Remove mirroring impact in accesslog

This commit is contained in:
Julien Salleyron 2019-12-09 15:12:06 +01:00 committed by Traefiker Bot
parent e0f265db15
commit d2e458f673

View file

@ -8,6 +8,7 @@ import (
"net/http" "net/http"
"sync" "sync"
"github.com/containous/traefik/v2/pkg/middlewares/accesslog"
"github.com/containous/traefik/v2/pkg/safe" "github.com/containous/traefik/v2/pkg/safe"
) )
@ -63,11 +64,21 @@ func (m *Mirroring) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
if handler.count*100 < total*uint64(handler.percent) { if handler.count*100 < total*uint64(handler.percent) {
handler.count++ handler.count++
handler.lock.Unlock() handler.lock.Unlock()
// In ServeHTTP, we rely on the presence of the accesslog datatable found in the
// request's context to know whether we should mutate said datatable (and
// contribute some fields to the log). In this instance, we do not want the mirrors
// mutating (i.e. changing the service name in) the logs related to the mirrored
// server. Especially since it would result in unguarded concurrent reads/writes on
// the datatable. Therefore, we reset any potential datatable key in the new
// context that we pass around.
ctx := context.WithValue(req.Context(), accesslog.DataTableKey, nil)
// When a request served by m.handler is successful, req.Context will be canceled, // When a request served by m.handler is successful, req.Context will be canceled,
// which would trigger a cancellation of the ongoing mirrored requests. // which would trigger a cancellation of the ongoing mirrored requests.
// Therefore, we give a new, non-cancellable context to each of the mirrored calls, // Therefore, we give a new, non-cancellable context to each of the mirrored calls,
// so they can terminate by themselves. // so they can terminate by themselves.
handler.ServeHTTP(m.rw, req.WithContext(contextStopPropagation{req.Context()})) handler.ServeHTTP(m.rw, req.WithContext(contextStopPropagation{ctx}))
} else { } else {
handler.lock.Unlock() handler.lock.Unlock()
} }