Do not send body/headers to groupcache.

build.sh

@@ -19,7 +19,7 @@ go env -w CGO_ENABLED=1
 
 go test -race ./...
 
-#go test -bench=BenchmarkController ./cmd/gateboard
+#go test -bench=BenchmarkController ./cmd/kubecache
 
 go env -w CGO_ENABLED=0
 

cmd/kubecache/fetch.go

@@ -1,7 +1,6 @@
 package main
 
 import (
- "bytes"
  "context"
  "io"
  "net/http"
@@ -10,24 +9,18 @@ import (
 )
 
 func fetch(c context.Context, client *http.Client, tracer trace.Tracer,
- method, uri string, reqBody []byte, h http.Header) ([]byte, http.Header, int, error) {
+ method, uri string) ([]byte, http.Header, int, error) {
 
  const me = "fetch"
  ctx, span := tracer.Start(c, me)
  defer span.End()
 
- req, errReq := http.NewRequestWithContext(ctx, method, uri,
- bytes.NewBuffer(reqBody))
+ req, errReq := http.NewRequestWithContext(ctx, method, uri, nil)
  if errReq != nil {
  return nil, nil, 500, errReq
  }
 
- // copy headers
- for k, v := range h {
- for _, vv := range v {
- req.Header.Add(k, vv)
- }
- }
+ //req.Header.Add("key", "value")
 
  resp, errDo := client.Do(req)
  if errDo != nil {

cmd/kubecache/groupcache.go

@@ -87,25 +87,13 @@ func startGroupcache(app *application) func() {
  return fmt.Errorf("getter: bad key: '%s'", key)
  }
 
- //
- // retrieve request body/headers from context
- //
- v := ctx.Value(reqKey)
- if v == nil {
- return fmt.Errorf("getter: context key not found: %s", reqKey)
- }
- reqVal, ok := v.(*reqContextValue)
- if !ok {
- return fmt.Errorf("getter: bad context value for key: %s", reqKey)
- }
-
  u, errURL := url.JoinPath(app.cfg.backendURL, uri)
  if errURL != nil {
  return fmt.Errorf("getter: bad URL: %v", errURL)
  }
 
  body, respHeaders, status, errFetch := fetch(ctx, httpClient, app.tracer,
- method, u, reqVal.body, reqVal.header)
+ method, u)
 
  traceID := span.SpanContext().TraceID().String()
  log.Info().Str("traceID", traceID).Msgf("getter: traceID=%s key='%s' url=%s status=%d error:%v",

cmd/kubecache/main.go

@@ -6,7 +6,6 @@ import (
  "encoding/json"
  "flag"
  "fmt"
- "io"
  "os/signal"
  "strconv"
  "syscall"
@@ -231,7 +230,7 @@ func (app *application) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
  key := r.Method + " " + uri
 
- resp, errFetch := app.query(ctx, key, r.Body, r.Header.Clone())
+ resp, errFetch := app.query(ctx, key)
 
  elap := time.Since(begin)
 
@@ -262,32 +261,16 @@ func (app *application) ServeHTTP(w http.ResponseWriter, r *http.Request) {
  }
 }
 
-func (app *application) query(c context.Context, key string, body io.ReadCloser, h http.Header) (response, error) {
+func (app *application) query(c context.Context, key string) (response, error) {
 
  const me = "app.query"
  ctx, span := app.tracer.Start(c, me)
  defer span.End()
 
  var resp response
 
- reqBody, errBody := io.ReadAll(body)
- if errBody != nil {
- log.Error().Msgf("key='%s' body error:%v", key, errBody)
- resp.Status = 500
- return resp, errBody
- }
-
- //
- // create context with request headers/body
- //
- reqVal := reqContextValue{
- header: h,
- body: reqBody,
- }
- ctxReq := context.WithValue(ctx, reqKey, &reqVal)
-
  var data []byte
- errGet := app.cache.Get(ctxReq, key, groupcache.AllocatingByteSliceSink(&data))
+ errGet := app.cache.Get(ctx, key, groupcache.AllocatingByteSliceSink(&data))
 
  if errGet != nil {
  log.Error().Msgf("key='%s' cache error:%v", key, errGet)
@@ -309,12 +292,3 @@ type response struct {
  Status int `json:"status"`
  Header http.Header `json:"header"`
 }
-
-type reqContextKey string
-
-type reqContextValue struct {
- header http.Header
- body []byte
-}
-
-var reqKey = reqContextKey("reqContextKey")