func (r *RoundRobin) NextServer() (*url.URL, error) {
srv, err := r.nextServer()
if err != nil {
return nil, err
}
return utils.CopyURL(srv.url), nil
}
// In case if server is already present in the load balancer, returns error
func (rr *RoundRobin) UpsertServer(u *url.URL, options ...ServerOption) error {
rr.mutex.Lock()
defer rr.mutex.Unlock()
if u == nil {
return fmt.Errorf("server URL can't be nil")
}
if s, _ := rr.findServerByURL(u); s != nil {
for _, o := range options {
if err := o(s); err != nil {
return err
}
}
rr.resetState()
return nil
}
srv := &server{url: utils.CopyURL(u)}
for _, o := range options {
if err := o(srv); err != nil {
return err
}
}
if srv.weight == 0 {
srv.weight = defaultWeight
}
rr.servers = append(rr.servers, srv)
rr.resetState()
return nil
}
func (f *Forwarder) copyRequest(req *http.Request, u *url.URL) *http.Request {
outReq := new(http.Request)
*outReq = *req // includes shallow copies of maps, but we handle this below
outReq.URL = utils.CopyURL(req.URL)
outReq.URL.Scheme = u.Scheme
outReq.URL.Host = u.Host
outReq.URL.Opaque = req.RequestURI
// raw query is already included in RequestURI, so ignore it to avoid dupes
outReq.URL.RawQuery = ""
// Do not pass client Host header unless optsetter PassHostHeader is set.
if f.passHost != true {
outReq.Host = u.Host
}
outReq.Proto = "HTTP/1.1"
outReq.ProtoMajor = 1
outReq.ProtoMinor = 1
// Overwrite close flag so we can keep persistent connection for the backend servers
outReq.Close = false
outReq.Header = make(http.Header)
utils.CopyHeaders(outReq.Header, req.Header)
if f.rewriter != nil {
f.rewriter.Rewrite(outReq)
}
return outReq
}
func (s *Streamer) copyRequest(req *http.Request, body io.ReadCloser, bodySize int64) *http.Request {
o := *req
o.URL = utils.CopyURL(req.URL)
o.Header = make(http.Header)
utils.CopyHeaders(o.Header, req.Header)
o.ContentLength = bodySize
// remove TransferEncoding that could have been previously set because we have transformed the request from chunked encoding
o.TransferEncoding = []string{}
// http.Transport will close the request body on any error, we are controlling the close process ourselves, so we override the closer here
o.Body = ioutil.NopCloser(body)
return &o
}
func (rb *Rebalancer) upsertServer(u *url.URL, weight int) error {
if s, i := rb.findServer(u); i != -1 {
s.origWeight = weight
}
meter, err := rb.newMeter()
if err != nil {
return err
}
rbSrv := &rbServer{
url: utils.CopyURL(u),
origWeight: weight,
curWeight: weight,
meter: meter,
}
rb.servers = append(rb.servers, rbSrv)
return nil
}