[ 
https://issues.apache.org/jira/browse/SCB-324?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16379706#comment-16379706
 ] 

ASF GitHub Bot commented on SCB-324:
------------------------------------

wujimin commented on a change in pull request #543: [SCB-324] Fault-Injection 
handler implementation
URL: 
https://github.com/apache/incubator-servicecomb-java-chassis/pull/543#discussion_r171132244
 
 

 ##########
 File path: 
handlers/handler-fault-injection/src/main/java/org/apache/servicecomb/faultinjection/FaultInjectionHandler.java
 ##########
 @@ -0,0 +1,222 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.servicecomb.faultinjection;
+
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.apache.servicecomb.core.Handler;
+import org.apache.servicecomb.core.Invocation;
+import org.apache.servicecomb.swagger.invocation.AsyncResponse;
+import org.apache.servicecomb.swagger.invocation.context.HttpStatus;
+import org.apache.servicecomb.swagger.invocation.exception.CommonExceptionData;
+import org.apache.servicecomb.swagger.invocation.exception.InvocationException;
+import static org.apache.servicecomb.faultinjection.FaultInjectionConst.*;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Fault injection handler which injects the delay/abort for requests based on
+ * the percentage configured in service file.
+ *
+ */
+public class FaultInjectionHandler implements Handler {
+  private static final Logger LOGGER = 
LoggerFactory.getLogger(FaultInjectionHandler.class);
+
+  @Override
+  public void handle(Invocation invocation, AsyncResponse asyncResp) throws 
Exception {
+
+    //if no transport then call next handler.
+    if ((invocation.getTransport() != null) && 
(invocation.getTransport().getName() != null)) {
+
+      // prepare the key and lookup for request count.
+      String key = invocation.getTransport().getName() + 
invocation.getMicroserviceQualifiedName();
+
+      AtomicLong reqCount = FaultInjectionUtil.getOperMetTotalReq(key);
+      long reqCountCurrent = reqCount.get();
+      // increment the request count here after checking the delay/abort 
condition.
+      reqCount.incrementAndGet();
+
+      // get the config values related to delay percentage.
+      int delayPercent = getFaultInjectionConfig(invocation,
+          "delay.percent",
+          FAULT_INJECTION_DELAY_PERCENTAGE_DEFAULT);
+
+      // check fault delay condition.
+      boolean isDelay = checkFaultInjectionDelayAndAbort(reqCountCurrent, 
delayPercent);
+      if (isDelay) {
+        LOGGER.info("delay is added for the request by fault inject handler");
+        long delay = getFaultInjectionConfig(invocation,
+            "delay.fixedDelay",
+            FAULT_INJECTION_DELAY_DEFAULT);
+
+        Thread.sleep(delay);
+      }
+
+      // get the config values related to delay.
+      int abortPercent = getFaultInjectionConfig(invocation,
+          "abort.percent",
+          FAULT_INJECTION_ABORT_PERCENTAGE_DEFAULT);
+
+      // check fault delay condition.
+      boolean isAbort = checkFaultInjectionDelayAndAbort(reqCountCurrent, 
abortPercent);
+      if (isAbort) {
+        // get the config values related to delay percentage.
+        int errorCode = getFaultInjectionConfig(invocation,
+            "abort.httpStatus",
+            FAULT_INJECTION_ABORT_ERROR_MSG_DEFAULT);
+        // if request need to be abort then return failure with given error 
code
+        CommonExceptionData errorData = new CommonExceptionData("aborted by 
fault inject");
+        asyncResp.consumerFail(
+            new InvocationException(new HttpStatus(errorCode, "aborted by 
fault inject"), errorData));
+        return;
+      }
+    }
+
+    // if no delay and no abort then continue to next handler.
+    invocation.next(asyncResp);
+  }
+
+  /**
+   * It will check the delay/abort condition based on request count and 
percentage
+   * received.
+   * 
+   * @param reqCount
+   * @param percentage
+   * @param key
+   * @return true/false
+   */
+  private boolean checkFaultInjectionDelayAndAbort(long reqCount, int 
percentage) {
+    /*
+     * Example: delay/abort percentage configured is 10% and Get the 
count(suppose
+     * if it is 10th request) from map and calculate resultNew(10th request) 
and
+     * requestOld(9th request). Like this for every request it will calculate
+     * current request count and previous count. if both not matched need to 
add
+     * delay/abort otherwise no need to add.
+     */
+
+    // calculate the value with current request count.
+    long resultNew = (reqCount * percentage) / 100;
+
+    // calculate the value with previous count value.
+    long resultOld = ((reqCount - 1) * percentage) / 100;
+
+    // if both are not matching then delay/abort should be added.
+    if (resultNew != resultOld) {
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Handles the reading fault injection configuration.
+   * 
+   * @param invocation
+   *            invocation of request
+   * @param key
+   *            configuration key
+   * @return configuration value
+   */
+  private int getFaultInjectionConfig(Invocation invocation, String key, int 
defaultValue) {
+    int value = 0;
+    String config;
+    FaultInjectionConfig faultCfg = new FaultInjectionConfig();
+
+    //first need to check in config center map which has high priority.
+    Map<String, AtomicInteger> cfgMap = 
FaultInjectionUtil.getConfigCenterMap();
+
+    // get the config base on priority. 
operationName-->schema-->service-->global
+    String operationName = invocation.getOperationName();
+    String schema = invocation.getSchemaId();
+    String serviceName = invocation.getMicroserviceName();
+
+    if (operationName != null && schema != null && serviceName != null) {
 
 Review comment:
   never be null

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


> Chassis must support network failure simulation, so that I can developers can 
> enhance the robustness of the app
> ---------------------------------------------------------------------------------------------------------------
>
>                 Key: SCB-324
>                 URL: https://issues.apache.org/jira/browse/SCB-324
>             Project: Apache ServiceComb
>          Issue Type: Task
>          Components: Java-Chassis
>            Reporter: sukesh
>            Assignee: sukesh
>            Priority: Minor
>             Fix For: java-chassis-1.0.0-m1
>
>
> Add new handler for fault injection.
> 1) If handler 'fault-injection' is added in application property 
> file(microservice.yaml) then fault-injection handler should include in 
> handler chain.
> 2) When handler is called read the configuration and listen the configuration 
> event related to fault inject. The sample configuration file is in next slide.
> 3) The configuration mainly consist
>     -delay
>     -abort
>  *delay:*can set the delay for requests based on percentage configured. The 
> unit is ms. The delay percentage default value is 100%
>  *abort*: Abort the requests based on percentage configured. For rest 
> transport protocol error code can be configurable(500, 421) and highway 
> protocol does not support for error return. The abort percentage default 
> value is 100%
> 4) This features currently supports at consumer side.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to