Chaos Monkey with Springboot

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PRINCIPLES OF CHAOS ENGINEERING

• https://principlesofchaos.org/?lang=ENcontent

Chaos Monkey the solution, based on the idea behind Nelflix's tool, designed to test Spring Boot applications. There are two required steps for enabling Chaos Monkey for a Spring Boot application.

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First, let's add the library chaos-monkey-spring-boot to the project's dependencies.

	<dependency>
		<groupId>de.codecentric</groupId>
		<artifactId>chaos-monkey-spring-boot</artifactId>
		<version>2.2.0</version>
	</dependency>

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Then, we should activate the profile chaos-monkey on application startup.

      -  spring.profiles.active=chaos-monkey

      - $ java -jar target/order-service-1.0-SNAPSHOT.jar --spring.profiles.active=chaos-monkey

      - inside eclipse enable profile 

Enable Spring Boot Actuator Endpoints

		management:
		  endpoint:
			chaosmonkey:
			  enabled: true
		  endpoints:
			web:
			  exposure:
				include: health,info,chaosmonkey

or

End point

    management.endpoint.chaosmonkey.enabled: true
    management.endpoint.chaosmonkeyjmx.enabled=true

inlcude all endpoints

 management.endpoints.web.exposure.include=*

include specific endpoints

 management.endpoints.web.exposure.include=health,info,metrics,chaosmonkey

---

http://localhost:8080/students

http://localhost:8080/student?id=10001

---

GET

http://localhost:8080/actuator/chaosmonkey

		{
		   "chaosMonkeyProperties":{
			  "enabled":true
		   },
		   "assaultProperties":{
			  "level":5,
			  "latencyRangeStart":10000,
			  "latencyRangeEnd":15000,
			  "latencyActive":false,
			  "exceptionsActive":false,
			  "exception":{
				 "type":null,
				 "arguments":null
			  },
			  "killApplicationActive":false,
			  "memoryActive":false,
			  "memoryMillisecondsHoldFilledMemory":90000,
			  "memoryMillisecondsWaitNextIncrease":1000,
			  "memoryFillIncrementFraction":0.15,
			  "memoryFillTargetFraction":0.25,
			  "runtimeAssaultCronExpression":"OFF",
			  "watchedCustomServices":null
		   },
		   "watcherProperties":{
			  "controller":true,
			  "restController":true,
			  "service":true,
			  "repository":true,
			  "component":false
		   }
		}

GET

http://localhost:8080/actuator/chaosmonkey/status

  Ready to be evil!

POST

http://localhost:8080/actuator/chaosmonkey/enable

POST

http://localhost:8080/actuator/chaosmonkey/disable

GET

http://localhost:8080/actuator/chaosmonkey/watchers

		{
		"controller": true,
		"restController": false,
		"service": true,
		"repository": false,
		"component": false
		}

GET

http://localhost:8080/actuator/chaosmonkey/assaults

		{
		   "level":5,
		   "latencyRangeStart":10000,
		   "latencyRangeEnd":15000,
		   "latencyActive":false,
		   "exceptionsActive":false,
		   "exception":{
			  "type":null,
			  "arguments":null
		   },
		   "killApplicationActive":false,
		   "memoryActive":false,
		   "memoryMillisecondsHoldFilledMemory":90000,
		   "memoryMillisecondsWaitNextIncrease":1000,
		   "memoryFillIncrementFraction":0.15,
		   "memoryFillTargetFraction":0.25,
		   "runtimeAssaultCronExpression":"OFF",
		   "watchedCustomServices":null
		}

Exception

POST

http://localhost:8080/actuator/chaosmonkey/assaults

		{
		"level": 3,
		"latencyRangeStart": 20000,
		"latencyRangeEnd": 50000,
		"latencyActive": false,
		"exceptionsActive": true,
		"killApplicationActive": false,
		"exception": {
			"type": "java.lang.IllegalArgumentException",
			"arguments": [
			   {
				"className": "java.lang.String",
				 "value": "custom illegal argument exception"
				}
			  ] 
			 }
		}

Latency

POST

http://localhost:8080/actuator/chaosmonkey/assaults

		{
		"level": 1,
		"latencyRangeStart": 20000,
		"latencyRangeEnd": 50000,
		"latencyActive": true,
		"exceptionsActive": false,
		"killApplicationActive": false,
		"restartApplicationActive":false
		}

Method test

You can customize the behavior of all watchers using the property watchedCustomServices and decide which classes and public methods should be attacked. If no signatures are stored, all classes and public methods, recognized by the watchers are attacked by default.You can either maintain the list in your application properties or adjust it at runtime using the Spring Boot Actuator Endpoint.

POST

http://localhost:8080/actuator/chaosmonkey/assaults \

		{
		"level": 1,
		"latencyRangeStart": 20000,
		"latencyRangeEnd": 50000,
		"latencyActive": true,
		"exceptionsActive": false,
		"killApplicationActive": false,
		"restartApplicationActive":false,
		"watchedCustomServices": ["com.khan.vaquar.demo.controller.StudentController.findAll"]

		}

After adding assult in findAll method you can see only latancy inside of findAll method

        http://localhost:8080/students

Other methods are working without issue

        http://localhost:8080/student?id=10001            

Same logic applicable to exceptions :

		{
				"level": 1,
				"latencyRangeStart": 20000,
				"latencyRangeEnd": 50000,
				"latencyActive": false,
				"exceptionsActive": true,
						"exception": {
					"type": "java.lang.IllegalArgumentException",
					"arguments": [
					   {
						"className": "java.lang.String",
						 "value": "custom illegal argument exception"
						}
					  ] 
					 },

				"killApplicationActive": false,
				"restartApplicationActive":false,
				"watchedCustomServices": ["com.khan.vaquar.demo.controller.StudentController.findAll"]

				}

After adding assult in findAll method you can see only exception inside of findAll method

        http://localhost:8080/students

Other methods are working without issue

        http://localhost:8080/student?id=10001 

POST

http://localhost:8080/actuator/chaosmonkey/assaults \

		{
		"level": 1,
		"latencyRangeStart": 1000,
		"latencyRangeEnd": 3000,
		"latencyActive": true,
		"exceptionsActive": false,
		"killApplicationActive": false,
		"memoryActive": false,
		"memoryMillisecondsHoldFilledMemory": 90000,
		"memoryMillisecondsWaitNextIncrease": 1000,
		"memoryFillIncrementFraction": 0.15,
		"memoryFillTargetFraction": 0.25,
		"runtimeAssaultCronExpression": "OFF",
		"watchedCustomServices": null
		}

or

		{
		"level": 2,
		"latencyRangeStart": 1000,
		"latencyRangeEnd": 3000,
		"latencyActive": true,
		"exceptionsActive": false,
		"killApplicationActive": false,
		"memoryActive": true,
		"memoryMillisecondsHoldFilledMemory": 90000,
		"memoryMillisecondsWaitNextIncrease": 1000,
		"memoryFillIncrementFraction": 99.10,
		"memoryFillTargetFraction": 99.10,
		"runtimeAssaultCronExpression": "OFF",
		"watchedCustomServices": null
		}

POST

http://localhost:8080/actuator/chaosmonkey/assaults

		{
			"latencyRangeStart": 2000,
			"latencyRangeEnd": 5000,
			"latencyActive": true,
			"exceptionsActive": false,
			"killApplicationActive": false
		}

POST

http://localhost:8080/actuator/chaosmonkey/assaults

		{
			"latencyActive": false,
			"exceptionsActive": true,
			"killApplicationActive": false
		}

POST

http://localhost:8080/actuator/chaosmonkey/assaults

		{
			"latencyActive": false,
			"exceptionsActive": false,
			"killApplicationActive": true
		}



		{
		"chaosMonkeyProperties":{
		"enabled": true
		},
		"assaultProperties":{
		"level": 3,
		"latencyRangeStart": 1000,
		"latencyRangeEnd": 3000,
		"latencyActive": true,
		"exceptionsActive": false,
		"killApplicationActive": false,
		"watchedCustomServices": []
		},
		"watcherProperties":{
		"controller": true,
		"restController": false,
		"service": true,
		"repository": false,
		"component": false
		}
		}

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What is Chaos Eng -introductions including how to start your first chaos experiment:

https://www.gremlin.com/community/tutorials/chaos-engineering-the-history-principles-and-practice/

Good summary of people, tools, companies doing chaos experiments:

https://coggle.it/diagram/WiKceGDAwgABrmyv/t/chaos-engineeringcompanies%2C-people%2C-tools-practices/0a2d4968c94723e48e1256e67df51d0f4217027143924b23517832f53c536e62

Tools:

ChaosMonkey for SpringBoot: https://docs.chaostoolkit.org/drivers/cloudfoundry/. Very easy to follow instructions. Easy to turn on/off using Spring profile.

Spinnaker: https://www.spinnaker.io/. Netflix Chaos Monkey does not support deployments that are managed by anything other than Spinnaker. That makes it pretty hard to use Chaos Monkey from Netflix.

Chaos Toolkit - https://docs.chaostoolkit.org/drivers/cloudfoundry/. This tool is particularly helpful to my situation since my applications are deployed in Cloud Foundry and this tool has a CloudFoundry extension. Pretty elaborate, but easy to follow instructions. My preferred tool so far.

Chaos Lemur - https://content.pivotal.io/blog/chaos-lemur-testing-high-availability-on-pivotal-cloud-foundry. This tool has promise but network admin won't share AWS credentials for me to muck with Pivotal cells.

Gramlin -https://www.gremlin.com/

• https://www.youtube.com/watch?v=-smx0-qeurw
• https://www.youtube.com/embed/cefJd2v037U
• https://netflix.github.io/chaosmonkey/
• https://chaostoolkit.org/
• https://codecentric.github.io/chaos-monkey-spring-boot/

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