hystrixgo

func (*CircuitBreaker) Do ¶

func (c *CircuitBreaker) Do(run RunLogic, fallback FallbackLogic, dataIn interface{}) (interface{}, error)

Do will execute synchronous with circuit breaker

Parameters:

1. run = required, defines either inline or external function to be executed, it is meant for a self contained function and accepts no parameter, returns error
2. fallback = optional, defines either inline or external function to be executed as fallback when run fails, it is meat for a self contained function and accepts only error parameter, returns error, set to nil if fallback is not specified
3. dataIn = optional, input parameter to run and fallback func, may be nil if not needed

func (*CircuitBreaker) DoC ¶

func (c *CircuitBreaker) DoC(ctx context.Context, run RunLogic, fallback FallbackLogic, dataIn interface{}) (interface{}, error)

DoC will execute synchronous with circuit breaker in given context

Parameters:

1. ctx = required, defines the context in which this method is to be run under
2. run = required, defines either inline or external function to be executed, it is meant for a self contained function and accepts context.Context parameter, returns error
3. fallback = optional, defines either inline or external function to be executed as fallback when run fails, it is meant for a self contained function and accepts context.Context and error parameters, returns error, set to nil if fallback is not specified
4. dataIn = optional, input parameter to run and fallback func, may be nil if not needed

func (*CircuitBreaker) FlushAll ¶

func (c *CircuitBreaker) FlushAll()

FlushAll purges ALL circuits and metrics from memory across the ENTIRE PROCESS, not just the circuits owned by this CircuitBreaker instance. This is a limitation of afex/hystrix-go's package-level circuit registry — there is no exported API to flush or remove a single named circuit. Callers should be aware that invoking this method on any CircuitBreaker instance will reset every circuit breaker in the process. A per-instance flush requires replacing hystrix-go (see P2-5).

func (*CircuitBreaker) Go ¶

func (c *CircuitBreaker) Go(run RunLogic,
	fallback FallbackLogic,
	dataIn interface{}) (interface{}, error)

Go will execute async with circuit breaker

Parameters:

1. run = required, defines either inline or external function to be executed, it is meant for a self contained function and accepts no parameter, returns error
2. fallback = optional, defines either inline or external function to be executed as fallback when run fails, it is meat for a self contained function and accepts only error parameter, returns error, set to nil if fallback is not specified
3. dataIn = optional, input parameter to run and fallback func, may be nil if not needed

func (*CircuitBreaker) GoC ¶

func (c *CircuitBreaker) GoC(ctx context.Context,
	run RunLogic,
	fallback FallbackLogic,
	dataIn interface{}) (interface{}, error)

GoC will execute async with circuit breaker in given context

Parameters:

1. ctx = required, defines the context in which this method is to be run under
2. run = required, defines either inline or external function to be executed, it is meant for a self contained function and accepts context.Context parameter, returns error
3. fallback = optional, defines either inline or external function to be executed as fallback when run fails, it is meat for a self contained function and accepts context.Context and error parameters, returns error, set to nil if fallback is not specified
4. dataIn = optional, input parameter to run and fallback func, may be nil if not needed

func (*CircuitBreaker) Init ¶

func (c *CircuitBreaker) Init() error

Init will initialize the circuit break with the given command name, a command name represents a specific service or api method that has circuit breaker being applied

func (*CircuitBreaker) StartStatsdCollector ¶

func (c *CircuitBreaker) StartStatsdCollector(appName string, statsdIp string, statsdPort ...int) error

StartStatsdCollector will register and initiate the hystrixgo package for metric collection into statsd, each action from hystrixgo will be tracked into metrics and pushed into statsd via udp

Parameters:

1. appName = name of the app working with hystrixgo
2. statsdIp = IP address of statsd service host
3. statsdPort = Port of statsd service host

statsd and graphite is a service that needs to be running on a host, either localhost or another reachable host in linux, the easiest way to deploy statsd and graphite is via docker image:

see full docker install info at = https://github.com/graphite-project/docker-graphite-statsd

docker command to run statsd and graphite as a unit as follows:

docker run -d --name graphite --restart=always -p 80:80 -p 2003-2004:2003-2004 -p 2023-2024:2023-2024 -p 8125:8125/udp -p 8126:8126 graphiteapp/graphite-statsd

once docker image is running, to view graphite:

http://localhost/dashboard

func (*CircuitBreaker) StartStreamHttpServer ¶

func (c *CircuitBreaker) StartStreamHttpServer(port ...int) error

StartStreamHttpServer will start a simple HTTP server on local host with given port, this will launch in goroutine, and return immediately

This method call is on entire hystrixgo package, not just the current circuit breaker struct ¶

To view stream data, launch browser, point to http://localhost:port

default port = 81

func (*CircuitBreaker) StopStreamHttpServer ¶

func (c *CircuitBreaker) StopStreamHttpServer()

StopStreamHttpServer will stop the currently running stream server if already started

func (*CircuitBreaker) UpdateConfig ¶

func (c *CircuitBreaker) UpdateConfig()

UpdateConfig will update the hystrixgo command config data to the current value in struct for a given command name

func (*CircuitBreaker) UpdateLogger ¶

func (c *CircuitBreaker) UpdateLogger()

UpdateLogger updates the PROCESS-GLOBAL hystrix-go logger based on the Logger field of this struct. WARNING: hystrix.SetLogger is package-level — the last caller wins for ALL circuits, not just this instance (see BL-2 / P2-5).