Function TestConsistentHashKey

loadbalancer/algorithm_test.go:389–418

(t *testing.T)

}

func TestConsistentHashKey(t *testing.T) {
	endpoints := []string{"http://127.0.0.1:8080", "http://127.0.0.2:8080", "http://127.0.0.3:8080"}
	ch := newConsistentHash(endpoints)

	r, _ := http.NewRequest("GET", "http://127.0.0.1:1234/foo", nil)
	r.RemoteAddr = "192.168.0.1:8765"

	rt := NewAlgorithmProvider().Do([]*routing.Route{{
		Route: eskip.Route{
			BackendType: eskip.LBBackend,
			LBAlgorithm: ConsistentHash.String(),
			LBEndpoints: eskip.NewLBEndpoints(endpoints),
		},
	}})[0]

	defaultEndpoint := ch.Apply(&routing.LBContext{Request: r, Route: rt, LBEndpoints: rt.LBEndpoints, Params: make(map[string]interface{})})
	remoteHostEndpoint := ch.Apply(&routing.LBContext{Request: r, Route: rt, LBEndpoints: rt.LBEndpoints, Params: map[string]interface{}{ConsistentHashKey: net.RemoteHost(r).String()}})

	if defaultEndpoint != remoteHostEndpoint {
		t.Error("remote host should be used as a default key")
	}

	for i, ep := range endpoints {
		key := fmt.Sprintf("%s-%d", ep, 1) // "ep-0" to "ep-99" is the range of keys for this endpoint. If we use this as the hash key it should select endpoint ep.
		selected := ch.Apply(&routing.LBContext{Request: r, Route: rt, LBEndpoints: rt.LBEndpoints, Params: map[string]interface{}{ConsistentHashKey: key}})
		if selected != rt.LBEndpoints[i] {
			t.Errorf("expected: %v, got %v", rt.LBEndpoints[i], selected)
		}
	}
}

func TestConsistentHashBoundedLoadDistribution(t *testing.T) {
	endpoints := []string{"http://127.0.0.1:8080", "http://127.0.0.2:8080", "http://127.0.0.3:8080"}