Many posters have problems debugging their RewriteRule and RewriteCond statements within their .htaccess files. Most of these are using a shared hosting service and therefore don't have access to the root server configuration. They cannot avoid using .htaccess files for rewriting and cannot enable a RewriteLogLevel" as many respondents suggest. Also there are many .htaccess-specific pitfalls and constraints are aren't covered well. Setting up a local test LAMP stack involves too much of a learning curve for most.

所以我的问题是我们建议他们如何自己调试他们的规则。以下是我的一些建议。其他建议将不胜感激。

Understand that the mod_rewrite engine cycles through .htaccess files. The engine runs this loop: do execute server and vhost rewrites (in the Apache Virtual Host Config) find the lowest "Per Dir" .htaccess file on the file path with rewrites enabled if found(.htaccess) execute .htaccess rewrites (in the user's directory) while rewrite occurred So your rules will get executed repeatedly and if you change the URI path then it may end up executing other .htaccessfiles if they exist. So make sure that you terminate this loop, if necessary by adding extra RewriteCond to stop rules firing. Also delete any lower level .htaccess rewrite rulesets unless explicitly intent to use multi-level rulesets. Make sure that the syntax of each Regexp is correct by testing against a set of test patterns to make sure that is a valid syntax and does what you intend with a fully range of test URIs. See answer below for more details. Build up your rules incrementally in a test directory. You can make use of the "execute the deepest .htaccess file on the path feature" to set up a separate test directory (tree) and debug rulesets here without screwing up your main rules and stopping your site working. You have to add them one at a time because this is the only way to localise failures to individual rules. Use a dummy script stub to dump out server and environment variables. (See Listing 2)If your app uses, say, blog/index.php then you can copy this into test/blog/index.php and use it to test out your blog rules in the test subdirectory. You can also use environment variables to make sure that the rewrite engine in interpreting substitution strings correctly, e.g. RewriteRule ^(.*) - [E=TEST0:%{DOCUMENT_ROOT}/blog/html_cache/$1.html] and look for these REDIRECT_* variables in the phpinfo dump. BTW, I used this one and discovered on my site that I had to use %{ENV:DOCUMENT_ROOT_REAL} instead. In the case of redirector looping REDIRECT_REDIRECT_* variables list the previous pass. Etc.. Make sure that you don't get bitten by your browser caching incorrect 301 redirects. See answer below. My thanks to Ulrich Palha for this. The rewrite engine seems sensitive to cascaded rules within an .htaccess context, (that is where a RewriteRule results in a substitution and this falls though to further rules), as I found bugs with internal sub-requests (1), and incorrect PATH_INFO processing which can often be prevents by use of the [NS], [L] and [PT] flags.

还有什么评论或建议吗?

清单1——phpinfo

<?php phpinfo(INFO_ENVIRONMENT|INFO_VARIABLES);

当前回答

最好的调试方法!

在apache的httpd.conf文件中增加LogLevel notice rewrite:trace8,记录所有mod_rewrite的通知。如果你在共享主机上,无法访问httpd.conf,那么就在本地测试并上传到现场。一旦启用这将在很短的时间内生成一个非常大的日志,这意味着它不能在活跃的服务器上进行测试。

其他回答

(类似Doin的想法) 为了显示正在匹配的内容,我使用以下代码

$keys = array_keys($_GET);
foreach($keys as $i=>$key){
    echo "$i => $key <br>";
}

将其保存到服务器根目录下的r.php,然后在.htaccess中进行一些测试 例如,我想匹配不以语言前缀开始的url

RewriteRule ^(?!(en|de)/)(.*)$ /r.php?$1&$2 [L] #$1&$2&...
RewriteRule ^(.*)$ /r.php?nomatch [L] #report nomatch and exit

如果您正在创建重定向,请使用curl进行测试,以避免浏览器缓存问题。 使用-I只获取http头信息。 使用-L跟随所有重定向。

一个是我浪费的几个小时:

如果你已经应用了所有这些技巧,但因为你没有访问服务器错误日志而只出现了500个错误,也许问题不在.htaccess文件中,而在它重定向到的文件中。

在我修复了我的.htaccess问题之后,我又花了两个多小时试图修复它,即使我只是忘记了一些权限。

我把这个留在这里,也许是明显的细节,但让我敲了几个小时的头: 小心使用%{REQUEST_URI},因为@Krist van Besien在他的回答中说的是完全正确的,但不是REQUEST_URI字符串,因为这个TestString的输出以/开头。所以要小心:

RewriteCond %{REQUEST_URI} ^/assets/$  
                            ^
                            | check this pesky fella right here if missing

确保在变量前面使用百分号,而不是美元号。

它是%{HTTP_HOST},不是${HTTP_HOST}。在error_log中什么也没有,也没有内部服务器错误,您的regexp仍然是正确的,规则只是不匹配。如果你经常使用django / genshi模板,并且在肌肉内存中使用${}作为变量替换,这真的很可怕。