feat: filter级别降级处理

原因
    需要支持降级处理

修改
    修改filterHook, 支持降级

gateway-support-lib/pom.xml

@@ -45,6 +45,11 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-core</artifactId>
+            <version>1.8.0</version>
+        </dependency>
     </dependencies>
 
 </project>

gateway-support-lib/src/main/java/cn/axzo/foundation/gateway/support/plugin/impl/RequestFilterHook.java

@@ -1,5 +1,6 @@
 package cn.axzo.foundation.gateway.support.plugin.impl;
 
+import cn.axzo.foundation.exception.BusinessException;
 import cn.axzo.foundation.gateway.support.entity.GateResponse;
 import cn.axzo.foundation.gateway.support.entity.ProxyContext;
 import cn.axzo.foundation.gateway.support.entity.RequestContext;
@@ -8,6 +9,13 @@ import cn.axzo.foundation.gateway.support.plugin.impl.filters.*;
 import cn.axzo.foundation.util.FastjsonUtils;
 import cn.axzo.foundation.web.support.rpc.RequestParams;
 import cn.axzo.foundation.web.support.rpc.RpcClient;
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.SphU;
+import com.alibaba.csp.sentinel.Tracer;
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRule;
+import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRuleManager;
 import com.alibaba.fastjson.JSON;
 import com.alibaba.fastjson.JSONObject;
 import com.google.common.base.Preconditions;
@@ -15,6 +23,7 @@ import com.google.common.base.Splitter;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
 import lombok.*;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
@@ -74,6 +83,17 @@ public class RequestFilterHook implements ProxyHook {
             .put("requestParamCheckFilter", new RequestParamCheckFilter())
             .put("moveInputFieldFilter", new MoveInputFieldFilter())
             .put("keyNoQueryFilter", new KeyNoQueryFilter())
+            .put("emptyFilter", new RequestFilter() {
+                @Override
+                public JSON filterIn(RequestContext reqContext, JSON params, JSONObject config) {
+                    return RequestFilter.super.filterIn(reqContext, params, config);
+                }
+
+                @Override
+                public JSON filterOut(RequestContext reqContext, JSON response, JSONObject config) {
+                    return RequestFilter.super.filterOut(reqContext, response, config);
+                }
+            })
             .build();
 
     @Builder
@@ -103,9 +123,32 @@ public class RequestFilterHook implements ProxyHook {
         for (FilterBean bean : beans) {
             RequestFilter requestFilter = filterBeanResolver.apply(bean.getName());
             Preconditions.checkState(requestFilter != null, bean.getName() + " 没在系统注册");
-            requestBody = requestFilter.filterIn(reqContext, requestBody, bean.getConfig());
+            FallBackConfig fallBackConfig = bean.getFallBackConfig();
-        }
 
+            Entry entry = null;
+            try {
+                if (fallBackConfig != null) {
+                    String resourceName = bean.getResourceName(reqContext.getRequestURI());
+                    fallBackConfig.registerRule(resourceName);
+                    entry = SphU.entry(resourceName, EntryType.IN);
+                }
+                requestBody = requestFilter.filterIn(reqContext, requestBody, bean.getConfig());
+            } catch (BlockException ex) {
+                //降级处理
+                requestBody = filterBeanResolver.apply(fallBackConfig.getFallBackFilter())
+                        .filterIn(reqContext, requestBody, fallBackConfig.getConfig());
+            } catch (Exception ex) {
+                //非业务异常记录trace
+                if (!BusinessException.class.isAssignableFrom(ex.getClass())) {
+                    Tracer.traceEntry(ex, entry);
+                }
+                throw ex;
+            } finally {
+                if (entry != null) {
+                    entry.exit();
+                }
+            }
+        }
         // 只支持 json 格式
         return ((RequestParams.BodyParams) postParams).toBuilder().content(requestBody).build();
     }
@@ -133,7 +176,31 @@ public class RequestFilterHook implements ProxyHook {
         for (FilterBean bean : beans) {
             RequestFilter requestFilter = filterBeanResolver.apply(bean.getName());
             Preconditions.checkState(requestFilter != null, bean.getName() + " 没在系统注册");
+            FallBackConfig fallBackConfig = bean.getFallBackConfig();
+
+            Entry entry = null;
+            try {
+                if (fallBackConfig != null) {
+                    String resourceName = bean.getResourceName(reqContext.getRequestURI());
+                    fallBackConfig.registerRule(resourceName);
+                    entry = SphU.entry(resourceName, EntryType.OUT);
+                }
                 responseBody = requestFilter.filterOut(reqContext, responseBody, bean.getConfig());
+            } catch (BlockException ex) {
+                //降级处理
+                responseBody = filterBeanResolver.apply(fallBackConfig.getFallBackFilter())
+                        .filterIn(reqContext, responseBody, fallBackConfig.getConfig());
+            } catch (Exception ex) {
+                //非业务异常记录trace
+                if (!BusinessException.class.isAssignableFrom(ex.getClass())) {
+                    Tracer.traceEntry(ex, entry);
+                }
+                throw ex;
+            } finally {
+                if (entry != null) {
+                    entry.exit();
+                }
+            }
         }
 
         GateResponse res = response.toBuilder().build();
@@ -195,5 +262,49 @@ public class RequestFilterHook implements ProxyHook {
     private static class FilterBean {
         private String name;
         private JSONObject config;
+
+        public FallBackConfig getFallBackConfig() {
+            return Optional.ofNullable(config)
+                    .flatMap(e -> Optional.ofNullable(e.getJSONObject("fallBack"))
+                            .map(fallBack -> fallBack.toJavaObject(FallBackConfig.class)))
+                    .orElse(null);
+        }
+
+        public String getResourceName(String requestUrl) {
+            return "RequestFilterHook:" + name + "@" + requestUrl;
+        }
+    }
+
+    @Data
+    @Builder
+    @NoArgsConstructor
+    @AllArgsConstructor
+    private static class FallBackConfig {
+        String fallBackFilter = "emptyFilter";
+        JSONObject config;
+        /** 策略, 支持FLOW_GRADE_QPS慢查询比例, DEGRADE_GRADE_EXCEPTION_RATIO异常比例, DEGRADE_GRADE_EXCEPTION_COUNT异常数 */
+        Integer grade = 2;
+        /** 默认10s内请求大于5个, 同时错误超过一半则降级30s */
+        Double count = 0.5D;
+        Integer timeWindow = 30;
+        Integer minRequestAmount = 5;
+        /** 慢比例有效 */
+        Double slowRatioThreshold = 1.0;
+        Integer statIntervalMs = 10000;
+
+        public void registerRule(String resourceName) {
+            if (DegradeRuleManager.hasConfig(resourceName)) {
+                return;
+            }
+            DegradeRule degradeRule = new DegradeRule(resourceName);
+            degradeRule.setGrade(grade);
+            degradeRule.setCount(count);
+            degradeRule.setTimeWindow(timeWindow);
+            degradeRule.setMinRequestAmount(minRequestAmount);
+            degradeRule.setSlowRatioThreshold(slowRatioThreshold);
+            degradeRule.setStatIntervalMs(statIntervalMs);
+
+            DegradeRuleManager.setRulesForResource(resourceName, ImmutableSet.of(degradeRule));
+        }
     }
 }

gateway-support-lib/src/test/java/cn/axzo/foundation/gateway/support/plugin/impl/RequestFilterHookTest.java

@@ -0,0 +1,57 @@
+package cn.axzo.foundation.gateway.support.plugin.impl;
+
+
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.SphU;
+import com.alibaba.csp.sentinel.Tracer;
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRule;
+import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRuleManager;
+import com.google.common.collect.ImmutableSet;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+class RequestFilterHookTest {
+
+
+    public static void main(String[] args) {
+
+        String resourceName = "aaaa";
+
+        DegradeRule degradeRule = new DegradeRule(resourceName);
+        degradeRule.setGrade(2);
+        degradeRule.setCount(0.5);
+        degradeRule.setTimeWindow(30);
+        degradeRule.setMinRequestAmount(5);
+        degradeRule.setStatIntervalMs(10);
+
+        DegradeRuleManager.setRulesForResource(resourceName, ImmutableSet.of(degradeRule));
+
+        List<Integer> blocked = IntStream.range(0, 20).mapToObj(e -> {
+                    Entry entry = null;
+                    try {
+                        entry = SphU.entry(resourceName, EntryType.IN);
+                        if (e % 2 == 0) {
+                            throw new RuntimeException();
+                        }
+                        return e;
+                    } catch (BlockException ex) {
+                        return -1;
+                    } catch (Exception ex) {
+                        Tracer.traceEntry(ex, entry);
+                        return -2;
+                    } finally {
+                        if (entry != null) {
+                            entry.exit();
+                        }
+                    }
+                })
+                .collect(Collectors.toList());
+
+        System.out.printf(blocked.toString());
+    }
+
+}