feat:add min timeout metric strategy.

Author: SkyeBeFreeman

polaris-plugins/polaris-plugins-observability/stat-common/src/main/java/com/tencent/polaris/plugins/stat/common/model/MetricValueAggregationStrategyCollections.java

@@ -37,6 +37,7 @@ public class MetricValueAggregationStrategyCollections {
                 new UpstreamRequestSuccessStrategy(),
                 new UpstreamRequestTimeoutStrategy(),
                 new UpstreamRequestMaxTimeoutStrategy(),
+                new UpstreamRequestMinTimeoutStrategy(),
         };
 
         RATE_LIMIT_STRATEGY = new MetricValueAggregationStrategy[]{
@@ -180,6 +181,48 @@ public double initMetricValue(InstanceGauge dataSource) {
         }
     }
 
+    /**
+     * 服务调用最小时延
+     */
+    public static class UpstreamRequestMinTimeoutStrategy implements MetricValueAggregationStrategy<InstanceGauge> {
+
+        @Override
+        public String getStrategyDescription() {
+            return "minimum request delay per period";
+        }
+
+        @Override
+        public String getStrategyName() {
+            return "upstream_rq_min_timeout";
+        }
+
+        @Override
+        public void updateMetricValue(StatMetric targetValue, InstanceGauge dataSource) {
+            if (null == dataSource.getDelay()) {
+                return;
+            }
+
+            while (true) {
+                if (dataSource.getDelay() < targetValue.getValue()) {
+                    if (targetValue.compareAndSet((long) targetValue.getValue(), dataSource.getDelay())) {
+                        return;
+                    }
+                } else {
+                    return;
+                }
+            }
+        }
+
+        @Override
+        public double initMetricValue(InstanceGauge dataSource) {
+            if (null == dataSource.getDelay()) {
+                return 0.0;
+            }
+
+            return dataSource.getDelay();
+        }
+    }
+
     /**
      * 限流调用总请求数
      */

polaris-plugins/polaris-plugins-observability/stat-prometheus/src/test/java/com/tencent/polaris/plugins/stat/prometheus/plugin/PrometheusReporterTest.java

@@ -19,8 +19,6 @@
 
 import com.tencent.polaris.api.plugin.stat.CircuitBreakGauge;
 import com.tencent.polaris.api.plugin.stat.DefaultCircuitBreakResult;
-import com.tencent.polaris.api.plugin.stat.DefaultRateLimitResult;
-import com.tencent.polaris.api.plugin.stat.RateLimitGauge;
 import com.tencent.polaris.api.plugin.stat.StatInfo;
 import com.tencent.polaris.api.pojo.CircuitBreakerStatus;
 import com.tencent.polaris.api.pojo.InstanceGauge;
@@ -38,23 +36,17 @@
 import io.prometheus.client.Collector;
 import io.prometheus.client.Collector.MetricFamilySamples;
 import io.prometheus.client.CollectorRegistry;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Enumeration;
-import java.util.List;
-import java.util.Map;
-import java.util.Random;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.Executors;
-
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.junit.MockitoJUnitRunner;
 import org.slf4j.Logger;
 
+import java.util.*;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executors;
+
 @RunWith(MockitoJUnitRunner.Silent.class)
 public class PrometheusReporterTest {
 
@@ -198,7 +190,7 @@ public void testServiceCallSuccessStrategy() throws InterruptedException {
     }
 
     @Test
-    public void testServiceCallSumAndMaxStrategy() throws InterruptedException {
+    public void testServiceCallSumAndMaxAndMinStrategy() throws InterruptedException {
         List<Integer> delayList = Collections.synchronizedList(new ArrayList<>());
         int count = 20;
         batchDone(() -> {
@@ -216,18 +208,24 @@ public void testServiceCallSumAndMaxStrategy() throws InterruptedException {
         handler.destroy();
 
         int maxExpected = 0;
+        int minExpected = 10000;
         int sumExpected = 0;
         for (Integer i : delayList) {
             if (i > maxExpected) {
                 maxExpected = i;
             }
+            if (i < minExpected) {
+                minExpected = i;
+            }
             sumExpected += i;
         }
 
         ServiceCallResult example = mockFixedLabelServiceCallResult(200, 1000);
         Double maxResult = getServiceCallMaxResult(example);
+        Double minResult = getServiceCallMinResult(example);
         Double sumResult = getServiceCallSumResult(example);
         Assert.assertEquals(new Double(maxExpected), maxResult);
+        Assert.assertEquals(new Double(minExpected), minResult);
         Assert.assertEquals(new Double(sumExpected), sumResult);
     }
 
@@ -335,6 +333,11 @@ private Double getServiceCallMaxResult(ServiceCallResult example) {
                 new MetricValueAggregationStrategyCollections.UpstreamRequestMaxTimeoutStrategy());
     }
 
+    private Double getServiceCallMinResult(ServiceCallResult example) {
+        return getServiceCallResult(example,
+                new MetricValueAggregationStrategyCollections.UpstreamRequestMinTimeoutStrategy());
+    }
+
     private Double getServiceCallResult(ServiceCallResult example,
                                         MetricValueAggregationStrategy<InstanceGauge> strategy) {
         CollectorRegistry registry = handler.getPromRegistry();