diff --git a/plugin/cache/handler.go b/plugin/cache/handler.go index 350ec0bb0..2dd3c0646 100644 --- a/plugin/cache/handler.go +++ b/plugin/cache/handler.go @@ -39,39 +39,28 @@ func (c *Cache) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) ttl = i.ttl(now) } if i == nil { - if !do { - setDo(rc) - } crr := &ResponseWriter{ResponseWriter: w, Cache: c, state: state, server: server, do: do} - return plugin.NextOrFailure(c.Name(), c.Next, ctx, crr, rc) + return c.doRefresh(ctx, state, crr) } if ttl < 0 { servedStale.WithLabelValues(server).Inc() // Adjust the time to get a 0 TTL in the reply built from a stale item. now = now.Add(time.Duration(ttl) * time.Second) - addr := w.LocalAddr() // See https://github.com/coredns/coredns/issues/4271, unclear how, but pull this out of the goroutine, and get the address here. - go func() { - if !do { - setDo(rc) - } - crr := &ResponseWriter{Cache: c, state: state, server: server, prefetch: true, remoteAddr: addr, do: do} - plugin.NextOrFailure(c.Name(), c.Next, ctx, crr, rc) - }() + cw := newPrefetchResponseWriter(server, state, c) + go c.doPrefetch(ctx, state, cw, i, now) + } else if c.shouldPrefetch(i, now) { + cw := newPrefetchResponseWriter(server, state, c) + go c.doPrefetch(ctx, state, cw, i, now) } resp := i.toMsg(r, now, do) w.WriteMsg(resp) - if c.shouldPrefetch(i, now) { - go c.doPrefetch(ctx, state, server, i, now) - } return dns.RcodeSuccess, nil } -func (c *Cache) doPrefetch(ctx context.Context, state request.Request, server string, i *item, now time.Time) { - cw := newPrefetchResponseWriter(server, state, c) - - cachePrefetches.WithLabelValues(server).Inc() - plugin.NextOrFailure(c.Name(), c.Next, ctx, cw, state.Req) +func (c *Cache) doPrefetch(ctx context.Context, state request.Request, cw *ResponseWriter, i *item, now time.Time) { + cachePrefetches.WithLabelValues(cw.server).Inc() + c.doRefresh(ctx, state, cw) // When prefetching we loose the item i, and with it the frequency // that we've gathered sofar. See we copy the frequencies info back @@ -81,6 +70,13 @@ func (c *Cache) doPrefetch(ctx context.Context, state request.Request, server st } } +func (c *Cache) doRefresh(ctx context.Context, state request.Request, cw *ResponseWriter) (int, error) { + if !state.Do() { + setDo(state.Req) + } + return plugin.NextOrFailure(c.Name(), c.Next, ctx, cw, state.Req) +} + func (c *Cache) shouldPrefetch(i *item, now time.Time) bool { if c.prefetch <= 0 { return false