php - PHP 防止双重清除 url（改进？）

Question

对于工作中的客户，我们已经建立了一个网站。该网站有一个产品页面，其中可以包含相同类型/构建的变体，因此他们遇到了双重清洁网址的问题。

刚才我写了一个函数，通过在 URL 上附加一个数字来防止这种情况发生。如果 thatclean url 也存在，它会计数。

例如

domain.nl/产品/机器

domain.nl/product/machine-1

domain.nl/product/machine-2

更新！返回 $clean_url; 递归和返回

我编写的函数运行良好，但我想知道我是否采取了正确的方法，是否可以改进。这是代码：

public function prevent_double_cleanurl($cleanurl)
{

    // makes sure it doesnt check against itself
            if($this->ID!=NULL) $and = " AND product_ID <> ".$this->ID;

    $sql = "SELECT product_ID, titel_url FROM " . $this->_table . " WHERE titel_url='".$cleanurl."' " . $and. " LIMIT 1";

    $result = $this->query($sql);

            // if a matching url is found
    if(!empty($result))
    {
        $url_parts = explode("-", $result[0]['titel_url']);
        $last_part = end($url_parts);

        // maximum of 2 digits
        if((int)$last_part && strlen($last_part)<3)
        {
            // if a 1 or 2 digit number is found - add to it
                            array_pop($url_parts);
            $cleanurl = implode("-", $url_parts);

            (int)$last_part++;
        }
        else
        {
            // add a suffix starting at 1
                            $last_part='1';
        }
                    // recursive check
        $cleanurl = $this->prevent_double_cleanurl($cleanurl.'-'.$last_part);
    }

    return $cleanurl; 
}

Answer 1

根据多次使用“clean-url”的可能性，您的方法可能不是最好的。假设从“foo”到“foo-10”，您将调用数据库 10 次。

您似乎也没有清理您推送到 SQL 查询中的数据。你在使用mysql_real_escape_string（或者它的 mysqli，PDO，任何兄弟）？

修改后的代码：

public function prevent_double_cleanurl($cleanurl) {
    $cleanurl_pattern = '#^(?<base>.*?)(-(?<num>\d+))?$#S';

    if (preg_match($cleanurl_pattern, $base, $matches)) {
        $base = $matches['base'];
        $num = $matches['num'] ? $matches['num'] : 0;
    } else {
        $base = $cleanurl;
        $num = 0;
    }

    // makes sure it doesnt check against itself
    if ($this->ID != null) {
        $and = " AND product_ID <> " . $this->ID;
    }

    $sql = "SELECT product_ID, titel_url FROM " . $this->_table . " WHERE titel_url LIKE '" . $base . "-%' LIMIT 1";
    $result = $this->query($sql);

    foreach ($result as $row) {
        if ($this->ID && $row['product_ID'] == $this->ID) {
            // the given cleanurl already has an ID,
            // so we better not touch it
            return $cleanurl;
        }

        if (preg_match($cleanurl_pattern, $row['titel_url'], $matches)) {
            $_base = $matches['base'];
            $_num = $matches['num'] ? $matches['num'] : 0;
        } else {
            $_base = $row['titel_url'];
            $_num = 0;
        }

        if ($base != $_base) {
            // make sure we're not accidentally comparing "foo-123" and "foo-bar-123"
            continue;
        }

        if ($_num > $num) {
            $num = $_num;
        }
    }

    // next free number
    $num++;
    return $base . '-' . $num;
}

我不知道您的干净网址的可能值。上次我做这样的事情时，我的基地可能看起来像some-article-revision-5。这5是实际项目符号的一部分，而不是重复索引。为了区分它们（并允许LIKE过滤掉误报），我使干净的 url 看起来像$base--$num. 双破折号只能出现在基数和重复索引之间，让事情变得更简单......</p>

Answer 2

我没有办法测试这个，所以它在你身上，但我会这样做。我在那里发表了大量评论，解释了我的推理和代码流程。

基本上，不必要的递归将导致比您需要的更多的数据库查询。

<?
public function prevent_double_cleanurl($cleanurl)
{
    $sql = sprintf("SELECT product_ID, titel_url FROM %s WHERE titel_url LIKE '%s%%'", 
        $this->_table, $cleanurl);
    if($this->ID != NULL){ $sql.= sprintf(" AND product_ID <> %d", $this->ID); }

    $results = $this->query($sql);

    $suffix = 0;
    $baseurl = true;
    foreach($results as $row)
    {
        // Consider the case when we get to the "first" row added to the db:
        //  For example: $row['titel_url'] == $cleanurl == 'domain.nl/product/machine'
        if($row['title_url'] == $cleanurl)
        {
            $baseurl = false;   // The $cleanurl is already in the db, "this" is not a base URL
            continue;           // Continue with the next iteration of the foreach loop
        }

        // This could be done using regex, but if this works its fine.
        // Make sure to test for the case when you have both of the following pages in your db:
        //
        //  some-hyphenated-page
        //  some-hyphenated-page-name
        //
        // You don't want the counters to get mixed up
        $url_parts = explode("-", $row['titel_url']);
        $last_part = array_pop($url_parts);
        $cleanrow = implode("-", $url_parts);

        // To get into this block, three things need to be true
        //  1. $last_part must be a numeric string (PHP Duck Typing bleh)
        //  2. When represented as a string, $last_part must not be longer than 2 digits
        //  3. The string passed to this function must match the string resulting from the (n-1) 
        //      leading parts of the result of exploding the table row
        if((is_numeric($last_part)) && (strlen($last_part)<=2) && ($cleanrow == $cleanurl))
        {
            $baseurl = false;                           // If there are records in the database, the 
                                                        //  passed $cleanurl isn't the first, so it 
                                                        //  will need a suffix
            $suffix = max($suffix, (int)$last_part);    // After this foreach loop is done, $suffix 
                                                        //  will contain the highest suffix in the 
                                                        //  database we'll need to add 1 to this to 
                                                        //  get the result url
        }
    }

    // If $baseurl is still true, then we never got into the 3-condition block above, so we never 
    //  a matching record in the database -> return the cleanurl that was passed here, no need
    //  to add a suffix
    if($baseurl)
    {
        return $cleanurl;
    }
    // At least one database record exists, so we need to add a suffix.  The suffix we add will be
    //  the higgest we found in the database plus 1.
    else
    {
        return sprintf("%s-%d", $cleanurl, ($suffix + 1));
    }
}

我的解决方案利用 SQL 通配符 ( %) 将查询数从n减少到 1。

确保您确保我在第 14-20 行中描述的问题案例按预期工作。机器名称（或任何名称）中的连字符可能会做意想不到的事情。

我也用来sprintf格式化查询。确保对作为字符串传递的任何字符串（例如$cleanurl）进行清理。

正如@rodneyrehm 指出的那样，PHP 在它认为是数字字符串方面非常灵活。你可以考虑换掉is_numeric()，ctype_digit()看看它是如何工作的。