ASP.NET MVC:在不影响性能的情况下路由自定义slug

Question

我想在我的CMS中为页面创建自定义slug,因此用户可以创建自己的SEO-urls(如Wordpress).

我以前通过"滥用"404路由在Ruby on Rails和PHP框架中执行此操作.无法找到请求的控制器时调用此路由,使我能够将用户路由到我的动态页面控制器以解析slug(如果没有找到页面,则从我将其重定向到真实404).这样,仅查询数据库以检查所请求的slug.

但是,在MVC中,仅当路由不适合默认路由时才会调用catch-all路由/{controller}/{action}/{id}.

为了仍然能够解析自定义slugs我修改了RouteConfig.cs文件:

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

        RegisterCustomRoutes(routes);

        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { Controller = "Pages", Action = "Index", id = UrlParameter.Optional }
        );
    }

    public static void RegisterCustomRoutes(RouteCollection routes)
    {
        CMSContext db = new CMSContext();
        List<Page> pages = db.Pages.ToList();
        foreach (Page p in pages)
        {
            routes.MapRoute(
                name: p.Title,
                url: p.Slug,
                defaults: new { Controller = "Pages", Action = "Show", id = p.ID }
            );
        }
        db.Dispose();
    }
}

这解决了我的问题,但要求Pages为每个请求完全查询表.因为重载的show method(public ViewResult Show(Page p))不起作用,我还必须第二次检索页面,因为我只能传递页面ID.

1. 有没有更好的方法来解决我的问题？
2. 是否可以将Page对象传递给我的Show方法而不是页面ID？

Answer 1

即使您的路由注册代码按原样工作，问题也将是路由仅在启动时静态注册。添加新帖子时会发生什么 - 您是否需要重新启动应用程序池？

您可以注册包含 URL 的 SEO slug 部分的路由，然后在查找中使用该 slug。

RouteConfig.cs

routes.MapRoute(
    name: "SeoSlugPageLookup",
    url: "Page/{slug}",
    defaults: new { controller = "Page", 
                    action = "SlugLookup",
                  });

PageController.cs

public ActionResult SlugLookup (string slug)
{
    // TODO: Check for null/empty slug here.

    int? id = GetPageId (slug);

    if (id != null) {    
        return View ("Show", new { id });
    }

    // TODO: The fallback should help the user by searching your site for the slug.
    throw new HttpException (404, "NotFound");
}

private int? GetPageId (string slug)
{
    int? id = GetPageIdFromCache (slug);

    if (id == null) {
        id = GetPageIdFromDatabase (slug);

        if (id != null) {
            SetPageIdInCache (slug, id);
        }
    }

    return id;
}

private int? GetPageIdFromCache (string slug)
{
    // There are many caching techniques for example:
    // http://msdn.microsoft.com/en-us/library/dd287191.aspx
    // http://alandjackson.wordpress.com/2012/04/17/key-based-cache-in-mvc3-5/
    // Depending on how advanced you want your CMS to be,
    // caching could be done in a service layer.
    return slugToPageIdCache.ContainsKey (slug) ? slugToPageIdCache [slug] : null;
}

private int? SetPageIdInCache (string slug, int id)
{
    return slugToPageIdCache.GetOrAdd (slug, id);
}

private int? GetPageIdFromDatabase (string slug)
{
    using (CMSContext db = new CMSContext()) {
        // Assumes unique slugs.
        Page page = db.Pages.Where (p => p.Slug == requestContext.Url).SingleOrDefault ();

        if (page != null) {
            return page.Id;
        }
    }

    return null;
}

public ActionResult Show (int id)
{
    // Your existing implementation.
}

（仅供参考：代码未编译或测试 - 目前还没有可用的开发环境。将其视为伪代码；）

此实现将在每次服务器重新启动时搜索一次 slug。您还可以在启动时预先填充键值 slug-to-id 缓存，这样所有现有的页面查找都会很便宜。