如何使用xmlstarlet:将新的子元素<app url="metrics" war="metrics.war"/>添加到下面xml文件中的web元素
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
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<broker xmlns="http://activemq.org/schema">
<jaas-security domain="activemq"/>
<!-- artemis.URI.instance is parsed from artemis.instance by the CLI startup.
This is to avoid situations where you could have spaces or special characters on this URI -->
<server configuration="file:/var/lib/./artemisBroker/etc//broker.xml"/>
<!-- The web server is only bound to localhost by default -->
<web bind="http://0.0.0.0:8161" path="web">
<app url="activemq-branding" war="activemq-branding.war"/>
<app url="artemis-plugin" war="artemis-plugin.war"/>
<app url="console" war="console.war"/>
</web>
</broker>
这是在docker图像中，我提取ActiveMQ并进行设置，然后我想添加一个Prometheus度量插件。我将所需的jar/war文件复制到正确的文件夹中，但现在我需要修改bootstrap.xml以引用war文件。
我可以在Dockerfile中看到，xmlstartlet已被用于修改bind属性，如下所示：
RUN cd /var/lib/artemisBroker/etc &&
xmlstarlet ed -L -N amq="http://activemq.org/schema"
-u "/amq:broker/amq:web/@bind"
-v "http://0.0.0.0:8161" bootstrap.xml
但是我不知道如何添加一个新元素
我发现了这个问题，这有助于澄清一些事情，但我仍然做错了什么
经过一番尝试和错误，我得出了以下结论：
xmlstarlet ed -L -N amq="http://activemq.org/schema"
-s "amq:broker/amq:web"
-t elem -n "app" bootstrap.xml
它似乎运行得很好，并添加了一个<app />元素，但我不知道如何在不覆盖文件中其他<app />元素的情况下添加我想要的属性
我做错了什么？
这样试试：
xmlstarlet ed --subnode "//web" --type elem -n app --insert "// web //app[3]" --type attr --name "url" --value "metrics" --insert "// web //app[3]" --type attr --name "war" --value "metrics.war" bootstrap.xml
看看它是否有效。