autoresearch iter 35: BUGFIX a failed whitelist read is no longer cached as an admin decision

backend/plugins/domain/upload/cache/access_cache_retry_test.go

@@ -0,0 +1,56 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package cache
+
+import (
+	"Wavelet/plugins/domain/upload/shared"
+	"context"
+	"testing"
+)
+
+// configRow mirrors just enough of w_system_configs to rebuild it mid-test.
+type configRow struct {
+	Key   string `gorm:"primaryKey;size:64"`
+	Value string `gorm:"type:text;not null"`
+	Type  string `gorm:"size:32;not null"`
+}
+
+// TableName returns the system config table.
+func (configRow) TableName() string { return "w_system_configs" }
+
+// TestWhitelistReadFailureIsNotCachedAsConfigured pins the defect where a failed
+// read of the public access whitelist was discarded and the resulting restricted
+// default was then cached as though the admin had configured it, narrowing access
+// for the whole TTL with nothing to retry it sooner.
+func TestWhitelistReadFailureIsNotCachedAsConfigured(t *testing.T) {
+	db, cleanup := shared.SetupTestEnv(t)
+	defer cleanup()
+	ResetAccessCaches()
+	t.Cleanup(ResetAccessCaches)
+
+	ctx := context.Background()
+
+	// Make the config unreadable, then take one sample through the failure path.
+	if err := db.Exec("DROP TABLE w_system_configs").Error; err != nil {
+		t.Fatalf("drop config table: %v", err)
+	}
+	if IsFilePublic(ctx, "document") {
+		t.Fatal(`document reported public while the whitelist cannot be read`)
+	}
+
+	// Restore a configured whitelist that includes document.
+	if err := db.AutoMigrate(&configRow{}); err != nil {
+		t.Fatalf("recreate config table: %v", err)
+	}
+	row := configRow{Key: "file_access_whitelist", Value: `["avatar","document"]`, Type: "system"}
+	if err := db.Create(&row).Error; err != nil {
+		t.Fatalf("seed whitelist: %v", err)
+	}
+
+	// A failed first read must not have been cached as a real answer, so this call
+	// has to re-read and see the configured list.
+	if !IsFilePublic(ctx, "document") {
+		t.Error("whitelist stayed pinned to the default after a read failure; the failed lookup must be retried")
+	}
+}