How do I redirect back to my form page, with the given POST
params, if my form action throws an exception?
You can use the following:
return Redirect::back()->withInput(Input::all());
If you're using Form Request Validation, this is exactly how Laravel will redirect you back with errors and the given input.
Excerpt from \Illuminate\Foundation\Validation\ValidatesRequests
:
return redirect()->to($this->getRedirectUrl()) ->withInput($request->input()) ->withErrors($errors, $this->errorBag());