Method ServeHTTP

storage/remote/read_handler.go:71–114

(w http.ResponseWriter, r *http.Request)

}

func (h *readHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	if err := h.remoteReadGate.Start(ctx); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	h.queries.Inc()

	defer h.remoteReadGate.Done()
	defer h.queries.Dec()

	req, err := DecodeReadRequest(r)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	externalLabels := h.config().GlobalConfig.ExternalLabels.Map()

	sortedExternalLabels := make([]prompb.Label, 0, len(externalLabels))
	for name, value := range externalLabels {
		sortedExternalLabels = append(sortedExternalLabels, prompb.Label{
			Name:  name,
			Value: value,
		})
	}
	slices.SortFunc(sortedExternalLabels, func(a, b prompb.Label) int {
		return strings.Compare(a.Name, b.Name)
	})

	responseType, err := NegotiateResponseType(req.AcceptedResponseTypes)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	switch responseType {
	case prompb.ReadRequest_STREAMED_XOR_CHUNKS:
		h.remoteReadStreamedXORChunks(ctx, w, req, externalLabels, sortedExternalLabels)
	default:
		// On empty or unknown types in req.AcceptedResponseTypes we default to non streamed, raw samples response.
		h.remoteReadSamples(ctx, w, req, externalLabels, sortedExternalLabels)
	}
}

func (h *readHandler) remoteReadSamples(
	ctx context.Context,