added timeouts to fetch

internal/cache/cache.go

@@ -3,10 +3,12 @@ package cache
 import (
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
 	"sync"
+	"time"
 
 	"golang.org/x/sync/singleflight"
 )
@@ -17,13 +19,25 @@ type Cache struct {
 	mirroredRepos []string
 	sf            singleflight.Group //prevents duplicate downloads
 	mu            sync.Mutex
+	client        http.Client
 }
 
 func NewCache(cacheRoot string, mirrorURL string) *Cache {
+	transport := &http.Transport{
+		DialContext: (&net.Dialer{
+			Timeout: 5 * time.Second,
+		}).DialContext,
+		ResponseHeaderTimeout: 10 * time.Second,
+	}
+
 	return &Cache{
 		cacheRoot:     cacheRoot,
 		mirrorURL:     mirrorURL,
 		mirroredRepos: []string{"core", "extra"},
+		client: http.Client{
+			Timeout:   15 * time.Second,
+			Transport: transport,
+		},
 	}
 }
 
@@ -50,7 +64,7 @@ func (c *Cache) fetch(pkgName string) error {
 	outPkg := filepath.Join(c.cacheRoot, pkgName)
 	pkgURL := c.mirrorURL + pkgName
 
-	resp, err := http.Get(pkgURL)
+	resp, err := c.client.Get(pkgURL)
 	if err != nil {
 		return err
 	}

internal/cache/cache_test.go

@@ -2,12 +2,14 @@ package cache
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"testing"
+	"time"
 )
 
 func newTestServer(t *testing.T, handler http.HandlerFunc) *httptest.Server {
@@ -46,3 +48,61 @@ func TestFetchFileExists(t *testing.T) {
 		t.Errorf("expected file to contain %s got %s", expected, data)
 	}
 }
+
+func TestFetchNotFound(t *testing.T) {
+	svr := newTestServer(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+	}))
+
+	c := newTestCache(t, svr.URL+"/")
+
+	err := c.Fetch("fakefile")
+	var upstreamErr *UpstreamError
+	if !errors.As(err, &upstreamErr) {
+		t.Fatalf("expected UpstreamError fot %v", err)
+	}
+	if upstreamErr.StatusCode != http.StatusNotFound {
+		t.Errorf("expected 404 got %d", upstreamErr.StatusCode)
+	}
+}
+
+func TestFetchSrvError(t *testing.T) {
+	svr := newTestServer(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+	}))
+
+	c := newTestCache(t, svr.URL+"/")
+
+	err := c.Fetch("fakefile")
+	var upstreamErr *UpstreamError
+	if !errors.As(err, &upstreamErr) {
+		t.Fatalf("expected UpstreamError fot %v", err)
+	}
+	if upstreamErr.StatusCode != http.StatusInternalServerError {
+		t.Errorf("expected 500 got %d", upstreamErr.StatusCode)
+	}
+}
+
+func TestFetchSrvDead(t *testing.T) {
+	svr := newTestServer(t, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		select {
+		case <-r.Context().Done():
+			return
+		case <-time.After(60 * time.Second):
+			fmt.Fprint(w, "too late")
+		}
+	}))
+	defer svr.Close()
+
+	c := newTestCache(t, svr.URL+"/")
+
+	err := c.Fetch("fakefile")
+	if err == nil {
+		t.Fatal("expected err got nil")
+	}
+
+	var upstreamErr *UpstreamError
+	if errors.As(err, &upstreamErr) {
+		t.Error("expected network error not UpstreamError")
+	}
+}