重定向asp。net core 2.0 URL小写

我知道这已经有好几个月的历史了,但是对于那些可能正在寻找相同解决方案的人来说,您可以添加一个复杂的重定向实现 IRule 例如:

public class RedirectLowerCaseRule : IRule
{
    public int StatusCode { get; } = (int)HttpStatusCode.MovedPermanently;

    public void ApplyRule(RewriteContext context)
    {
        HttpRequest request = context.HttpContext.Request;
        PathString path = context.HttpContext.Request.Path;
        HostString host = context.HttpContext.Request.Host;

        if (path.HasValue && path.Value.Any(char.IsUpper) || host.HasValue && host.Value.Any(char.IsUpper))
        {
            HttpResponse response = context.HttpContext.Response;
            response.StatusCode = StatusCode;
            response.Headers[HeaderNames.Location] = (request.Scheme + "://" + host.Value + request.PathBase.Value + request.Path.Value).ToLower() + request.QueryString;
            context.Result = RuleResult.EndResponse; 
        }
        else
        {
            context.Result = RuleResult.ContinueRules;
        } 
    }
}

然后可以将其应用于 Startup.cs 在下面 Configure 方法如下:

new RewriteOptions().Add(new RedirectLowerCaseRule());

添加为答案,因为我还不能发表评论。这是对Ben Maxfields答案的补充。

使用他的代码 http://www.example.org/Example/example 不会被重定向,因为 PathBase 未检查大写字母(即使它用于构建新的小写URI)。

所以根据他的代码,我最终使用了这个:

public class RedirectLowerCaseRule : IRule
{
    public int StatusCode { get; } = (int)HttpStatusCode.MovedPermanently;

    public void ApplyRule(RewriteContext context)
    {
        HttpRequest request = context.HttpContext.Request;
        PathString path = context.HttpContext.Request.Path;
        PathString pathbase = context.HttpContext.Request.PathBase;
        HostString host = context.HttpContext.Request.Host;

        if ((path.HasValue && path.Value.Any(char.IsUpper)) || (host.HasValue && host.Value.Any(char.IsUpper)) || (pathbase.HasValue && pathbase.Value.Any(char.IsUpper)))
        {
            Console.WriteLine("Redirect should happen");

            HttpResponse response = context.HttpContext.Response;
            response.StatusCode = StatusCode;
            response.Headers[HeaderNames.Location] = (request.Scheme + "://" + host.Value + request.PathBase + request.Path).ToLower() + request.QueryString;
            context.Result = RuleResult.EndResponse;
        }
        else
        {
            context.Result = RuleResult.ContinueRules;
        }
    }
}

略有不同的实现,也受到 this other thread .

public class RedirectLowerCaseRule : IRule
{
    public void ApplyRule(RewriteContext context)
    {
        HttpRequest request = context.HttpContext.Request;
        string url = request.Scheme + "://" + request.Host + request.PathBase + request.Path;
        bool isGet = request.Method.ToLowerInvariant().Contains("get");

        if ( isGet && url.Contains(".") == false && Regex.IsMatch(url, @"[A-Z]") )
        {
            HttpResponse response = context.HttpContext.Response;
            response.Clear();
            response.StatusCode = StatusCodes.Status301MovedPermanently;
            response.Headers[HeaderNames.Location] = url.ToLowerInvariant() + request.QueryString;
            context.Result = RuleResult.EndResponse;
        }
        else
        {
            context.Result = RuleResult.ContinueRules;
        }
    }
}

我认为有用的更改:
使用 ToLowerInvariant() 而不是 ToLower() (参见可能的问题 here )
保留端口号。
绕过GET以外的请求方法。
假设js/css/images等静态文件应保留大写字母,则使用点绕过请求。
使用 Microsoft.AspNetCore.Http.StatusCodes .

我的两分钱。。。基于 https://github.com/aspnet/AspNetCore/blob/master/src/Middleware/Rewrite/src/RedirectToWwwRule.cs

public class RedirectToLowercaseRule : IRule
{
    private readonly int _statusCode;

    public RedirectToLowercaseRule(int statusCode)
    {
        _statusCode = statusCode;
    }

    public void ApplyRule(RewriteContext context)
    {
        var req = context.HttpContext.Request;

        if (!req.Scheme.Any(char.IsUpper)
            && !req.Host.Value.Any(char.IsUpper)
            && !req.PathBase.Value.Any(char.IsUpper)
            && !req.Path.Value.Any(char.IsUpper))
        {
            context.Result = RuleResult.ContinueRules;
            return;
        }

        var newUrl = UriHelper.BuildAbsolute(req.Scheme.ToLowerInvariant(), new HostString(req.Host.Value.ToLowerInvariant()), req.PathBase.Value.ToLowerInvariant(), req.Path.Value.ToLowerInvariant(), req.QueryString);

        var response = context.HttpContext.Response;
        response.StatusCode = _statusCode;
        response.Headers[HeaderNames.Location] = newUrl;
        context.Result = RuleResult.EndResponse;
        context.Logger.RedirectedToLowercase();
    }
}

使用扩展方法:

public static class RewriteOptionsExtensions
{
    public static RewriteOptions AddRedirectToLowercase(this RewriteOptions options, int statusCode)
    {
        options.Add(new RedirectToLowercaseRule(statusCode));
        return options;
    }

    public static RewriteOptions AddRedirectToLowercase(this RewriteOptions options)
    {
        return AddRedirectToLowercase(options, StatusCodes.Status307TemporaryRedirect);
    }

    public static RewriteOptions AddRedirectToLowercasePermanent(this RewriteOptions options)
    {
        return AddRedirectToLowercase(options, StatusCodes.Status308PermanentRedirect);
    }
}

和日志记录:

internal static class MiddlewareLoggingExtensions
{
    private static readonly Action<ILogger, Exception> _redirectedToLowercase = LoggerMessage.Define(LogLevel.Information, new EventId(1, "RedirectedToLowercase"), "Request redirected to lowercase");

    public static void RedirectedToLowercase(this ILogger logger)
    {
        _redirectedToLowercase(logger, null);
    }
}

和用法:

app.UseRewriter(new RewriteOptions()
    .AddRedirectToLowercase());

其他考虑因素是状态代码的选择。我在扩展方法中使用了307和308,因为它们可以防止请求过程中更改请求方法(例如从GET to POST),但是如果您想允许这种行为,可以使用301和302。看见 What's the difference between HTTP 301 and 308 status codes? 了解更多信息。

确实要重定向吗?如果没有,并且您的目标是在主机和路径中没有大写,那么您可以使用以下IRule。这让我确信,无论我在哪里查看管道中的路径,它都是小写的。

public class RewriteLowerCaseRule : IRule
{
    public void ApplyRule(RewriteContext context)
    {
        var request = context.HttpContext.Request;
        var host = request.Host;
        var pathBase = request.PathBase;
        var path = request.Path;
        if (host.HasValue)
        {
            if (host.Port == null)
            {
                request.Host = new HostString(host.Host.ToLower());
            }
            else
            {
                request.Host = new HostString(host.Host.ToLower(), (int) host.Port);
            }
        }

        if (pathBase.HasValue)
        {
            request.PathBase = new PathString(pathBase.Value.ToLower());
        }

        if (path.HasValue)
        {
            request.Path = new PathString(path.Value.ToLower());
            request.PathBase = new PathString(pathBase.Value.ToLower());
        }

        context.Result = RuleResult.ContinueRules;
    }
}

用法:

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    app.UseRewriter(new RewriteOptions().Add(new RewriteLowerCaseRule()));
    ...
}