fix tomcat span without peer host and peer port issue

skywalking-sniffer/skywalking-sdk-plugin/dubbo-plugin/src/main/java/com/a/eye/skywalking/plugin/dubbo/DubboInterceptor.java

@@ -55,10 +55,10 @@ public class DubboInterceptor implements InstanceMethodsAroundInterceptor {
         Tags.URL.set(span, generateRequestURL(requestURL, invocation));
         Tags.COMPONENT.set(span, DUBBO_COMPONENT);
         Tags.SPAN_LAYER.asRPCFramework(span);
+        Tags.PEER_HOST.set(span, requestURL.getHost());
+        Tags.PEER_PORT.set(span, requestURL.getPort());
 
         if (isConsumer) {
-            Tags.PEER_HOST.set(span, requestURL.getHost());
-            Tags.PEER_PORT.set(span, requestURL.getPort());
             Tags.SPAN_KIND.set(span, Tags.SPAN_KIND_CLIENT);
             ContextCarrier contextCarrier = new ContextCarrier();
             ContextManager.INSTANCE.inject(contextCarrier);

skywalking-sniffer/skywalking-sdk-plugin/tomcat-7.x-8.x-plugin/src/main/java/com/a/eye/skywalking/plugin/tomcat78x/TomcatInterceptor.java

@@ -43,6 +43,8 @@ public class TomcatInterceptor implements InstanceMethodsAroundInterceptor {
 
         Span span = ContextManager.INSTANCE.createSpan(request.getRequestURI());
         Tags.COMPONENT.set(span, TOMCAT_COMPONENT);
+        Tags.PEER_HOST.set(span, fetchRequestPeerHost(request));
+        Tags.PEER_PORT.set(span, request.getRemotePort());
         Tags.SPAN_KIND.set(span, Tags.SPAN_KIND_SERVER);
         Tags.URL.set(span, request.getRequestURL().toString());
         Tags.SPAN_LAYER.asHttp(span);
@@ -76,4 +78,29 @@ public class TomcatInterceptor implements InstanceMethodsAroundInterceptor {
         Tags.ERROR.set(span, true);
     }
 
+    /**
+     *
+     * @param request
+     * @return
+     */
+    public String fetchRequestPeerHost(HttpServletRequest request) {
+        String ip = request.getHeader("X-Forwarded-For");
+        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
+            ip = request.getHeader("Proxy-Client-IP");
+        }
+        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
+            ip = request.getHeader("WL-Proxy-Client-IP");
+        }
+        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
+            ip = request.getHeader("HTTP_CLIENT_IP");
+        }
+        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
+            ip = request.getHeader("HTTP_X_FORWARDED_FOR");
+        }
+        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
+            ip = request.getRemoteAddr();
+        }
+        return ip;
+    }
+
 }