How to use cheerio to get the URL of an image on a given page for ALL cases - html

Question

right now I have a function that looks like this:
static getPageImg(url) {
return new Promise((resolve, reject) => {
//get our html
axios.get(url)
.then(resp => {
//html
const html = resp.data;
//load into a $
const $ = cheerio.load(html);
//find ourself a img
const src = url + "/" + $("body").find("img")[0].attribs.src;
//make sure there are no extra slashes
resolve(src.replace(/([^:]\/)\/+/g, "$1"));
})
.catch(err => {
reject(err);
});
});
}
this will handle the average case where the page uses a relative path to link to an image, and the host name is the same as the URL provided.
However,
most of the time the URL scheme will be more complex, like for example the URL might be stackoverflow.com/something/asdasd and what I need is to get stackoverflow.com/someimage link. Or the more interesting case where a CDN is used and the images come from a separate server. For example if I want to link to something from imgur ill give a link like : http://imgur.com/gallery/epqDj. But the actual location of the image is at http://i.imgur.com/pK0thAm.jpg a subdomain of the website. More interesting is the fact that if i was to get the src attribute I would have: "//i.imgur.com/pK0thAm.jpg".
Now I imagine there must be a simple way to get this image, as the browser can very quickly and easily do a "open window in new tab" so I am wondering if anyone knows an easy way to do this other than writing a big function that can handle all these cases.
Thank you!

Answer 1

This is my function that ended up working for all my test cases uysing nodes built in URL type. I had to just use the resolve function.
static getPageImg(url) {
return new Promise((resolve, reject) => {
//get our html
axios.get(url)
.then(resp => {
//html
const html = resp.data;
//load into a $
const $ = cheerio.load(html);
//find ourself a img
const retURL = nodeURL.resolve(url,$("body").find("img")[0].attribs.src);
resolve(retURL);
})
.catch(err => {
reject(err);
});
});
}