Saving users database credentials in sessions (user interface for a theme)?

I'm building a UI to configure the settings of a theme (non WP, custom framework) I'm working on. Part of the requirements of that theme is database access.

I would, ideally, like to give the user the option to save his/her database credentials (host, user, pass, name) to be picked up next time the UI is loaded. Is is it safe to save that data in a session on that user's computer?

Or should I look into using fwrite() to create a seperate file, and write that data to it?

The first idea just seems开发者_JS百科 quicker, but I just want to make sure that it's actually safe.

There is no such thing as a "session on the user's computer". What you're referring to are Cookies. There's functions built into PHP for handling those, like setcookie(). Storing credentials in the cookie is never really safe - however, it is a method that's frequently used. When a website offers to 'remember you', they're actually storing a cookie with your username + password, so you can be logged automatically on the next visit.