refactor redis tests and add asyncRevalidate

Author: donchev7

.github/workflows/main.yml

@@ -21,8 +21,6 @@ jobs:
       # - name: Run linter
       #   run: make lint
       - name: Run unit tests
-        env:
-          REDIS_CONNECTION_STRING: ${{ secrets.REDIS_CONNECTION_STRING }}
         run: |
           go test -race -v -covermode=atomic --coverprofile=coverage.txt ./...
           go test -json ./... > test-report.json

pkg/http/cache.go

@@ -8,9 +8,11 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"net"
 	"net/http"
 	"net/http/httputil"
 	"strings"
+	"time"
 
 	"github.com/rs/zerolog/log"
 
@@ -96,6 +98,43 @@ func newCacheHandler(c Cacher, m MetricsCollector, cfg config.CacheConfig) handl
 	return handler{
 		cacher:           c,
 		metricsCollector: m,
+		cfg:              cfg,
+	}
+}
+
+func (h handler) asyncCacheRevalidate(hashKey string, res http.ResponseWriter, req *http.Request) {
+	ctx := context.Background()
+	newReq := req.WithContext(ctx)
+
+	netTransport := &http.Transport{
+		MaxIdleConnsPerHost: 1000,
+		DisableKeepAlives:   false,
+		IdleConnTimeout:     time.Hour * 1,
+		Dial: (&net.Dialer{
+			Timeout:   10 * time.Second,
+			KeepAlive: 30 * time.Second,
+		}).Dial,
+		TLSHandshakeTimeout:   10 * time.Second,
+		ResponseHeaderTimeout: 10 * time.Second,
+	}
+	client := &http.Client{
+		Timeout:   time.Second * 10,
+		Transport: netTransport,
+	}
+
+	newReq.URL.Host = h.cfg.DownstreamHost.Host
+	newReq.URL.Scheme = h.cfg.DownstreamHost.Scheme
+	newReq.RequestURI = ""
+	resp, err := client.Do(newReq)
+	if err != nil {
+		log.Ctx(ctx).Error().Err(err).Msg("Errored when sending request to the server")
+
+		return
+	}
+	err = h.cacheResponse(ctx, hashKey)(resp)
+
+	if err != nil {
+		log.Print("Error occurred caching response")
 	}
 }
 
@@ -138,7 +177,9 @@ func (h handler) ServeHTTP(res http.ResponseWriter, req *http.Request) {
 	logger.Info().Msg("serving request from memory")
 	h.metricsCollector.CacheHit(req.Method, result.Status)
 
-	// if result.IsStale() => async fetch from downstream
+	if result.IsStale() {
+		go h.asyncCacheRevalidate(hashKey, res, req)
+	}
 	serveResponseFromMemory(res, result)
 }
 

pkg/http/cache_test.go

@@ -65,6 +65,7 @@ func mustURL(t *testing.T, downstreamURL string) *url.URL {
 
 func TestCacheHandler(t *testing.T) {
 	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
 
 	proxied := http.StatusUseProxy
 	endpoint := "/status/200?q=1"

pkg/http/server.go

@@ -32,7 +32,12 @@ func RunServer(opts ServerOpts) {
 
 	mux.HandleFunc("/probes/readiness", readinessHandler(opts.ReadinessChecker))
 
-	server := &h.Server{Addr: fmt.Sprintf("0.0.0.0:%s", opts.Config.ServerConfig.Port), Handler: mux}
+	server := &h.Server{
+		Addr:         fmt.Sprintf("0.0.0.0:%s", opts.Config.ServerConfig.Port),
+		Handler:      mux,
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	}
 	serverCtx, serverStopCtx := context.WithCancel(context.Background())
 
 	log.Info().Msgf("Starting server on port %s", opts.Config.ServerConfig.Port)