Thank waldir for answer!
After asking question I perform own research and end with code:
window.onload = function() {
httpRequest = new XMLHttpRequest();
httpRequest.onreadystatechange = function() {
if (httpRequest.readyState !== 4) {
console.log("Not ready, code: %o", httpRequest.readyState);
return;
}
if (httpRequest.status !== 200) {
console.log("Server error: %o", httpRequest.status);
return;
}
var json = JSON.parse(httpRequest.responseText);
console.log("json: %o", json);
var wiki = json.query.pages["1"].revisions[0]["*"];
console.log("wiki: %o", wiki);
var html = InstaView.convert(wiki);
console.log("html: %o", html);
document.getElementById('area').innerHTML = html;
};
var url = 'https://wiki.evil-company.com/api.php?action=query&prop=revisions&format=json&titles=Main_page&rvprop=timestamp|user|comment|content';
httpRequest.open('GET', url, true);
httpRequest.send(null);
}
Here I use https://github.com/cscott/instaview/blob/master/main.js project which is enhanced http://en.wikipedia.org/wiki/User:Pilaf to transform json output to HTML on browser side.
The reason for this code because our wiki is old or misconfigured and action=render is not available. But I trap into cross-domain scripting issue so I think that iframe with action=render is better solution.
See also How do you grab an article including the links in a usable format?
Another suggestion to use action=parse (http://en.wikipedia.org/w/api.php?action=parse&title=Linux) lead to warning:
You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
UPDATE
Perfect solution just append query action=render to any valid wiki URL like:
http://en.wikipedia.org/wiki/Linux?action=render