Do not lookup domain for healthcheck requets350-do-not-lookup-domain-for-healthcheck

There is none anyway and with the gitlab source this is causing
redundant API requests.

Related to https://gitlab.com/gitlab-org/gitlab-pages/issues/350.

2 files changed, 56 insertions, 1 deletions

diff --git a/app.go b/app.go
index 312d171f..a454076d 100644
--- a/app.go
+++ b/app.go
@@ -88,6 +88,13 @@ func (a *theApp) redirectToHTTPS(w http.ResponseWriter, r *http.Request, statusC
 
 func (a *theApp) getHostAndDomain(r *http.Request) (string, *domain.Domain, error) {
 	host := request.GetHostWithoutPort(r)
+
+	// For healthcheck check requests we
+	// do not need to lookup the domain
+	if a.isHealthCheckRequest(r) {
+		return host, nil, nil
+	}
+
 	domain, err := a.domain(host)
 
 	return host, domain, err
@@ -125,7 +132,7 @@ func (a *theApp) checkAuthenticationIfNotExists(domain *domain.Domain, w http.Re
 
 func (a *theApp) tryAuxiliaryHandlers(w http.ResponseWriter, r *http.Request, https bool, host string, domain *domain.Domain) bool {
 	// short circuit content serving to check for a status page
-	if r.RequestURI == a.appConfig.StatusPath {
+	if a.isHealthCheckRequest(r) {
 		a.healthCheck(w, r, https)
 		return true
 	}
@@ -468,3 +475,7 @@ func runApp(config appConfig) {
 func fatal(err error, message string) {
 	log.WithError(err).Fatal(message)
 }
+
+func (a *theApp) isHealthCheckRequest(r *http.Request) bool {
+	return r.RequestURI == a.appConfig.StatusPath
+}
diff --git a/app_test.go b/app_test.go
index d78d6737..a98d30a7 100644
--- a/app_test.go
+++ b/app_test.go
@@ -4,6 +4,7 @@ import (
 	"crypto/tls"
 	"fmt"
 	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -58,3 +59,46 @@ func newGetRequestWithScheme(t *testing.T, scheme string, withTLS bool) *http.Re
 
 	return req
 }
+
+func TestIsHealthCheckRequest(t *testing.T) {
+	tests := []struct {
+		name          string
+		path          string
+		isHealthcheck bool
+	}{
+		{
+			name:          "Not a healthcheck request",
+			path:          "/foo/bar",
+			isHealthcheck: false,
+		},
+		{
+			name:          "Healthcheck request",
+			path:          "/-/healthcheck",
+			isHealthcheck: true,
+		},
+	}
+
+	app := theApp{}
+	app.appConfig.StatusPath = "/-/healthcheck"
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			r := httptest.NewRequest("GET", tc.path, nil)
+			require.Equal(t, tc.isHealthcheck, app.isHealthCheckRequest(r))
+		})
+	}
+}
+
+func TestGetHostAndDomainDoNotLookupDomainForHealthCheckRequest(t *testing.T) {
+	app := theApp{}
+	app.appConfig.StatusPath = "/-/healthcheck"
+
+	r := httptest.NewRequest("GET", "/-/healthcheck", nil)
+	r.Host = "gitlab.com"
+
+	host, domain, err := app.getHostAndDomain(r)
+
+	require.Equal(t, "gitlab.com", host)
+	require.Nil(t, domain)
+	require.NoError(t, err)
+}