package handlers import ( "io/ioutil" "net/http" "net/http/httptest" "os" "testing" "time" "github.com/docker/distribution/configuration" "github.com/docker/distribution/context" "github.com/docker/distribution/health" ) func TestFileHealthCheck(t *testing.T) { interval := time.Second tmpfile, err := ioutil.TempFile(os.TempDir(), "healthcheck") if err != nil { t.Fatalf("could not create temporary file: %v", err) } defer tmpfile.Close() config := configuration.Configuration{ Storage: configuration.Storage{ "inmemory": configuration.Parameters{}, }, Health: configuration.Health{ FileCheckers: []configuration.FileChecker{ { Interval: interval, File: tmpfile.Name(), }, }, }, } ctx := context.Background() app := NewApp(ctx, config) healthRegistry := health.NewRegistry() app.RegisterHealthChecks(healthRegistry) // Wait for health check to happen <-time.After(2 * interval) status := healthRegistry.CheckStatus() if len(status) != 1 { t.Fatal("expected 1 item in health check results") } if status[tmpfile.Name()] != "file exists" { t.Fatal(`did not get "file exists" result for health check`) } os.Remove(tmpfile.Name()) <-time.After(2 * interval) if len(healthRegistry.CheckStatus()) != 0 { t.Fatal("expected 0 items in health check results") } } func TestHTTPHealthCheck(t *testing.T) { interval := time.Second threshold := 3 stopFailing := make(chan struct{}) checkedServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { if r.Method != "HEAD" { t.Fatalf("expected HEAD request, got %s", r.Method) } select { case <-stopFailing: w.WriteHeader(http.StatusOK) default: w.WriteHeader(http.StatusInternalServerError) } })) config := configuration.Configuration{ Storage: configuration.Storage{ "inmemory": configuration.Parameters{}, }, Health: configuration.Health{ HTTPCheckers: []configuration.HTTPChecker{ { Interval: interval, URI: checkedServer.URL, Threshold: threshold, }, }, }, } ctx := context.Background() app := NewApp(ctx, config) healthRegistry := health.NewRegistry() app.RegisterHealthChecks(healthRegistry) for i := 0; ; i++ { <-time.After(interval) status := healthRegistry.CheckStatus() if i < threshold-1 { // definitely shouldn't have hit the threshold yet if len(status) != 0 { t.Fatal("expected 1 item in health check results") } continue } if i < threshold+1 { // right on the threshold - don't expect a failure yet continue } if len(status) != 1 { t.Fatal("expected 1 item in health check results") } if status[checkedServer.URL] != "downstream service returned unexpected status: 500" { t.Fatal("did not get expected result for health check") } break } // Signal HTTP handler to start returning 200 close(stopFailing) <-time.After(2 * interval) if len(healthRegistry.CheckStatus()) != 0 { t.Fatal("expected 0 items in health check results") } }