PHP XPath 根据'child'值返回父节点

Question

是否可以只运行单个查询来替换多个查询？

//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/@exclude
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/../problem[1]
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/../reference[1]
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/../impact[1]
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/../background[1]
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/../resolution[1]

由于某种原因，这在 PHP 的 xpath(( 函数中不起作用。

//host_info[hostname="localhost" and vulnerability_id="remote_execution"]/(*, ../background, ../impact, ../problem)

我觉得这里必须有更好的方法。 请注意，可以有多个<host_info>节点，这就是我以主机名和vulnerability_id为目标的原因。 但是只有一个<background>，<resolution>节点包含在父节点<vulnerability_id>节点中。

<report>
<vulnerability>
<host_info>
<hostname></hostname>
<vulnerability_id></vulnerability_id>
</host_info>
<host_info>
<hostname></hostname>
<vulnerability_id></vulnerability_id>
</host_info>
<background></background>
<resolution></resolution>
</vulnerability>
<vulnerability>
<host_info></host_info>
<host_info></host_info>
<host_info></host_info>
<host_info></host_info>
<background></background>
<resolution></resolution>
</vulnerability>
</report>

Answer 1

节点列表只有一个维度，因此将多个项目的详细信息序列化为单个列表并不是很有用。

通常，您将使用一个 Xpath 表达式来标识列表节点，然后使用 DOM 方法和相对表达式来获取与这些节点相关的数据：

$document = new DOMDocument();
$document->loadXML($xml);
$xpath = new DOMxpath($document);
foreach ($xpath->evaluate('//host_info[hostname="localhost" and vulnerability_id="remote_execution"]') as $hostInfo) {
var_dump(
[
$hostInfo->getAttribute('exclude'),
$xpath->evaluate('string(parent::*/background)', $hostInfo),
$xpath->evaluate('string(parent::*/resolution)', $hostInfo)
]
);
}

对于单个项目，可以将所有详细信息节点提取到单个结果列表中。但是，像这样的表达式会很快变得复杂，然后您必须添加识别不同细节节点的逻辑。

$document = new DOMDocument();
$document->loadXML($xml);
$xpath = new DOMxpath($document);
$expression = <<<'XPATH'
//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/@exclude|
(//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/parent::*/background)[1]|
(//host_info[hostname="localhost" and vulnerability_id="remote_execution"][1]/parent::*/resolution)[1]
XPATH;
foreach ($xpath->evaluate($expression) as $detail) {
var_dump(
$detail->localName, $detail->textContent
);
}