Merge pull request #65 from semyonslepov/master

Make server application context variable for DNS discovery

Author: Damian Turczyński

config.go

@@ -34,6 +34,7 @@ type eureka struct {
 	ServerDNSName         string   // default ""
 	ServiceUrls           []string // default []
 	ServerPort            int      // default 7001
+	ServerURLBase         string   // default "eureka/v2"
 	PollIntervalSeconds   int      // default 30
 	EnableDelta           bool     // TODO: Support querying for deltas
 	PreferSameZone        bool     // default false
@@ -67,4 +68,7 @@ func (c *Config) fillDefaults() {
 	if c.Eureka.PollIntervalSeconds == 0 {
 		c.Eureka.PollIntervalSeconds = 30
 	}
+	if len(c.Eureka.ServerURLBase) == 0 {
+		c.Eureka.ServerURLBase = "eureka/v2"
+	}
 }

connection.go

@@ -20,7 +20,7 @@ func (e *EurekaConnection) SelectServiceURL() string {
 		e.discoveryTtl = make(chan struct{}, 1)
 	}
 	if e.DNSDiscovery && len(e.discoveryTtl) == 0 {
-		servers, ttl, err := discoverDNS(e.DiscoveryZone, e.ServicePort)
+		servers, ttl, err := discoverDNS(e.DiscoveryZone, e.ServicePort, e.ServerURLBase)
 		if err != nil {
 			return choice(e.ServiceUrls)
 		}
@@ -68,6 +68,7 @@ func NewConnFromConfig(conf Config) (c EurekaConnection) {
 		log.Warning("UseDNSForServiceUrls is an experimental option")
 		c.DNSDiscovery = true
 		c.DiscoveryZone = conf.Eureka.DNSDiscoveryZone
+		c.ServerURLBase = conf.Eureka.ServerURLBase
 	}
 	return c
 }

dns_discover.go

@@ -14,7 +14,7 @@ const azURL = "http://169.254.169.254/latest/meta-data/placement/availability-zo
 
 var ErrNotInAWS = fmt.Errorf("Not in AWS")
 
-func discoverDNS(domain string, port int) (servers []string, ttl time.Duration, err error) {
+func discoverDNS(domain string, port int, urlBase string) (servers []string, ttl time.Duration, err error) {
 	r, _ := region()
 
 	// all DNS queries must use the FQDN
@@ -35,7 +35,7 @@ func discoverDNS(domain string, port int) (servers []string, ttl time.Duration,
 		}
 		for _, instance := range instances {
 			// format the service URL
-			servers = append(servers, fmt.Sprintf("http://%s:%d/eureka/v2", instance, port))
+			servers = append(servers, fmt.Sprintf("http://%s:%d/%s", instance, port, urlBase))
 		}
 	}
 	return

dns_discover_test.go

@@ -46,7 +46,7 @@ func TestGetNetflixTestDomain(t *testing.T) {
 		})
 	})
 	Convey("Autodiscover discoverytest.netflix.net.", t, func() {
-		servers, ttl, err := discoverDNS("discoverytest.netflix.net", 7001)
+		servers, ttl, err := discoverDNS("discoverytest.netflix.net", 7001, "")
 		So(ttl, ShouldEqual, 60*time.Second)
 		So(err, ShouldBeNil)
 		So(len(servers), ShouldEqual, 6)

struct.go

@@ -18,6 +18,7 @@ var EurekaURLSlugs = map[string]string{
 type EurekaConnection struct {
 	ServiceUrls    []string
 	ServicePort    int
+	ServerURLBase  string
 	Timeout        time.Duration
 	PollInterval   time.Duration
 	PreferSameZone bool