I have to program an application where the users can connect to other websites. For example, the user clicks on the "Amazon" button and the application opens the Amazon website. It then needs to pre-populate the login and password information for the user. (The user added that info to my data base previously.)
My application is in PHP. I have tried using curl to implement this. I can connect, but the cookie is not then used by the users browser. My problem is a lot of websites are protected with tokens and their is a wide variety of different URLs
I have also tried another solution: the application would only fill in the user and password and the user click on "validate" or "login". After researching this, I've found that it may be more difficult. I haven't found any explication about how to fill a form in another website. I think browsers can do it, and I've seen applications such as 'Dashlane' that can do it to, so I think it should be possible.
How do I implement this feature?