From 1a6204929ee80cb9396fe70410f1e932763493d1 Mon Sep 17 00:00:00 2001
From: Phil Winder <phil@winderresearch.com>
Date: Thu, 16 Mar 2017 12:37:02 +0000
Subject: [PATCH] Obtain url matchers for both spring and spring-boot
 endpoints.

---
 .../middleware/HTTPMonitoringInterceptor.java | 72 +++++++++++++------
 1 file changed, 49 insertions(+), 23 deletions(-)

diff --git a/src/main/java/works/weave/socks/orders/middleware/HTTPMonitoringInterceptor.java b/src/main/java/works/weave/socks/orders/middleware/HTTPMonitoringInterceptor.java
index 6d1f6a0..802a0d3 100644
--- a/src/main/java/works/weave/socks/orders/middleware/HTTPMonitoringInterceptor.java
+++ b/src/main/java/works/weave/socks/orders/middleware/HTTPMonitoringInterceptor.java
@@ -3,15 +3,20 @@
 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.context.ApplicationContext;
+import org.springframework.data.rest.core.config.RepositoryRestConfiguration;
+import org.springframework.data.rest.core.mapping.ResourceMappings;
+import org.springframework.data.rest.webmvc.RepositoryRestHandlerMapping;
+import org.springframework.data.rest.webmvc.support.JpaHelper;
 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.condition.PatternsRequestCondition;
 import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import java.util.Map;
+import java.util.HashSet;
+import java.util.Set;
 
 public class HTTPMonitoringInterceptor implements HandlerInterceptor {
     static final Histogram requestLatency = Histogram.build()
@@ -21,13 +26,20 @@ public class HTTPMonitoringInterceptor implements HandlerInterceptor {
             .register();
 
     private static final String startTimeKey = "startTime";
-
+    @Autowired
+    ResourceMappings mappings;
+    @Autowired
+    JpaHelper jpaHelper;
+    @Autowired
+    RepositoryRestConfiguration repositoryConfiguration;
+    @Autowired
+    ApplicationContext applicationContext;
+    @Autowired
+    RequestMappingHandlerMapping requestMappingHandlerMapping;
+    private Set<PatternsRequestCondition> urlPatterns;
     @Value("${spring.application.name:orders}")
     private String serviceName;
 
-    @Autowired
-    private RequestMappingHandlerMapping requestMappingHandlerMapping;
-
     @Override
     public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse
             httpServletResponse, Object o) throws Exception {
@@ -41,12 +53,15 @@ public void postHandle(HttpServletRequest httpServletRequest, HttpServletRespons
         long start = (long) httpServletRequest.getAttribute(startTimeKey);
         long elapsed = System.nanoTime() - start;
         double seconds = (double) elapsed / 1000000000.0;
-        requestLatency.labels(
-                serviceName,
-                httpServletRequest.getMethod(),
-                getMatchingURLPattern(httpServletRequest),
-                Integer.toString(httpServletResponse.getStatus())
-        ).observe(seconds);
+        String matchedUrl = getMatchingURLPattern(httpServletRequest);
+        if (!matchedUrl.equals("")) {
+            requestLatency.labels(
+                    serviceName,
+                    httpServletRequest.getMethod(),
+                    matchedUrl,
+                    Integer.toString(httpServletResponse.getStatus())
+            ).observe(seconds);
+        }
     }
 
     @Override
@@ -55,19 +70,30 @@ public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletRe
     }
 
     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();
+        String res = "";
+        for (PatternsRequestCondition pattern : getUrlPatterns()) {
+            if (pattern.getMatchingCondition(httpServletRequest) != null &&
+                    !httpServletRequest.getServletPath().equals("/error")) {
+                res = pattern.getMatchingCondition(httpServletRequest).getPatterns().iterator().next();
                 break;
             }
         }
         return res;
     }
+
+    private Set<PatternsRequestCondition> getUrlPatterns() {
+        if (this.urlPatterns == null) {
+            this.urlPatterns = new HashSet<>();
+            requestMappingHandlerMapping.getHandlerMethods().forEach((mapping, handlerMethod) ->
+                    urlPatterns.add(mapping.getPatternsCondition()));
+            RepositoryRestHandlerMapping repositoryRestHandlerMapping = new
+                    RepositoryRestHandlerMapping(mappings, repositoryConfiguration);
+            repositoryRestHandlerMapping.setJpaHelper(jpaHelper);
+            repositoryRestHandlerMapping.setApplicationContext(applicationContext);
+            repositoryRestHandlerMapping.afterPropertiesSet();
+            repositoryRestHandlerMapping.getHandlerMethods().forEach((mapping, handlerMethod) ->
+                    urlPatterns.add(mapping.getPatternsCondition()));
+        }
+        return this.urlPatterns;
+    }
 }