How to receive information?

Question

PHP

I would like to know how to get information from two sites and compare it? More: There are two sites, I need to get information from one and the other site, and compare it, and immediately display it on my site (meaning, people who visit my site do not need to update it, it itself everything calculates and shows new comparisons, in fact, they come in and look - everyone), while the information on donor sites is constantly updated + authorization is required to obtain information. Api is not.

Answer 1

If authorization on sites is quite simple (just a form with a login and password, without captcha and any JS / AJAX bells and whistles), log in once via curl (with cookies and everything that is supposed to), then once a minute, say, read the necessary information, remember themselves in the database (from where to issue it to clients). If an error occurs, try to log in again. If the authorization is fancy (with captcha) - xs, try to manually log in, remember the cookies with the session ID and use them in curl requests. In general, almost everything depends on what kind of authorization is there.

Answer 2

Remove this line:
And copy to freelansim.ru, fl.ru, etc.
This will be the first step in solving such a problem.

Answer 3

In the general case, to parse, they will answer more specifically only if you tell us a little more about the task.

Answer 4

PhantomJS > Png > binary diff

Outputting the result to the client via web sockets.
Something like this.