常见处理器使用案例

解析 JSON 日志、标准化字段名称并添加环境信息：

processor:
  - parse_json: {}
  - rename_keys:
      entries:
        - from_key: "timestamp"
          to_key: "@timestamp"
        - from_key: "log_level"
          to_key: "level"
  - add_entries:
      entries:
        - key: "environment"
          value: "production"
        - key: "application"
          value: "payment-service"

对状态代码进行标准化处理并移除敏感数据：

processor:
  - uppercase_string:
      with_keys: ["status", "method"]
  - delete_entries:
      with_keys: ["credit_card", "password"]
  - substitute_string:
      entries:
        - source: "status"
          from: "SUCCESS"
          to: "OK"

提取用户信息和格式以进行分析：

processor:
  - extract_value:
      entries:
        - source: "user_agent"
          target: "browser"
          from: "(?<browser>Chrome|Firefox|Safari)"
          to: "${browser}"
  - lowercase_string:
      with_keys: ["browser"]
  - move_keys:
      entries:
        - from_key: "browser"
          to_key: "user_data.browser"

使用条目级 when 条件，根据日志严重性添加不同的元数据：

processor:
  - add_entries:
      entries:
        - key: "alert_level"
          value: "critical"
          when: "log.level == 'ERROR'"
        - key: "alert_level"
          value: "info"
          when_else: "log.level == 'ERROR'"

筛选掉来自第三方来源的调试和跟踪日志条目，以降低噪音和存储成本：

processor:
  - drop_events:
      when: "log.level in {'DEBUG', 'TRACE'}"
      handle_expression_failure: "skip"

仅在环境为生产环境时才删除敏感字段：

processor:
  - delete_entries:
      with_keys: ["password", "api_key", "ssn"]
      when: "environment in {'prod', 'staging'}"