perf(appstore): reduce resource requests during synchronization

core/init/proxy/app_icon_test.go

@@ -0,0 +1,34 @@
+package proxy
+
+import (
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+type iconRedirectTransport func(*http.Request) (*http.Response, error)
+
+func (f iconRedirectTransport) RoundTrip(req *http.Request) (*http.Response, error) { return f(req) }
+
+func TestLocalAppIconRedirectIsPassedToBrowser(t *testing.T) {
+	const icon = "https://cdn.example/icon.png?signature=a%2Bb&v=42"
+	calls := 0
+	proxy := newLocalAgentProxy(iconRedirectTransport(func(req *http.Request) (*http.Response, error) {
+		calls++
+		if req.URL.Host != "unix" || req.URL.Path != "/api/v2/apps/icon/php" {
+			t.Fatalf("proxy attempted to fetch a remote image: %s", req.URL)
+		}
+		return &http.Response{
+			StatusCode: http.StatusFound,
+			Header:     http.Header{"Location": {icon}, "Cache-Control": {"no-cache"}},
+			Body:       io.NopCloser(strings.NewReader("")),
+		}, nil
+	}))
+	rw := httptest.NewRecorder()
+	proxy.ServeHTTP(rw, httptest.NewRequest(http.MethodGet, "/api/v2/apps/icon/php", nil))
+	if rw.Code != http.StatusFound || rw.Header().Get("Location") != icon || rw.Header().Get("Cache-Control") != "no-cache" || calls != 1 {
+		t.Fatalf("local proxy did not preserve the redirect: status=%d headers=%v calls=%d", rw.Code, rw.Header(), calls)
+	}
+}