func (h *Headers) wrapResponseWriter(w http.ResponseWriter) http.ResponseWriter {
var newW = httputils.NewFlexibleResponseWriter(func(frw *httputils.FlexibleResponseWriter) {
httputils.CopyHeaders(frw.Header(), w.Header())
h.response.rewrite(w.Header())
frw.BodyWriter = utils.AddCloser(w)
w.WriteHeader(frw.Code)
})
httputils.CopyHeaders(w.Header(), newW.Header())
return newW
}
func (h *reqHandler) getResponseHook() func(*httputils.FlexibleResponseWriter) {
return func(rw *httputils.FlexibleResponseWriter) {
h.Logger.Debugf("[%p] Received headers for %s, sending them to client...", h.req, h.req.URL)
httputils.CopyHeadersWithout(rw.Headers, h.resp.Header(), hopHeaders...)
h.resp.WriteHeader(rw.Code)
isCacheable := cacheutils.IsResponseCacheable(rw.Code, rw.Headers)
if !isCacheable {
h.Logger.Debugf("[%p] Response is non-cacheable", h.req)
rw.BodyWriter = utils.AddCloser(h.resp)
return
}
expiresIn := cacheutils.ResponseExpiresIn(rw.Headers, h.CacheDefaultDuration)
if expiresIn <= 0 {
h.Logger.Debugf("[%p] Response expires in the past: %s", h.req, expiresIn)
rw.BodyWriter = utils.AddCloser(h.resp)
return
}
responseRange, err := httputils.GetResponseRange(rw.Code, rw.Headers)
if err != nil {
h.Logger.Debugf("[%p] Was not able to get response range (%s)", h.req, err)
rw.BodyWriter = utils.AddCloser(h.resp)
return
}
h.Logger.Debugf("[%p] Response is cacheable! Caching metadata and parts...", h.req)
code := rw.Code
if code == http.StatusPartialContent {
// 206 is returned only if the server would have returned 200 with a normal request
code = http.StatusOK
}
//!TODO: maybe call cached time.Now. See the comment in utils.IsMetadataFresh
now := time.Now()
obj := &types.ObjectMetadata{
ID: h.objID,
ResponseTimestamp: now.Unix(),
Code: code,
Size: responseRange.ObjSize,
Headers: make(http.Header),
ExpiresAt: now.Add(expiresIn).Unix(),
}
httputils.CopyHeadersWithout(rw.Headers, obj.Headers, metadataHeadersToFilter...)
if obj.Headers.Get("Date") == "" { // maybe the server does not return date, we should set it then
obj.Headers.Set("Date", now.Format(http.TimeFormat))
}
//!TODO: consult the cache algorithm whether to save the metadata
//!TODO: optimize this, save the metadata only when it's newer
//!TODO: also, error if we already have fresh metadata but the received metadata is different
if err := h.Cache.Storage.SaveMetadata(obj); err != nil {
h.Logger.Errorf("[%p] Could not save metadata for %s: %s", h.req, obj.ID, err)
rw.BodyWriter = utils.AddCloser(h.resp)
return
}
if h.req.Method == "HEAD" {
rw.BodyWriter = utils.AddCloser(h.resp)
return
}
rw.BodyWriter = utils.MultiWriteCloser(
utils.AddCloser(h.resp),
PartWriter(h.Cache, h.objID, *responseRange),
)
h.Logger.Debugf("[%p] Setting the cached data to expire in %s", h.req, expiresIn)
h.Cache.Scheduler.AddEvent(
h.objID.Hash(),
storage.GetExpirationHandler(h.Cache, h.Logger, h.objID),
expiresIn,
)
}
}
