Fix https downgrade for pages behind proxy

We can't rely on r.TLS when pages are served behind proxy
So we save https flag to a context for later usage
Right now I'm trying to keep changes to a minimum since
I'm planning to backport this to older versions
That's why https flag is not refactored throughout the codebase

The alternative way would be to use gorilla's proxy headers
I'm planning to refactor to that version later

1 files changed, 4 insertions, 0 deletions

diff --git a/app.go b/app.go
index da1a5315..3efc22c2 100644
--- a/app.go
+++ b/app.go
@@ -26,6 +26,7 @@ import (
 	"gitlab.com/gitlab-org/gitlab-pages/internal/domain"
 	"gitlab.com/gitlab-org/gitlab-pages/internal/httperrors"
 	"gitlab.com/gitlab-org/gitlab-pages/internal/netutil"
+	"gitlab.com/gitlab-org/gitlab-pages/internal/request"
 	"gitlab.com/gitlab-org/gitlab-pages/metrics"
 )
 
@@ -230,6 +231,8 @@ func (a *theApp) serveFileOrNotFound(domain *domain.D) http.HandlerFunc {
 
 func (a *theApp) ServeHTTP(ww http.ResponseWriter, r *http.Request) {
 	https := r.TLS != nil
+	r = request.WithHTTPSFlag(r, https)
+
 	headerConfig.AddCustomHeaders(ww, a.CustomHeaders)
 
 	a.serveContent(ww, r, https)
@@ -238,6 +241,7 @@ func (a *theApp) ServeHTTP(ww http.ResponseWriter, r *http.Request) {
 func (a *theApp) ServeProxy(ww http.ResponseWriter, r *http.Request) {
 	forwardedProto := r.Header.Get(xForwardedProto)
 	https := forwardedProto == xForwardedProtoHTTPS
+	r = request.WithHTTPSFlag(r, https)
 
 	if forwardedHost := r.Header.Get(xForwardedHost); forwardedHost != "" {
 		r.Host = forwardedHost