对请求的API调用过滤，记录接口的请求时间，方便日志审计、告警、分析等运维操作

pig-gateway/src/main/java/com/pig4cloud/pig/gateway/filter/ApiLoggingFilter.java

+package com.pig4cloud.pig.gateway.filter;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.cloud.gateway.filter.GatewayFilterChain;
+import org.springframework.cloud.gateway.filter.GlobalFilter;
+import org.springframework.core.Ordered;
+import org.springframework.stereotype.Component;
+import org.springframework.web.server.ServerWebExchange;
+import reactor.core.publisher.Mono;
+
+import java.util.List;
+
+/**
+ * @author zhangran
+ * @date 2021/7/13
+ * <p>
+ * 全局拦截器，作用所有的微服务
+ * <p>
+ * 1. 对请求的API调用过滤，记录接口的请求时间，方便日志审计、告警、分析等运维操作
+ * 2. 后期可以扩展对接其他日志系统
+ * <p>
+ */
+@Slf4j
+@Component
+public class ApiLoggingFilter implements GlobalFilter, Ordered {
+
+	private static final String START_TIME = "startTime";
+	private static final String X_REAL_IP = "X-Real-IP";//nginx需要配置
+
+	@Override
+	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
+		String info = String.format("Method:{%s} Host:{%s} Path:{%s} Query:{%s}",
+				exchange.getRequest().getMethod().name(),
+				exchange.getRequest().getURI().getHost(),
+				exchange.getRequest().getURI().getPath(),
+				exchange.getRequest().getQueryParams());
+		if (log.isDebugEnabled()) {
+			log.debug(info);
+		}
+		exchange.getAttributes().put(START_TIME, System.currentTimeMillis());
+		return chain.filter(exchange).then(Mono.fromRunnable(() -> {
+			Long startTime = exchange.getAttribute(START_TIME);
+			if (startTime != null) {
+				Long executeTime = (System.currentTimeMillis() - startTime);
+				List<String> ips = exchange.getRequest().getHeaders().get(X_REAL_IP);
+				String ip = ips != null ? ips.get(0) : null;
+				String api = exchange.getRequest().getURI().getRawPath();
+				int code = exchange.getResponse().getStatusCode() != null ? exchange.getResponse().getStatusCode().value() : 500;
+				//当前仅记录日志，后续可以添加日志队列，来过滤请求慢的接口
+				if (log.isDebugEnabled()) {
+					log.debug("来自IP地址：{}的请求接口：{}，响应状态码：{}，请求耗时：{}ms", ip, api, code, executeTime);
+				}
+			}
+		}));
+	}
+
+	@Override
+	public int getOrder() {
+		return Ordered.LOWEST_PRECEDENCE;
+	}
+
+}