Example #1
1
// Round trips the request to one of the endpoints and returns the response.
func (l *HttpLocation) RoundTrip(req request.Request) (*http.Response, error) {
	// Get options and transport as one single read transaction.
	// Options and transport may change if someone calls SetOptions
	o, tr := l.GetOptionsAndTransport()
	originalRequest := req.GetHttpRequest()

	//  Check request size first, if that exceeds the limit, we don't bother reading the request.
	if l.isRequestOverLimit(req) {
		return nil, errors.FromStatus(http.StatusRequestEntityTooLarge)
	}

	// Read the body while keeping this location's limits in mind. This reader controls the maximum bytes
	// to read into memory and disk. This reader returns anerror if the total request size exceeds the
	// prefefined MaxSizeBytes. This can occur if we got chunked request, in this case ContentLength would be set to -1
	// and the reader would be unbounded bufio in the http.Server
	body, err := netutils.NewBodyBufferWithOptions(originalRequest.Body, netutils.BodyBufferOptions{
		MemBufferBytes: o.Limits.MaxMemBodyBytes,
		MaxSizeBytes:   o.Limits.MaxBodyBytes,
	})
	if err != nil {
		return nil, err
	}
	if body == nil {
		return nil, fmt.Errorf("Empty body")
	}

	// Set request body to buffered reader that can replay the read and execute Seek
	req.SetBody(body)
	// Note that we don't change the original request Body as it's handled by the http server
	defer body.Close()

	for {
		_, err := req.GetBody().Seek(0, 0)
		if err != nil {
			return nil, err
		}

		endpoint, err := l.loadBalancer.NextEndpoint(req)
		if err != nil {
			log.Errorf("Load Balancer failure: %s", err)
			return nil, err
		}

		// Adds headers, changes urls. Note that we rewrite request each time we proxy it to the
		// endpoint, so that each try gets a fresh start
		req.SetHttpRequest(l.copyRequest(originalRequest, req.GetBody(), endpoint))

		// In case if error is not nil, we allow load balancer to choose the next endpoint
		// e.g. to do request failover. Nil error means that we got proxied the request successfully.
		response, err := l.proxyToEndpoint(tr, &o, endpoint, req)
		if o.ShouldFailover(req) {
			continue
		} else {
			return response, err
		}
	}
	log.Errorf("All endpoints failed!")
	return nil, fmt.Errorf("All endpoints failed")
}
Example #2
0
func convertError(err error) errors.ProxyError {
	switch e := err.(type) {
	case errors.ProxyError:
		return e
	case net.Error:
		if e.Timeout() {
			return errors.FromStatus(http.StatusRequestTimeout)
		}
	case *netutils.MaxSizeReachedError:
		return errors.FromStatus(http.StatusRequestEntityTooLarge)
	}
	return errors.FromStatus(http.StatusBadGateway)
}
Example #3
0
// Round trips the request to the selected location and writes back the response
func (p *Proxy) proxyRequest(w http.ResponseWriter, r *http.Request) error {

	// Create a unique request with sequential ids that will be passed to all interfaces.
	req := request.NewBaseRequest(r, atomic.AddInt64(&p.lastRequestId, 1), nil)
	location, err := p.router.Route(req)
	if err != nil {
		return err
	}

	// Router could not find a matching location, we can do nothing else.
	if location == nil {
		log.Errorf("%s failed to route", req)
		return errors.FromStatus(http.StatusBadGateway)
	}

	response, err := location.RoundTrip(req)
	if response != nil {
		netutils.CopyHeaders(w.Header(), response.Header)
		w.WriteHeader(response.StatusCode)
		io.Copy(w, response.Body)
		response.Body.Close()
		return nil
	} else {
		return err
	}
}
Example #4
0
// Accepts requests, round trips it to the endpoint, and writes back the response.
func (p *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	// Record the request body so we can replay it on errors.
	body, err := netutils.NewBodyBuffer(r.Body)
	if err != nil || body == nil {
		log.Errorf("Request read error %s", err)
		if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
			p.replyError(errors.FromStatus(http.StatusRequestTimeout), w, r)
		} else {
			p.replyError(errors.FromStatus(http.StatusBadRequest), w, r)
		}
		return
	}
	defer body.Close()
	r.Body = body

	req := request.NewBaseRequest(r, atomic.AddInt64(&p.lastRequestId, 1), body)

	err = p.proxyRequest(w, req)
	if err != nil {
		log.Errorf("%s failed: %s", req, err)
		p.replyError(err, w, r)
	}
}
Example #5
0
// Helper function to reply with http errors
func (p *Proxy) replyError(err error, w http.ResponseWriter, req *http.Request) {
	// Discard the request body, so that clients can actually receive the response
	// otherwise they can only see lost connection
	// TODO: actually check this
	proxyError, ok := err.(errors.ProxyError)
	if !ok {
		proxyError = errors.FromStatus(http.StatusBadGateway)
	}

	io.Copy(ioutil.Discard, req.Body)
	statusCode, body, contentType := p.options.ErrorFormatter.Format(proxyError)
	w.Header().Set("Content-Type", contentType)
	w.WriteHeader(statusCode)
	w.Write(body)
}
Example #6
0
// Round trips the request to the selected location and writes back the response
func (p *Proxy) proxyRequest(w http.ResponseWriter, req *request.BaseRequest) error {
	location, err := p.router.Route(req)
	if err != nil {
		return err
	}
	// Router could not find a matching location, we can do nothing more
	if location == nil {
		log.Errorf("%s failed to route", req)
		return errors.FromStatus(http.StatusBadGateway)
	}
	response, err := location.RoundTrip(req)
	if response != nil {
		netutils.CopyHeaders(w.Header(), response.Header)
		w.WriteHeader(response.StatusCode)
		io.Copy(w, response.Body)
		defer response.Body.Close()
		return nil
	} else {
		return err
	}
}
Example #7
0
// Accepts requests, round trips it to the endpoint and writes backe the response.
func (p *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	// Record the request body so we can replay it on errors.
	body, err := netutils.NewBodyBuffer(r.Body)
	if err != nil || body == nil {
		log.Errorf("Request read error %s", err)
		p.replyError(errors.FromStatus(http.StatusBadRequest), w, r)
		return
	}
	defer body.Close()
	r.Body = body

	req := &request.BaseRequest{
		HttpRequest: r,
		Id:          atomic.AddInt64(&p.lastRequestId, 1),
		Body:        body,
	}

	err = p.proxyRequest(w, req)
	if err != nil {
		log.Errorf("%s failed: %s", req, err)
		p.replyError(err, w, r)
	}
}