go-eureka-client
Non-offical implementation of Spring Cloud Eureka client.
Tips: Non-full-features, only some basic and useful features implemented.
Spring Cloud Eureka Configurations
| FEATURES | Support |
|---|---|
| AvailabilityZones | √ |
| ServiceUrl | √ |
| UseDnsForFetchingServiceUrls | √ |
| RegisterWithEureka | √ |
| PreferSameZoneEureka | √ |
| FilterOnlyUpInstances | √ |
| RegistryFetchIntervalSeconds | √ |
| FetchRegistry | √ |
| EurekaServerPort | √ |
| EurekaServerUrlContexts | √ |
go-eureka-client extended features
| FEATURES | Support |
|---|---|
| AutoUpdateDnsServiceUrls | √ |
| AutoUpdateDnsServiceUrlsIntervals | √ |
| HeartbeatIntervals | √ |
Samples
Sample 1
Get Eureka server urls from configuration, e.g:
config := eureka.GetDefaultEurekaClientConfig()
config.UseDnsForFetchingServiceUrls = false
config.Region = "region-cn-hd-1"
config.AvailabilityZones = map[string]string{
"region-cn-hd-1": "zone-cn-hz-1",
}
config.ServiceUrl = map[string]string{
"zone-cn-hz-1": "http://192.168.20.236:9001/eureka,http://192.168.20.237:9001/eureka",
}
// custom logger
//eureka.SetLogger(func(level int, format string, a ...interface{}) {
// if level == eureka.LevelError {
// fmt.Println("[custom logger error] " + format, a)
// }else {
// fmt.Println("[custom logger debug] " + format, a)
// }
//})
// run eureka client async
eureka.DefaultClient.Config(config).
Register("APP_ID_CLIENT_FROM_CONFIG", 9000).
Run()
select {}
Full sample code, refer to: samples/client_from_config.go
Sample 2
Get Eureka server urls from dns(TXT Record) lookup, e.g:
config := eureka.GetDefaultEurekaClientConfig()
config.UseDnsForFetchingServiceUrls = true
config.Region = "region-cn-hd-1"
config.AvailabilityZones = map[string]string{
"region-cn-hd-1": "zone-cn-hz-1",
}
config.EurekaServerDNSName = "dev.ms-registry.xf.io"
config.EurekaServerUrlContext = "eureka"
config.EurekaServerPort = "9001"
// custom logger
//eureka.SetLogger(func(level int, format string, a ...interface{}) {
// if level == eureka.LevelError {
// fmt.Println("[custom logger error] " + format, a)
// }else {
// fmt.Println("[custom logger debug] " + format, a)
// }
//})
// run eureka client async
eureka.DefaultClient.Config(config).
Register("APP_ID_CLIENT_FROM_DNS", 9000).
Run()
select {}
Full sample code, refer to: samples/client_from_dns.go
Sample 3
Eureka Server REST api util, e.g:
config := eureka.GetDefaultEurekaClientConfig()
config.UseDnsForFetchingServiceUrls = false
config.Region = "region-cn-hd-1"
config.AvailabilityZones = map[string]string{
"region-cn-hd-1": "zone-cn-hz-1",
}
config.ServiceUrl = map[string]string{
"zone-cn-hz-1": "http://192.168.20.236:9001/eureka,http://192.168.20.237:9001/eureka",
}
c := eureka.DefaultClient.Config(config)
api, err := c.Api()
if err != nil {
log.Fatalln("Failed to pick EurekaServerApi instance, err=", err.Error())
}
instances, err := api.QueryAllInstances()
if err != nil {
log.Fatalln("Failed to query all instances, err=", err.Error())
}
log.Println("all instances: ", instances)
Full sample code, refer to: samples/eureka_api_rest.go
Eureka server Rest api supported, refer to list below:
| Operation | HTTP action | Support |
|---|---|---|
| Register new application instance | POST /eureka/v2/apps/appID | √ |
| De-register application instance | DELETE /eureka/v2/apps/appID/instanceID | √ |
| Send application instance heartbeat | PUT /eureka/v2/apps/appID/instanceID | √ |
| Query for all instances | GET /eureka/v2/apps | √ |
| Query for all appID instances | GET /eureka/v2/apps/appID | √ |
| Query for a specific appID/instanceID | GET /eureka/v2/apps/appID/instanceID | √ |
| Query for a specific instanceID | GET /eureka/v2/instances/instanceID | √ |
| Take instance out of service | PUT /eureka/v2/apps/appID/instanceID/status?value=OUT_OF_SERVICE | √ |
| Move instance back into service (remove override) | DELETE /eureka/v2/apps/appID/instanceID/status?value=UP (The value=UP is optional, it is used as a suggestion for the fallback status due to removal of the override) | √ |
| Update metadata | PUT /eureka/v2/apps/appID/instanceID/metadata?key=value | √ |
| Query for all instances under a particular vip address | GET /eureka/v2/vips/vipAddress | × |
| Query for all instances under a particular secure vip address | GET /eureka/v2/svips/svipAddress | × |
Registry screenshots
Client heartbeat
