// This function alters the original request - adds/removes headers, removes hop headers,
// changes the request path.
func rewriteRequest(req *http.Request, cmd *command.Forward, upstream *command.Upstream) *http.Request {
outReq := new(http.Request)
*outReq = *req // includes shallow copies of maps, but we handle this below
outReq.URL.Scheme = upstream.Scheme
outReq.URL.Host = fmt.Sprintf("%s:%d", upstream.Host, upstream.Port)
if len(cmd.RewritePath) != 0 {
outReq.URL.Path = cmd.RewritePath
}
outReq.URL.RawQuery = req.URL.RawQuery
outReq.Proto = "HTTP/1.1"
outReq.ProtoMajor = 1
outReq.ProtoMinor = 1
outReq.Close = false
glog.Infof("Proxying request to: %v", outReq)
outReq.Header = make(http.Header)
netutils.CopyHeaders(outReq.Header, req.Header)
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
// TODO(pquerna): configure this? Not all backends properly parse the header..
if TRUST_FORWARD_HEADER {
if prior, ok := outReq.Header["X-Forwarded-For"]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
}
outReq.Header.Set("X-Forwarded-For", clientIP)
}
if req.TLS != nil {
outReq.Header.Set("X-Forwarded-Proto", "https")
} else {
outReq.Header.Set("X-Forwarded-Proto", "http")
}
if req.Host != "" {
outReq.Header.Set("X-Forwarded-Host", req.Host)
}
outReq.Header.Set("X-Forwarded-Server", vulcanHostname)
if len(cmd.RemoveHeaders) != 0 {
netutils.RemoveHeaders(cmd.RemoveHeaders, outReq.Header)
}
// Add generic instructions headers to the request
if len(cmd.AddHeaders) != 0 {
glog.Info("Proxying instructions headers:", cmd.AddHeaders)
netutils.CopyHeaders(outReq.Header, cmd.AddHeaders)
}
// Remove hop-by-hop headers to the backend. Especially
// important is "Connection" because we want a persistent
// connection, regardless of what the client sent to us.
netutils.RemoveHeaders(hopHeaders, outReq.Header)
return outReq
}
func MakeRequest(url string, opts Opts) (*http.Response, []byte, error) {
method := "GET"
if opts.Method != "" {
opts.Method = opts.Method
}
request, _ := http.NewRequest(method, url, strings.NewReader(opts.Body))
if opts.Headers != nil {
netutils.CopyHeaders(request.Header, opts.Headers)
}
if len(opts.Host) != 0 {
request.Host = opts.Host
}
var tr *http.Transport
if strings.HasPrefix(url, "https") {
tr = &http.Transport{
DisableKeepAlives: true,
TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
}
} else {
tr = &http.Transport{
DisableKeepAlives: true,
}
}
client := &http.Client{Transport: tr}
response, err := client.Do(request)
if err == nil {
bodyBytes, err := ioutil.ReadAll(response.Body)
return response, bodyBytes, err
}
return response, nil, err
}
// 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
}
}
func (l *HttpLocation) copyRequest(req *http.Request, body netutils.MultiReader, endpoint endpoint.Endpoint) *http.Request {
outReq := new(http.Request)
*outReq = *req // includes shallow copies of maps, but we handle this below
// Set the body to the enhanced body that can be re-read multiple times and buffered to disk
outReq.Body = body
endpointURL := endpoint.GetUrl()
outReq.URL.Scheme = endpointURL.Scheme
outReq.URL.Host = endpointURL.Host
outReq.URL.Opaque = req.RequestURI
// raw query is already included in RequestURI, so ignore it to avoid dupes
outReq.URL.RawQuery = ""
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)
netutils.CopyHeaders(outReq.Header, req.Header)
return outReq
}
func (w *WebhookSideEffect) Exec() error {
r, err := http.NewRequest(w.w.Method, w.w.URL, w.getBody())
if err != nil {
return err
}
if len(w.w.Headers) != 0 {
netutils.CopyHeaders(r.Header, w.w.Headers)
}
if len(w.w.Form) != 0 {
r.Header.Set("Content-Type", "application/x-www-form-urlencoded")
}
re, err := http.DefaultClient.Do(r)
if err != nil {
return err
}
if re.Body != nil {
defer re.Body.Close()
}
body, err := ioutil.ReadAll(re.Body)
if err != nil {
return err
}
log.Infof("%v got response: (%s): %s", w, re.Status, string(body))
return nil
}
func (tb *Recorder) ObserveRequest(req Request) {
tb.mutex.Lock()
defer tb.mutex.Unlock()
if len(tb.Header) != 0 {
netutils.CopyHeaders(req.GetHttpRequest().Header, tb.Header)
}
tb.ProcessedRequests = append(tb.ProcessedRequests, req)
}
func (tb *Recorder) ProcessRequest(req Request) (*http.Response, error) {
tb.mutex.Lock()
defer tb.mutex.Unlock()
if len(tb.Header) != 0 {
netutils.CopyHeaders(req.GetHttpRequest().Header, tb.Header)
}
tb.ProcessedRequests = append(tb.ProcessedRequests, req)
return tb.Response, tb.Error
}
// replyError is a helper function that takes error and replies with HTTP compatible error to the client.
func (p *Proxy) replyError(err error, w http.ResponseWriter, req *http.Request) {
proxyError := convertError(err)
statusCode, body, contentType := p.options.ErrorFormatter.Format(proxyError)
w.Header().Set("Content-Type", contentType)
if proxyError.Headers() != nil {
netutils.CopyHeaders(w.Header(), proxyError.Headers())
}
w.WriteHeader(statusCode)
w.Write(body)
}
func (tb *Recorder) ObserveResponse(req Request, a Attempt) {
tb.mutex.Lock()
defer tb.mutex.Unlock()
if len(tb.Header) != 0 {
netutils.CopyHeaders(req.GetHttpRequest().Header, tb.Header)
}
tb.ProcessedResponses = append(tb.ProcessedResponses, struct {
R Request
A Attempt
}{R: req, A: a})
}
func Post(c *gocheck.C, requestUrl string, header http.Header, body url.Values) (*http.Response, []byte) {
request, _ := http.NewRequest("POST", requestUrl, strings.NewReader(body.Encode()))
netutils.CopyHeaders(request.Header, header)
request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
request.Close = true
response, err := http.DefaultClient.Do(request)
if err != nil {
c.Fatalf("Post: %v", err)
}
bodyBytes, err := ioutil.ReadAll(response.Body)
if err != nil {
c.Fatalf("Post body failed: %v", err)
}
return response, bodyBytes
}
func (l *HttpLocation) copyRequest(req *http.Request, endpoint Endpoint) *http.Request {
outReq := new(http.Request)
*outReq = *req // includes shallow copies of maps, but we handle this below
outReq.URL.Scheme = endpoint.GetUrl().Scheme
outReq.URL.Host = endpoint.GetUrl().Host
outReq.URL.RawQuery = req.URL.RawQuery
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)
netutils.CopyHeaders(outReq.Header, req.Header)
return outReq
}
func Get(c *gocheck.C, requestUrl string, header http.Header, body string) (*http.Response, []byte) {
request, _ := http.NewRequest("GET", requestUrl, strings.NewReader(body))
netutils.CopyHeaders(request.Header, header)
request.Close = true
// the HTTP lib treats Host as a special header. it only respects the value on req.Host, and ignores
// values in req.Headers
if header.Get("Host") != "" {
request.Host = header.Get("Host")
}
response, err := http.DefaultClient.Do(request)
if err != nil {
c.Fatalf("Get: %v", err)
}
bodyBytes, err := ioutil.ReadAll(response.Body)
if err != nil {
c.Fatalf("Get body failed: %v", err)
}
return response, bodyBytes
}
// 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
}
}
// This function alters the original request - adds/removes headers, removes hop headers, changes the request path.
func (l *HttpLocation) rewriteRequest(req *http.Request, endpoint Endpoint) *http.Request {
outReq := new(http.Request)
*outReq = *req // includes shallow copies of maps, but we handle this below
outReq.URL.Scheme = endpoint.GetUrl().Scheme
outReq.URL.Host = endpoint.GetUrl().Host
outReq.URL.RawQuery = req.URL.RawQuery
outReq.Proto = "HTTP/1.1"
outReq.ProtoMajor = 1
outReq.ProtoMinor = 1
outReq.Close = false
outReq.Header = make(http.Header)
netutils.CopyHeaders(outReq.Header, req.Header)
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
if l.options.TrustForwardHeader {
if prior, ok := outReq.Header[headers.XForwardedFor]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
}
outReq.Header.Set(headers.XForwardedFor, clientIP)
}
if req.TLS != nil {
outReq.Header.Set(headers.XForwardedProto, "https")
} else {
outReq.Header.Set(headers.XForwardedProto, "http")
}
if req.Host != "" {
outReq.Header.Set(headers.XForwardedHost, req.Host)
}
outReq.Header.Set(headers.XForwardedServer, l.options.Hostname)
// Remove hop-by-hop headers to the backend. Especially important is "Connection" because we want a persistent
// connection, regardless of what the client sent to us.
netutils.RemoveHeaders(headers.HopHeaders, outReq.Header)
return outReq
}
// Proxy the request to the given upstream, in case if upstream is down
// or failover code sequence has been recorded as the reply, return the error.
// Failover sequence - is a special response code from the upstream that indicates
// that upstream is shutting down and is not willing to accept new requests.
func (p *ReverseProxy) proxyToUpstream(
w http.ResponseWriter,
req *http.Request,
cmd *command.Forward,
upstream *command.Upstream) error {
// Rewrites the request: adds headers, changes urls etc.
outReq := rewriteRequest(req, cmd, upstream)
// Forward the reuest and mirror the response
upstream.Metrics.Requests.Mark(1)
startts := time.Now()
res, err := p.httpTransport.RoundTrip(outReq)
if err != nil {
return err
}
defer res.Body.Close()
upstream.Metrics.Latency.Update(time.Since(startts))
// In some cases upstreams may return special error codes that indicate that instead
// of proxying the response of the upstream to the client we should initiate a failover
if cmd.Failover != nil && len(cmd.Failover.Codes) != 0 {
for _, code := range cmd.Failover.Codes {
if res.StatusCode == code {
upstream.Metrics.Failovers.Mark(1)
glog.Errorf("Upstream %s initiated failover with status code %d", upstream, code)
return fmt.Errorf("Upstream %s initiated failover with status code %d", upstream, code)
}
}
}
netutils.CopyHeaders(w.Header(), res.Header)
w.WriteHeader(res.StatusCode)
upstream.Metrics.Http.MarkResponseCode(res.StatusCode)
io.Copy(w, res.Body)
return nil
}
