Based on the. NET Core MicroServices framework-talk about service-tolerant degradation of surging

First, preface

For the soon-to-be open source surging by many. NET classmates, also by the. NET Core Learning Group, invited to join the. NET China Foundation to facilitate the promotion of domestic. NET core open source projects, I accepted the invitation to join the team to Exchange learning, and recently updated the new version of surging.

Update content:

1. Castle.core compatibility issue, the next version will be removed, to solve some users of the first compilation vs card death problem
2. Increased fault-tolerant demotion
3. Routing Fault-tolerant refactoring, for failed retries and failures without retries, failed callbacks,
4. Add some functional unit tests
5. Upgrade supports. NET CORE 2.0

Latest Address: https://github.com/dotnetcore/surging

Ii. Service-tolerant degradation Introduction and Example 1. Service-Tolerant Downgrade introduction

For the micro-service reliability mentioned in the previous article, for fault tolerance and degraded ellipsis, this article introduces fault tolerance and demotion

When microservices are not available, fault-tolerant processing is required based on the policies that are provisioned, and most of the fault tolerance and policies are public and therefore can be implemented in a framework.

Service Fault Tolerance

When the microservices call fails, the fault-tolerant mechanism can be used to realize the automatic fault-tolerant processing of microservices and improve the reliability of the system.

Surging fault tolerant strategies include:

Failure auto-switching mechanism (Failover): MicroServices invocation failure auto-switching policy refers to re-routing when a service invocation exception occurs, finding the next available microservices provider. When MicroServices are released, you can specify a cluster fault tolerance policy for the service. Consumers can override the general configuration of the service provider and implement a personalized fault-tolerant strategy.

Failure callback mechanism (injection): After a microservices call fails, provide an exception callback interface or inject script to execute the service consumer's custom failure handling logic.

Service downgrade

Service for some reason is not available, but the process can not directly fail, the need for local injection server implementation, such as the end of the year to purchase tickets 12306 large-scale access, resulting in the query train ticket service does not work properly, this time to do business to pass, return the last cache record or null, rather than return failure.

Common policies for demotion:

1, the service route short-circuit, directly return NULL. For example injection = "return null;".

3, service routing short-circuit, directly execute the local analog interface implementation class. injection = "true;".

Fault Tolerant Demotion

When the service is not available, you can service the business logic and let the service run properly

Automatic fault-tolerant demotion: The trigger is automatically matched against the defined Kanbao value, and the associated policy is called for demotion.

Forced demotion: triggered manually by operations based on the operation of the system.

2. Service Tolerance Degradation Example

Create a service fault tolerance downgrade, select injection policy script injection, and return null directly

[Command (strategy= strategytype.injection, injection = @ "return null;")]

Create a service fault tolerance downgrade, select injection policy script injection, and return directly to Task<usermodel>

[Command (strategy= strategytype.injection, injection = @ "Return Task.fromresult (new Surging.IModuleServices.Common.Models.UserModel         {            name= "" Fanly "",            age=18         

Create a service fault tolerance downgrade, select the injection policy direct local module call

Create a service fault tolerance downgrade, select the failover policy, and automatically switch to retry the remote call

Configuring related parameter lists

parameter	action	remarks
< P style= "margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px ">strategy	Fault tolerant strategy	Includes failover and injection
< P style= "margin-top:0px; margin-bottom:0px; padding-top:0px; padding-bottom:0px ">failovercluster	failover Count
Executiontimeoutinmilliseconds	Execution time-out	Default value: 1000
Requestcacheenabled	Whether to turn on caching	Default off
Injection	script injection	&NBSP;
	inject namespace
	error rate to achieve how many turn on fuse protection	default value:
Breakesleepwindowinmilliseconds	How many seconds after the fuse to try to request	Default value: 60000
Breakerforceclosed	Whether to force the fuse off
	at least how many requests fail within 10 seconds, the fuse is functioning	default value:
Maxconcurrentrequests	Maximum number of concurrent	10

Three. Testing

Test environment

Cpu:intel Core I7-4710MQ

Memory: 16G

HDD: 1T ssd+512g HDD

Network: LAN

The test results are as follows:

Iii. Summary

Surging next version to increase cache demotion, configure services for file fault tolerance, downgrade, and so on, add unit test, for API Gateway is developing, such as interested please pay more attention or join QQ Group: 615562965

Based on the. NET Core MicroServices framework-talk about service-tolerant degradation of surging