From 8aa583e7105cfde7adafe7786f7f3d251c78c5c1 Mon Sep 17 00:00:00 2001
From: Rob Zienert <rzienert@netflix.com>
Date: Wed, 31 May 2017 14:16:02 -0700
Subject: [PATCH] feat(ratelimit): Adding principal metrics

---
 .../gate/ratelimit/RateLimitingInterceptor.java    | 14 ++++++++++++++
 .../ratelimit/RateLimitingInterceptorSpec.groovy   |  6 ++----
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/gate-web/src/main/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptor.java b/gate-web/src/main/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptor.java
index 1b396f14ca..b3c9d67e54 100644
--- a/gate-web/src/main/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptor.java
+++ b/gate-web/src/main/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptor.java
@@ -15,8 +15,10 @@
  */
 package com.netflix.spinnaker.gate.ratelimit;
 
+import com.netflix.spectator.api.BasicTag;
 import com.netflix.spectator.api.Counter;
 import com.netflix.spectator.api.Registry;
+import com.netflix.spectator.api.Tag;
 import com.netflix.spinnaker.security.User;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -29,6 +31,7 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.time.ZonedDateTime;
+import java.util.Collections;
 
 public class RateLimitingInterceptor extends HandlerInterceptorAdapter {
 
@@ -38,6 +41,7 @@ public class RateLimitingInterceptor extends HandlerInterceptorAdapter {
 
   private RateLimiter rateLimiter;
   private RateLimitPrincipalProvider rateLimitPrincipalProvider;
+  private Registry registry;
 
   private Counter throttlingCounter;
   private Counter learningThrottlingCounter;
@@ -45,6 +49,7 @@ public class RateLimitingInterceptor extends HandlerInterceptorAdapter {
   public RateLimitingInterceptor(RateLimiter rateLimiter, Registry registry, RateLimitPrincipalProvider rateLimitPrincipalProvider) {
     this.rateLimiter = rateLimiter;
     this.rateLimitPrincipalProvider = rateLimitPrincipalProvider;
+    this.registry = registry;
     throttlingCounter = registry.counter("rateLimit.throttling");
     learningThrottlingCounter = registry.counter("rateLimit.throttlingLearning");
   }
@@ -69,6 +74,7 @@ public boolean preHandle(HttpServletRequest request, HttpServletResponse respons
     Rate rate = rateLimiter.incrementAndGetRate(principal);
 
     rate.assignHttpHeaders(response, principal.isLearning());
+    recordPrincipalMetrics(principal, rate);
 
     if (principal.isLearning()) {
       if (rate.isThrottled()) {
@@ -123,4 +129,12 @@ private String sourceIpAddress(HttpServletRequest request) {
     }
     return ip;
   }
+
+  private void recordPrincipalMetrics(RateLimitPrincipal principal, Rate rate) {
+    Iterable<Tag> tags = Collections.singletonList(new BasicTag("principal", principal.getName()));
+    if (rate.isThrottled()) {
+      registry.counter("rateLimit.principal.throttled", tags).increment();
+    }
+    registry.gauge("rateLimit.principal.remaining", tags, rate.remaining);
+  }
 }
diff --git a/gate-web/src/test/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptorSpec.groovy b/gate-web/src/test/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptorSpec.groovy
index 5304f8d8a0..19ef0499c5 100644
--- a/gate-web/src/test/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptorSpec.groovy
+++ b/gate-web/src/test/groovy/com/netflix/spinnaker/gate/ratelimit/RateLimitingInterceptorSpec.groovy
@@ -15,7 +15,7 @@
  */
 package com.netflix.spinnaker.gate.ratelimit
 
-import com.netflix.spectator.api.Counter
+import com.netflix.spectator.api.NoopRegistry
 import com.netflix.spectator.api.Registry
 import com.netflix.spinnaker.gate.config.RateLimiterConfiguration
 import com.netflix.spinnaker.security.User
@@ -30,9 +30,7 @@ import javax.servlet.http.HttpServletResponse
 
 class RateLimitingInterceptorSpec extends Specification {
 
-  Registry registry = Mock() {
-    counter(_) >> Mock(Counter)
-  }
+  Registry registry = new NoopRegistry()
 
   RateLimiter rateLimiter = Mock()