Handler chain¶
概述¶
处理链中包含一系列handler, 在一次调用中可以通过扩展调用链的方式来插入定制的逻辑处理,如何开发新的Handler,可参考Developer Guide,本章节只讨论如何进行配置,以及框架已经实现的handler有哪些
配置¶
cse:
protocols:
{name}:
handler:
Consumer:
{name}:{handler_names}
Provider:
{name}:{handler_names}
Consumer表示,当你要调用别的服务时,会通过的处理链Provider表示,当你被别人调用人,会通过的处理链支持在Consumer和Provider中定义多个不同的chain name当handler配置为空,那么框架会自动为Consumer与Provider加载默认的handlers,chain的名称为default当handler配置不为空,那么在Provider链中,如果protocol有相同名称的chain,对应的protocol服务将加载相同名称的chain,如果protocol没有配置相同名称的chain,那么该协议将默认加载名称为default的chain
Consumer的默认chain为¶
名称 功能
ratelimiter-consumer 客户端限流
router 路由策略
loadbalance 负载均衡
tracing-consumer 客户端调用链追踪
transport 各协议客户端处理请求,如果你使用自定义处理链配置,那么结尾处必须加入这个handler
API¶
当处理链配置为空,用户也可自定义自己的默认处理链
//SetDefaultConsumerChains your custom chain map for Consumer,if there is no config, this default chain will take affect
func SetDefaultConsumerChains(c map[string]string)
//SetDefaultProviderChains set your custom chain map for Provider,if there is no config, this default chain will take affect
func SetDefaultProviderChains(c map[string]string)
you can check build-in handler list in handler.go the const part shows handler list
const (
//consumer chain
Transport = "transport"
Loadbalance = "loadbalance"
BizkeeperConsumer = "bizkeeper-consumer"
TracingConsumer = "tracing-consumer"
RatelimiterConsumer = "ratelimiter-consumer"
Router = "router"
FaultInject = "fault-inject"
//provider chain
RatelimiterProvider = "ratelimiter-provider"
TracingProvider = "tracing-provider"
BizkeeperProvider = "bizkeeper-provider"
)
实例¶
自定义了custom-handler,放入到默认链中¶
handler:
chain:
Consumer:
default: custom-handler, bizkeeper-consumer, router, loadbalance, ratelimiter-consumer,transport
为不同协议定制不同的链¶
protocols:
rest:
listenAddress: 127.0.0.1:5001
rest-admin:
listenAddress: 127.0.0.1:5002
highway:
listenAddress: 127.0.0.1:5003
grpc:
listenAddress: 127.0.0.1:5004
handler:
chain:
Provider:
rest: custom-handler, ratelimiter-provider
highway: tracing-provider
如上配置,rest协议将会加载rest chain,highway协议将会加载highway chain。由于rest-admin与grpc协议没有配置相同名称的chain,所以他们将默认加载default chain