func (h *reqHandler) getUpstreamReader(start, end uint64) io.ReadCloser {
subh := *h
subh.req = subh.getNormalizedRequest()
subh.req.Header.Set("Range", fmt.Sprintf("bytes=%d-%d", start, end))
h.Logger.Debugf("[%p] Making upstream request for %s, bytes [%d-%d]...",
subh.req, subh.req.URL, start, end)
//!TODO: optimize requests for the same pieces? if possible, make only 1 request to the upstream for the same part
r, w := io.Pipe()
subh.resp = httputils.NewFlexibleResponseWriter(func(rw *httputils.FlexibleResponseWriter) {
respRng, err := httputils.GetResponseRange(rw.Code, rw.Headers)
if err != nil {
h.Logger.Debugf("[%p] Could not parse the content-range for the partial upstream request: %s", subh.req, err)
_ = w.CloseWithError(err)
}
h.Logger.Debugf("[%p] Received response with status %d and range %v", subh.req, rw.Code, respRng)
if rw.Code == http.StatusPartialContent {
//!TODO: check whether the returned range corresponds to the requested range
rw.BodyWriter = w
} else if rw.Code == http.StatusOK {
//!TODO: handle this, use skipWriter or something like that
_ = w.CloseWithError(fmt.Errorf("NOT IMPLEMENTED"))
} else {
_ = w.CloseWithError(fmt.Errorf("Upstream responded with status %d", rw.Code))
}
})
go utils.SafeExecute(
subh.carbonCopyProxy,
func(err error) {
h.Logger.Errorf("[%p] Panic inside carbonCopyProxy %s", subh.req, err)
w.CloseWithError(err) // !TODO maybe some other error
},
)
return newWholeChunkReadCloser(r, h.Cache.PartSize.Bytes())
}
func safeExecute(f func(), key types.ObjectIDHash) {
utils.SafeExecute(f, func(err error) {
log.Printf("panic inside the function for key '%s' : %s", key, err)
})
}