how to use session in grails

问题:

I am new to grails. And I have to work with session. I have seen the session documentation. But no idea where to put the code in my controller. I have a page for student creation names createStudent. Now I want that this page only be access able when the user will be in session. Now how can I do it. Should I have to set the user in a variable at the time of login. Can anyone please help me on this ?

def index() {
    def user = session["user"]
    if (user){
        redirect(controller: 'admistratorAction', action: 'createUser')
    }else{
        redirect(controller: 'login', action: 'index')
    }

}

回答1:

You could use the session.getAttribute(key) and session.setAttribute(key, value) methods inside your controller. Alternatively, there are plugins such as the Spring Security Core Plugin that already handle this very well.

There's a good tutorial by Peter Ledbrook for the Spring Security plugin here and the plugin documentation links to at least one other tutorial.

** Edit **

As you suggested, in order to use the session directly the user would need to be set in the session at an earlier point. For example:

def setCurrentStudent() {
    def aStudent = [name: "Student1"]
    session["user"] = aStudent
    render "Added $aStudent to the session."
}

Spring Security will do this automatically at login. Then, the current user can then be accessed at any time using the springSecurityService.

class SomeController {
   def springSecurityService
   def someAction = {
       def user = springSecurityService.currentUser
       …
   }
}