射規(guī)則
    map $request_uri $loggable {
        default 1;
        ~*^/health$ 0;
        ~*^/ready$ 0;
        ~*^/live$ 0;
        ~*^/metrics$ 0;
        ~*^/swagger-ui.html$ 0;
        ~*^/v1/health$ 0;
    }
    # 定義是否記錄爬蟲
    map $http_user_agent $log_user_agent {
        default 1;
        ~*Googlebot 0;
        ~*Baiduspider 0;
        ~*YandexBot 0;
        ~*SemrushBot 0;
        ~*AhrefsBot 0;
        ~*MJ12bot 0;
        ~*DotBot 0;
        ~*ZoominfoBot 0;
    }
    # 組合條件：只有非健康且非爬蟲才記錄
    map $loggable$log_user_agent $final_log {
        default 0;
        "11" 1;
    }
    # 定義自定義日志格式（僅記錄關鍵字段）
    log_format custom '$remote_addr - $remote_user [$time_local] '
                      '"$request" $status $body_bytes_sent '
                      '"$http_referer" "$http_user_agent" '
                      '$upstream_response_time $request_time';
    access_log /var/log/nginx/access.log custom if=$final_log;
    # 開啟壓縮，減少網(wǎng)絡傳輸（間接降低日志體積）
    gzip on;
    gzip_types text/plain application/json application/javascript text/css;
    include /etc/nginx/conf.d/*.conf;
}

# /etc/nginx/conf.d/app.conf
server {
    listen 80;
    server_name api.example.com;
    # 關閉靜態(tài)資源日志
    location ~* \.(jpg|jpeg|png|gif|ico|css|js|woff2)$ {
        root /var/www/static;
        expires 1y;
        access_log off;  # ? 關閉
    }
    # 代理到 Java 應用
    location / {
        proxy_pass http://127.0.0.1:8080;
        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;
        # 優(yōu)化：關閉不必要的代理日志
        proxy_cache off;
        proxy_buffering off;
    }
    # 明確關閉這些路徑的訪問日志
    location /health {
        return 200 "UP";
        access_log off;
    }
    location /ready {
        return 200 "READY";
        access_log off;
    }
    location /live {
        return 200 "LIVE";
        access_log off;
    }
    location /metrics {
        stub_status on;
        access_log off;
    }
}

# 精簡版：只記錄核心指標
log_format concise '$remote_addr - $remote_user [$time_local] '
                   '"$request_method $request_uri $server_protocol" '
                   '$status $body_bytes_sent '
                   '$request_time $upstream_response_time';
access_log /var/log/nginx/access.log concise if=$final_log;

access_log /var/log/nginx/access.log concise buffer=32k flush=5s if=$final_log;

# /etc/logrotate.d/nginx
/var/log/nginx/*.log {
    daily
    missingok
    rotate 14
    compress
    delaycompress
    notifempty
    create 0640 nginx adm
    sharedscripts
    postrotate
        [ -f /var/run/nginx.pid ] && kill -USR1 `cat /var/run/nginx.pid`
    endscript
}

sudo logrotate -d /etc/logrotate.d/nginx  # 模擬運行
sudo logrotate -f /etc/logrotate.d/nginx  # 強制執(zhí)行

{
  "title": "Nginx 日志調優(yōu)監(jiān)控",
  "panels": [
    {
      "title": "每日訪問日志體積",
      "type": "graph",
      "query": "sum(increase(nginx_access_log_bytes_total[1d]))",
      "alert": "如果 > 50GB，觸發(fā)磁盤告警"
    },
    {
      "title": "錯誤日志條目數(shù)（每分鐘）",
      "type": "stat",
      "query": "sum(rate(nginx_error_log_lines[1m]))",
      "alert": "如果 > 100/min，檢查后端服務"
    },
    {
      "title": "日志過濾率",
      "type": "gauge",
      "query": "1 - (sum(nginx_access_log_records_filtered) / sum(nginx_access_log_records_total))",
      "alert": "過濾率 < 70%，說明配置失效"
    }
  ]
}