mirror of
https://github.com/openfaas/faas.git
synced 2025-06-09 08:46:48 +00:00
131 lines
3.2 KiB
Go
131 lines
3.2 KiB
Go
package handlers
|
|
|
|
import (
|
|
"context"
|
|
"io"
|
|
"log"
|
|
"net/http"
|
|
"strconv"
|
|
"strings"
|
|
"time"
|
|
|
|
"github.com/openfaas/faas/gateway/metrics"
|
|
"github.com/openfaas/faas/gateway/types"
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
)
|
|
|
|
type HTTPNotifier interface {
|
|
Notify(method string, URL string, statusCode int, duration time.Duration)
|
|
}
|
|
|
|
// MakeForwardingProxyHandler create a handler which forwards HTTP requests
|
|
func MakeForwardingProxyHandler(proxy *types.HTTPClientReverseProxy, notifiers []HTTPNotifier) http.HandlerFunc {
|
|
baseURL := proxy.BaseURL.String()
|
|
if strings.HasSuffix(baseURL, "/") {
|
|
baseURL = baseURL[0 : len(baseURL)-1]
|
|
}
|
|
|
|
return func(w http.ResponseWriter, r *http.Request) {
|
|
|
|
requestURL := r.URL.String()
|
|
|
|
start := time.Now()
|
|
|
|
statusCode, err := forwardRequest(w, r, proxy.Client, baseURL, requestURL, proxy.Timeout)
|
|
|
|
seconds := time.Since(start)
|
|
if err != nil {
|
|
log.Printf("error with upstream request to: %s, %s\n", requestURL, err.Error())
|
|
}
|
|
for _, notifier := range notifiers {
|
|
notifier.Notify(r.Method, requestURL, statusCode, seconds)
|
|
}
|
|
}
|
|
}
|
|
|
|
func forwardRequest(w http.ResponseWriter, r *http.Request, proxyClient *http.Client, baseURL string, requestURL string, timeout time.Duration) (int, error) {
|
|
|
|
upstreamReq, _ := http.NewRequest(r.Method, baseURL+requestURL, nil)
|
|
copyHeaders(upstreamReq.Header, &r.Header)
|
|
|
|
upstreamReq.Header["X-Forwarded-For"] = []string{r.RemoteAddr}
|
|
|
|
if r.Body != nil {
|
|
defer r.Body.Close()
|
|
upstreamReq.Body = r.Body
|
|
}
|
|
|
|
ctx, cancel := context.WithTimeout(context.Background(), timeout)
|
|
defer cancel()
|
|
|
|
res, resErr := proxyClient.Do(upstreamReq.WithContext(ctx))
|
|
if resErr != nil {
|
|
badStatus := http.StatusBadGateway
|
|
w.WriteHeader(badStatus)
|
|
return badStatus, resErr
|
|
}
|
|
|
|
if res.Body != nil {
|
|
defer res.Body.Close()
|
|
}
|
|
|
|
copyHeaders(w.Header(), &res.Header)
|
|
|
|
// Write status code
|
|
w.WriteHeader(res.StatusCode)
|
|
|
|
if res.Body != nil {
|
|
// Copy the body over
|
|
io.CopyBuffer(w, res.Body, nil)
|
|
}
|
|
|
|
return res.StatusCode, nil
|
|
}
|
|
|
|
func copyHeaders(destination http.Header, source *http.Header) {
|
|
for k, v := range *source {
|
|
vClone := make([]string, len(v))
|
|
copy(vClone, v)
|
|
(destination)[k] = vClone
|
|
}
|
|
}
|
|
|
|
type PrometheusFunctionNotifier struct {
|
|
Metrics *metrics.MetricOptions
|
|
}
|
|
|
|
func (p PrometheusFunctionNotifier) Notify(method string, URL string, statusCode int, duration time.Duration) {
|
|
seconds := duration.Seconds()
|
|
serviceName := getServiceName(URL)
|
|
|
|
p.Metrics.GatewayFunctionsHistogram.
|
|
WithLabelValues(serviceName).
|
|
Observe(seconds)
|
|
|
|
code := strconv.Itoa(statusCode)
|
|
|
|
p.Metrics.GatewayFunctionInvocation.
|
|
With(prometheus.Labels{"function_name": serviceName, "code": code}).
|
|
Inc()
|
|
}
|
|
|
|
func getServiceName(urlValue string) string {
|
|
var serviceName string
|
|
forward := "/function/"
|
|
if startsWith(urlValue, forward) {
|
|
serviceName = urlValue[len(forward):]
|
|
}
|
|
return serviceName
|
|
}
|
|
|
|
func startsWith(value, token string) bool {
|
|
return len(value) > len(token) && strings.Index(value, token) == 0
|
|
}
|
|
|
|
type LoggingNotifier struct {
|
|
}
|
|
|
|
func (LoggingNotifier) Notify(method string, URL string, statusCode int, duration time.Duration) {
|
|
log.Printf("Forwarded [%s] to %s - [%d] - %f seconds", method, URL, statusCode, duration.Seconds())
|
|
}
|