traefik/provider/eureka/eureka.go
2017-07-20 14:59:54 +02:00

146 lines
3.6 KiB
Go

package eureka
import (
"io/ioutil"
"strconv"
"strings"
"text/template"
"time"
"github.com/ArthurHlt/go-eureka-client/eureka"
"github.com/cenk/backoff"
"github.com/containous/traefik/job"
"github.com/containous/traefik/log"
"github.com/containous/traefik/provider"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
)
// Provider holds configuration of the Provider provider.
type Provider struct {
provider.BaseProvider `mapstructure:",squash"`
Endpoint string `description:"Eureka server endpoint"`
Delay string `description:"Override default configuration time between refresh"`
}
// Provide allows the eureka provider to provide configurations to traefik
// using the given configuration channel.
func (p *Provider) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool, _ types.Constraints) error {
operation := func() error {
configuration, err := p.buildConfiguration()
if err != nil {
log.Errorf("Failed to build configuration for Provider, error: %s", err)
return err
}
configurationChan <- types.ConfigMessage{
ProviderName: "eureka",
Configuration: configuration,
}
var delay time.Duration
if len(p.Delay) > 0 {
var err error
delay, err = time.ParseDuration(p.Delay)
if err != nil {
log.Errorf("Failed to parse delay for Provider, error: %s", err)
return err
}
} else {
delay = time.Second * 30
}
ticker := time.NewTicker(delay)
safe.Go(func() {
for t := range ticker.C {
log.Debug("Refreshing Provider " + t.String())
configuration, err := p.buildConfiguration()
if err != nil {
log.Errorf("Failed to refresh Provider configuration, error: %s", err)
return
}
configurationChan <- types.ConfigMessage{
ProviderName: "eureka",
Configuration: configuration,
}
}
})
return nil
}
notify := func(err error, time time.Duration) {
log.Errorf("Provider connection error %+v, retrying in %s", err, time)
}
err := backoff.RetryNotify(operation, job.NewBackOff(backoff.NewExponentialBackOff()), notify)
if err != nil {
log.Errorf("Cannot connect to Provider server %+v", err)
return err
}
return nil
}
// Build the configuration from Provider server
func (p *Provider) buildConfiguration() (*types.Configuration, error) {
var EurekaFuncMap = template.FuncMap{
"getPort": p.getPort,
"getProtocol": p.getProtocol,
"getWeight": p.getWeight,
"getInstanceID": p.getInstanceID,
}
eureka.GetLogger().SetOutput(ioutil.Discard)
client := eureka.NewClient([]string{
p.Endpoint,
})
applications, err := client.GetApplications()
if err != nil {
return nil, err
}
templateObjects := struct {
Applications []eureka.Application
}{
applications.Applications,
}
configuration, err := p.GetConfiguration("templates/eureka.tmpl", EurekaFuncMap, templateObjects)
if err != nil {
log.Error(err)
}
return configuration, nil
}
func (p *Provider) getPort(instance eureka.InstanceInfo) string {
if instance.SecurePort.Enabled {
return strconv.Itoa(instance.SecurePort.Port)
}
return strconv.Itoa(instance.Port.Port)
}
func (p *Provider) getProtocol(instance eureka.InstanceInfo) string {
if instance.SecurePort.Enabled {
return "https"
}
return "http"
}
func (p *Provider) getWeight(instance eureka.InstanceInfo) string {
if val, ok := instance.Metadata.Map[types.LabelWeight]; ok {
return val
}
return "0"
}
func (p *Provider) getInstanceID(instance eureka.InstanceInfo) string {
if val, ok := instance.Metadata.Map[types.LabelBackendID]; ok {
return val
}
return strings.Replace(instance.IpAddr, ".", "-", -1) + "-" + p.getPort(instance)
}