又是我。作为一项技术练习，我尝试使用 WSO2 ESB 代理一些网络流量。具体来说，我正在尝试代理网络流量并即时更改返回的响应，如下所示：
- 让 ESB 接收 HTTP 请求
- 将请求代理到特定服务器
- 收到回复
- 找到任何出现的单词“sad”并将其替换为“happy”（不区分大小写的正则表达式）
- 将更改后的响应传递回浏览器
有人会认为这是一个简单的正则表达式或 XSLT 操作，但事实证明这比我想象的要困难得多。目前，这是我正在使用的代理脚本......
<?xml version="1.0" encoding="UTF-8"?>
<proxy xmlns="http://ws.apache.org/ns/synapse"
name="PassProxy"
transports="https http"
startOnLoad="true"
trace="disable">
<description>Route content from a web server through the ESB service and alter it</description>
<target>
<endpoint>
<address uri="http://server.yoyodyne.com/"/>
</endpoint>
<inSequence/>
<outSequence>
<property name="TheContentIncludingTheSoapEnvelope" expression="."/>
<property xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:ns="http://org.apache.synapse/xsd"
name="TheContentFromSoapBodyButNotReally"
expression="//soapenv:Envelope/soapenv:Body/*"/>
<property name="TheContent"
value="An initial value that should be replaced"
scope="default"
type="STRING"/>
<enrich>
<source type="body" clone="true"/>
<target type="property" property="TheContent"/>
</enrich>
<property name="ContentType" expression="$trp:Content-Type"/>
<property name="ContentLength" expression="$trp:Content-Length"/>
<log level="custom">
<property name="ContentType" expression="$trp:Content-Type"/>
<property name="ContentLength" expression="$trp:Content-Length"/>
<property name="MessageVar" value="TheContent"/>
<property name="TargetMessage" expression="get-property('TheContent')"/>
</log>
<script language="js">
//hack because xpath fn:replace does not work in property tags and fn:translate works on chars not whole strings
var contentType=mc.getProperty('ContentType');
var contentObject=mc.getProperty('TheContent'); //how to get the text of this? And do it in un-escaped format???
if(/text/i.test(contentType)) {
if(!contentObject) {
mc.setProperty('TheAlteredContent','Well that didn\'t work as expected');
} else {
if(typeof contentObject == 'object' || typeof contentObject == 'undefined') {
var returnMessage='';
for (var key in contentObject) {
returnMessage=returnMessage+'found key "'+key+'"\n';
} //end object key for
returnMessage='Can\'t work with this type of input - '+typeof contentObject+'n\Available keys to try:\n'+returnMessage;
contentObject=returnMessage;
} else {
contentObject=contentObject.replaceAll('sad', 'happy');
//more regex statements to go here
} //end typeof if
} //end property check if
} else {
//not text - do nothing
contentObject='binary content (I think). Found content type of "'+contentType+'"';
} //end content type check if
//send the content back
mc.setProperty('TheAlteredContent',contentObject);
</script>
<enrich>
<!-- need to figure out how to replace the content and not append to the end of it. Replace tag on target keeps getting removed for some reason -->
<source type="property" property="TheAlteredContent" clone="true"/>
<target type="body"/>
</enrich>
<!-- doctype headers in the HTML cause logging to fail, so no debugging for you -->
<!--<log level="full"/>-->
<send/>
</outSequence>
</target>
</proxy>
当然，使用丰富的操作可能不是处理这个问题的最佳方式，但在当时这似乎是个好主意。最终发生的是响应的 HTML 部分作为带有转义内容的对象传递到 JS 代码中（或传递出去？？？）。因为“contentObject”var 是一个对象，所以正则表达式失败。使用 toString() 将“contentObject”强制为字符串也不起作用。即使它确实有效，HTML 内容仍然是转义形式，并且转换回可能会出现问题，因为 HTML 代码中可能存在可能需要保持 HTML 格式的转义条目。这里的最后一个问题是“TheAlteredContent”属性的内容被附加到内容而不是替换它，即使属性“action=replace”
任何人都知道如何更好地做到这一点，或者让上述代码工作的方法？