Execute Javascript using Selenium or HtmlUnit - selenium

Question

I need small help.
I want to open some page using Java and Selenium or HtmlUnit, and after opening this page execute url like Ajax and get to String the response.
Let say, a want to open http://www.somepage.com , when driver is still on this page, execute GET http://www.somepage.com/myAjax/xyz , which should return JSON.
Then i want to get the JSON response and do something with it.
Could you help me, how to do it ?
Best regards

Answer 1

To inject your own javascript, you can do something like:
new WebConnectionWrapper(webClient) {
public WebResponse getResponse(WebRequest request) throws IOException {
WebResponse response = super.getResponse(request);
if (request.getUrl().toExternalForm().contains("my_url")) {
String content = response.getContentAsString("UTF-8");
// inject the below to the 'content'
String tobeInjected = ""
+ "<script>\n"
+ "var myOwnVariable;\n"
+ "var xmlhttp;\n"
+ "if (window.XMLHttpRequest) {\n"
+ " xmlhttp=new XMLHttpRequest();\n"
+ "}\n"
+ "else {\n"
+ " xmlhttp=new ActiveXObject('Microsoft.XMLHTTP');\n"
+ "}\n"
+ "\n"
+ "xmlhttp.onreadystatechange=function() {\n"
+ " if (xmlhttp.readyState==4 && xmlhttp.status==200) {\n"
+ " myOwnVariable = xmlhttp.responseText;\n"
+ " }\n"
+ "}\n"
+ "\n"
+ "xmlhttp.open('GET', 'http://www.somepage.com/myAjax/xyz', true);\n"
+ "xmlhttp.send();\n"
+ "</script>";
WebResponseData data = new WebResponseData(content.getBytes("UTF-8"),
response.getStatusCode(), response.getStatusMessage(), response.getResponseHeaders());
response = new WebResponse(data, request, response.getLoadTime());
}
return response;
}
};
To retrieve the value of the javascript variable:
webClient.waitForBackgroundJavaScript(5_000);
String value = htmlPage.executeJavaScript("myOwnVariable").toString();