From abd7e71f7120f69b2019ded10ecc586ff0f0b410 Mon Sep 17 00:00:00 2001
From: Phil Winder <phil@winderresearch.com>
Date: Wed, 15 Mar 2017 13:25:41 +0000
Subject: [PATCH] Match request to prevent metric for each ID.

---
 .../middleware/HTTPMonitoringInterceptor.java | 27 ++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/main/java/works/weave/socks/cart/middleware/HTTPMonitoringInterceptor.java b/src/main/java/works/weave/socks/cart/middleware/HTTPMonitoringInterceptor.java
index 36c68da44..963965799 100644
--- a/src/main/java/works/weave/socks/cart/middleware/HTTPMonitoringInterceptor.java
+++ b/src/main/java/works/weave/socks/cart/middleware/HTTPMonitoringInterceptor.java
@@ -1,12 +1,17 @@
 package works.weave.socks.cart.middleware;
 
 import io.prometheus.client.Histogram;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.web.method.HandlerMethod;
 import org.springframework.web.servlet.HandlerInterceptor;
 import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
+import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+import java.util.Map;
 
 public class HTTPMonitoringInterceptor implements HandlerInterceptor {
     static final Histogram requestLatency = Histogram.build()
@@ -20,6 +25,9 @@ public class HTTPMonitoringInterceptor implements HandlerInterceptor {
     @Value("${spring.application.name:carts}")
     private String serviceName;
 
+    @Autowired
+    private RequestMappingHandlerMapping requestMappingHandlerMapping;
+
     @Override
     public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse
             httpServletResponse, Object o) throws Exception {
@@ -36,7 +44,7 @@ public void postHandle(HttpServletRequest httpServletRequest, HttpServletRespons
         requestLatency.labels(
                 serviceName,
                 httpServletRequest.getMethod(),
-                httpServletRequest.getServletPath(),
+                getMatchingURLPattern(httpServletRequest),
                 Integer.toString(httpServletResponse.getStatus())
         ).observe(seconds);
     }
@@ -45,4 +53,21 @@ public void postHandle(HttpServletRequest httpServletRequest, HttpServletRespons
     public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse
             httpServletResponse, Object o, Exception e) throws Exception {
     }
+
+    private String getMatchingURLPattern(HttpServletRequest httpServletRequest) {
+        String res = httpServletRequest.getServletPath();
+
+        for (Map.Entry<RequestMappingInfo, HandlerMethod> item : requestMappingHandlerMapping
+                .getHandlerMethods().entrySet()) {
+            RequestMappingInfo mapping = item.getKey();
+            if (mapping.getPatternsCondition().getMatchingCondition(httpServletRequest) != null &&
+                    mapping.getMethodsCondition().getMatchingCondition(httpServletRequest) !=
+                            null) {
+                res = mapping.getPatternsCondition().getMatchingCondition(httpServletRequest)
+                        .getPatterns().iterator().next();
+                break;
+            }
+        }
+        return res;
+    }
 }