package healthcheck import ( "context" "net/http" "net/http/httptest" "net/url" "sync" "testing" "time" "github.com/containous/traefik/testhelpers" "github.com/vulcand/oxy/roundrobin" ) const healthCheckInterval = 100 * time.Millisecond type testHandler struct { done func() healthSequence []bool } func TestSetBackendsConfiguration(t *testing.T) { tests := []struct { desc string startHealthy bool healthSequence []bool wantNumRemovedServers int wantNumUpsertedServers int wantGaugeValue float64 }{ { desc: "healthy server staying healthy", startHealthy: true, healthSequence: []bool{true}, wantNumRemovedServers: 0, wantNumUpsertedServers: 0, wantGaugeValue: 1, }, { desc: "healthy server becoming sick", startHealthy: true, healthSequence: []bool{false}, wantNumRemovedServers: 1, wantNumUpsertedServers: 0, wantGaugeValue: 0, }, { desc: "sick server becoming healthy", startHealthy: false, healthSequence: []bool{true}, wantNumRemovedServers: 0, wantNumUpsertedServers: 1, wantGaugeValue: 1, }, { desc: "sick server staying sick", startHealthy: false, healthSequence: []bool{false}, wantNumRemovedServers: 0, wantNumUpsertedServers: 0, wantGaugeValue: 0, }, { desc: "healthy server toggling to sick and back to healthy", startHealthy: true, healthSequence: []bool{false, true}, wantNumRemovedServers: 1, wantNumUpsertedServers: 1, wantGaugeValue: 1, }, } for _, test := range tests { test := test t.Run(test.desc, func(t *testing.T) { t.Parallel() // The context is passed to the health check and canonically cancelled by // the test server once all expected requests have been received. ctx, cancel := context.WithCancel(context.Background()) defer cancel() ts := newTestServer(cancel, test.healthSequence) defer ts.Close() lb := &testLoadBalancer{RWMutex: &sync.RWMutex{}} backend := NewBackendHealthCheck(Options{ Path: "/path", Interval: healthCheckInterval, LB: lb, }, "backendName") serverURL := testhelpers.MustParseURL(ts.URL) if test.startHealthy { lb.servers = append(lb.servers, serverURL) } else { backend.disabledURLs = append(backend.disabledURLs, serverURL) } collectingMetrics := testhelpers.NewCollectingHealthCheckMetrics() check := HealthCheck{ Backends: make(map[string]*BackendHealthCheck), metrics: collectingMetrics, } wg := sync.WaitGroup{} wg.Add(1) go func() { check.execute(ctx, backend) wg.Done() }() // Make test timeout dependent on number of expected requests, health // check interval, and a safety margin. timeout := time.Duration(len(test.healthSequence)*int(healthCheckInterval) + 500) select { case <-time.After(timeout): t.Fatal("test did not complete in time") case <-ctx.Done(): wg.Wait() } lb.Lock() defer lb.Unlock() if lb.numRemovedServers != test.wantNumRemovedServers { t.Errorf("got %d removed servers, wanted %d", lb.numRemovedServers, test.wantNumRemovedServers) } if lb.numUpsertedServers != test.wantNumUpsertedServers { t.Errorf("got %d upserted servers, wanted %d", lb.numUpsertedServers, test.wantNumUpsertedServers) } if collectingMetrics.Gauge.GaugeValue != test.wantGaugeValue { t.Errorf("got %v ServerUp Gauge, want %v", collectingMetrics.Gauge.GaugeValue, test.wantGaugeValue) } }) } } func TestNewRequest(t *testing.T) { tests := []struct { desc string host string port int path string expected string }{ { desc: "no port override", host: "backend1:80", port: 0, path: "/test", expected: "http://backend1:80/test", }, { desc: "port override", host: "backend2:80", port: 8080, path: "/test", expected: "http://backend2:8080/test", }, { desc: "no port override with no port in host", host: "backend1", port: 0, path: "/health", expected: "http://backend1/health", }, { desc: "port override with no port in host", host: "backend2", port: 8080, path: "/health", expected: "http://backend2:8080/health", }, } for _, test := range tests { test := test t.Run(test.desc, func(t *testing.T) { t.Parallel() backend := NewBackendHealthCheck( Options{ Path: test.path, Port: test.port, }, "backendName") u := &url.URL{ Scheme: "http", Host: test.host, } req, err := backend.newRequest(u) if err != nil { t.Fatalf("failed to create new backend request: %s", err) } actual := req.URL.String() if actual != test.expected { t.Fatalf("got %s for healthcheck URL, wanted %s", actual, test.expected) } }) } } type testLoadBalancer struct { // RWMutex needed due to parallel test execution: Both the system-under-test // and the test assertions reference the counters. *sync.RWMutex numRemovedServers int numUpsertedServers int servers []*url.URL } func (lb *testLoadBalancer) RemoveServer(u *url.URL) error { lb.Lock() defer lb.Unlock() lb.numRemovedServers++ lb.removeServer(u) return nil } func (lb *testLoadBalancer) UpsertServer(u *url.URL, options ...roundrobin.ServerOption) error { lb.Lock() defer lb.Unlock() lb.numUpsertedServers++ lb.servers = append(lb.servers, u) return nil } func (lb *testLoadBalancer) Servers() []*url.URL { return lb.servers } func (lb *testLoadBalancer) removeServer(u *url.URL) { var i int var serverURL *url.URL for i, serverURL = range lb.servers { if *serverURL == *u { break } } lb.servers = append(lb.servers[:i], lb.servers[i+1:]...) } func newTestServer(done func(), healthSequence []bool) *httptest.Server { handler := &testHandler{ done: done, healthSequence: healthSequence, } return httptest.NewServer(handler) } // ServeHTTP returns 200 or 503 HTTP response codes depending on whether the // current request is marked as healthy or not. // It calls the given 'done' function once all request health indicators have // been depleted. func (th *testHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { if len(th.healthSequence) == 0 { panic("received unexpected request") } healthy := th.healthSequence[0] if healthy { w.WriteHeader(http.StatusOK) } else { w.WriteHeader(http.StatusServiceUnavailable) } th.healthSequence = th.healthSequence[1:] if len(th.healthSequence) == 0 { th.done() } }