Play2.x module for Authentication and Authorization


This module offers Authentication and Authorization features to Play2.x applications

Target

This module targets the Scala version of Play2.x.

Motivation

More secure than Play2.x's Security trait

The existing Security trait in Play2.x API does not define an identifier that identifies a user.

If you use an Email or a userID as an identier, users can not invalidate their session if the session cookie is intercepted.

This module creates a unique SessionID using a secure random number generator. Even if the sessionId cookie is intercepted, users can invalidate the session by logging in again. Your application can expire sessions after a set time limit.

Flexiblity

Since the Security trait in Play2.x API returns Action, complicated action methods wind up deeply nested.

Play2x-Auth provides a way of composition.

Previous Version

for Play2.2.x, Please see previous version 0.11.0 README

for Play2.1.x, Please see previous version 0.10.1 README

for Play2.0.x, Please see previous version 0.7 README

Attention

Since Play2.3's SimpleResult is renamed to Result, The play2.auth trait signatures are changed at version 0.12.0

Since Play2.2's Result is deprecated, The play2.auth trait signatures are changed at version 0.11.0

Installation

Add dependency declarations into your Build.scala or build.sbt file:

• for Play2.3.x

    "jp.t2v" %% "play2-auth"      % "0.13.0",
    "jp.t2v" %% "play2-auth-test" % "0.13.0" % "test"
  

For example your Build.scala might look like this:

  val appDependencies = Seq(
    "jp.t2v" %% "play2-auth"      % "0.13.0",
    "jp.t2v" %% "play2-auth-test" % "0.13.0" % "test"
  )

You don't need to create a play.plugins file.

Usage

1. First create a trait that extends jp.t2v.lab.play2.auth.AuthConfig in app/controllers.

   // Example
   trait AuthConfigImpl extends AuthConfig {
   
     /**
      * A type that is used to identify a user.
      * `String`, `Int`, `Long` and so on.
      */
     type Id = String
   
     /**
      * A type that represents a user in your application.
      * `User`, `Account` and so on.
      */
     type User = Account
   
     /**
      * A type that is defined by every action for authorization.
      * This sample uses the following trait:
      *
      * sealed trait Permission
      * case object Administrator extends Permission
      * case object NormalUser extends Permission
      */
     type Authority = Permission
   
     /**
      * A `ClassTag` is used to retrieve an id from the Cache API.
      * Use something like this:
      */
     val idTag: ClassTag[Id] = classTag[Id]
   
     /**
      * The session timeout in seconds
      */
     val sessionTimeoutInSeconds: Int = 3600
   
     /**
      * A function that returns a `User` object from an `Id`.
      * You can alter the procedure to suit your application.
      */
     def resolveUser(id: Id)(implicit ctx: ExecutionContext): Future[Option[User]] = Account.findById(id)
   
     /**
      * Where to redirect the user after a successful login.
      */
     def loginSucceeded(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] =
       Future.successful(Redirect(routes.Message.main))
   
     /**
      * Where to redirect the user after logging out
      */
     def logoutSucceeded(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] =
       Future.successful(Redirect(routes.Application.login))
   
     /**
      * If the user is not logged in and tries to access a protected resource then redirct them as follows:
      */
     def authenticationFailed(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] =
       Future.successful(Redirect(routes.Application.login))
   
     /**
      * If authorization failed (usually incorrect password) redirect the user as follows:
      */
     def authorizationFailed(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] = 
       Future.successful(Forbidden("no permission"))
   
     /**
      * A function that determines what `Authority` a user has.
      * You should alter this procedure to suit your application.
      */
     def authorize(user: User, authority: Authority)(implicit ctx: ExecutionContext): Future[Boolean] = Future.successful {
       (user.permission, authority) match {
         case (Administrator, _)       => true
         case (NormalUser, NormalUser) => true
         case _                        => false
       }
     }
   
     /**
      * Whether use the secure option or not use it in the cookie.
      * However default is false, I strongly recommend using true in a production.
      */
     override lazy val cookieSecureOption: Boolean = play.api.Play.isProd(play.api.Play.current)
   
     /**
      * Whether a login session is closed when the brower is terminated.
      * default is false.
      */
     override lazy val isTransientCookie: Boolean = false
   
   }

2. Next create a Controller that defines both login and logout actions. This Controller mixes in the jp.t2v.lab.play2.auth.LoginLogout trait and the trait that you created in first step.

   object Application extends Controller with LoginLogout with AuthConfigImpl {
   
     /** Your application's login form.  Alter it to fit your application */
     val loginForm = Form {
       mapping("email" -> email, "password" -> text)(Account.authenticate)(_.map(u => (u.email, "")))
         .verifying("Invalid email or password", result => result.isDefined)
     }
   
     /** Alter the login page action to suit your application. */
     def login = Action { implicit request =>
       Ok(html.login(loginForm))
     }
   
     /**
      * Return the `gotoLogoutSucceeded` method's result in the logout action.
      *
      * Since the `gotoLogoutSucceeded` returns `Future[Result]`,
      * you can add a procedure like the following.
      *
      *   gotoLogoutSucceeded.map(_.flashing(
      *     "success" -> "You've been logged out"
      *   ))
      */
     def logout = Action.async { implicit request =>
       // do something...
       gotoLogoutSucceeded
     }
   
     /**
      * Return the `gotoLoginSucceeded` method's result in the login action.
      *
      * Since the `gotoLoginSucceeded` returns `Future[Result]`,
      * you can add a procedure like the `gotoLogoutSucceeded`.
      */
     def authenticate = Action.async { implicit request =>
       loginForm.bindFromRequest.fold(
         formWithErrors => Future.successful(BadRequest(html.login(formWithErrors))),
         user => gotoLoginSucceeded(user.get.id)
       )
     }
   
   }

3. Lastly, mix jp.t2v.lab.play2.auth.AuthElement trait and the trait that was created in the first step into your Controllers:

   object Message extends Controller with AuthElement with AuthConfigImpl {
   
     // The `StackAction` method
     //    takes `(AuthorityKey, Authority)` as the first argument and
     //    a function signature `RequestWithAttributes[AnyContent] => Result` as the second argument and
     //    returns an `Action`
   
     // thw `loggedIn` method
     //     returns current logged in user
   
     def main = StackAction(AuthorityKey -> NormalUser) { implicit request =>
       val user = loggedIn
       val title = "message main"
       Ok(html.message.main(title))
     }
   
     def list = StackAction(AuthorityKey -> NormalUser) { implicit request =>
       val user = loggedIn
       val title = "all messages"
       Ok(html.message.list(title))
     }
   
     def detail(id: Int) = StackAction(AuthorityKey -> NormalUser) { implicit request =>
       val user = loggedIn
       val title = "messages detail "
       Ok(html.message.detail(title + id))
     }
   
     // Only Administrator can execute this action.
     def write = StackAction(AuthorityKey -> Administrator) { implicit request =>
       val user = loggedIn
       val title = "write message"
       Ok(html.message.write(title))
     }
   
   }

Test

play2.auth provides test module at version 0.8

You can use FakeRequest with logged-in status.

package test

import org.specs2.mutable._

import play.api.test._
import play.api.test.Helpers._
import controllers.{AuthConfigImpl, Messages}
import jp.t2v.lab.play2.auth.test.Helpers._

class ApplicationSpec extends Specification {

  object config extends AuthConfigImpl

  "Messages" should {
    "return list when user is authorized" in new WithApplication {
      val res = Messages.list(FakeRequest().withLoggedIn(config)(1))
      contentType(res) must equalTo("text/html")
    }
  }

}

1. Import jp.t2v.lab.play2.auth.test.Helpers._

2. Define instance what is mixed-in AuthConfigImpl

    object config extends AuthConfigImpl
   

3. Call withLoggedIn method on FakeRequest

   • first argument: AuthConfigImpl instance.
   • second argument: user ID of the user who is logged-in at this request

It makes enable to test controllers with play2.auth

Advanced usage

Changing the authorization depending on the request parameters.

For example, a Social networking application has a function to edit messages.

A user must be able to edit their own messages but not other people's messages.

To achieve this you could define Authority as a Function:

trait AuthConfigImpl extends AuthConfig {

  // Other setup is omitted. 

  type Authority = User => Future[Boolean]

  def authorize(user: User, authority: Authority)(implicit ctx: ExecutionContext): Future[Boolean] = authority(user)

}

object Application extends Controller with AuthElement with AuthConfigImpl {

  private def sameAuthor(messageId: Int)(account: Account): Future[Boolean] =
    Message.getAutherAsync(messageId).map(_ == account)

  def edit(messageId: Int) = StackAction(AuthorityKey -> sameAuthor(messageId)) { implicit request =>
    val user = loggedIn
    val target = Message.findById(messageId)
    Ok(html.message.edit(messageForm.fill(target)))
  }

}

Returning to the originally requested page after login

When an unauthenticated user requests access to page requiring authentication, you first redirect the user to the login page, then, after the user successfully logs in, you redirect the user to the page they originally requested.

To achieve this change authenticationFailed and loginSucceeded:

trait AuthConfigImpl extends AuthConfig {

  // Other settings are omitted.

  def authenticationFailed(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] =
    Future.successful(Redirect(routes.Application.login).withSession("access_uri" -> request.uri))

  def loginSucceeded(request: RequestHeader)(implicit ctx: ExecutionContext): Future[Result] = {
    val uri = request.session.get("access_uri").getOrElse(routes.Message.main.url.toString)
    Future.successful(Redirect(uri).withSession(request.session - "access_uri"))
  }

}

Changing the display depending on whether the user is logged in

If you want to display the application's index differently to non-logged-in users and logged-in users, you can use OptionalAuthElement insted of AuthElement:

object Application extends Controller with OptionalAuthElement with AuthConfigImpl {

  // maybeUser is an instance of `Option[User]`.
  // `OptionalAuthElement` dont need `AuthorityKey`
  def index = StackAction { implicit request =>
    val maybeUser: Option[User] = loggedIn
    val user: User = maybeUser.getOrElse(GuestUser)
    Ok(html.index(user))
  }

}

For action that doesn't require authorization

you can AuthenticationElement insted of AuthElement for authentication without authorization.

object Application extends Controller with AuthenticationElement with AuthConfigImpl {

  def index = StackAction { implicit request =>
    val user: User = loggedIn
    Ok(html.index(user))
  }

}

Return 401 when a request is sent by Ajax

Normally, you want to return a login page redirection at a authentication failed. Although, when the request is sent by Ajax you want to instead return 401, Unauthorized.

You can do it as follows.

def authenticationFailed(request: RequestHeader)(implicit ctx: ExecutionContext) = Future.successful {
  request.headers.get("X-Requested-With") match {
    case Some("XMLHttpRequest") => Unauthorized("Authentication failed")
    case _ => Redirect(routes.Application.login)
  }
}

Action composition

play2.auth use stackable-controller

Suppose you want to validate a token at every action in order to defeat a [Cross Site Request Forgery](https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF) attack.

Since it is impractical to perform the validation in all actions, you would define a trait like this:

import jp.t2v.lab.play2.stackc.{RequestWithAttributes, StackableController}
import scala.concurrent.Future
import play.api.mvc.{Result, Request, Controller}
import play.api.data._
import play.api.data.Forms._

trait TokenValidateElement extends StackableController {
    self: Controller =>

  private val tokenForm = Form("token" -> text)

  private def validateToken(request: Request[_]): Boolean = (for {
    tokenInForm <- tokenForm.bindFromRequest()(request).value
    tokenInSession <- request.session.get("token")
  } yield tokenInForm == tokenInSession).getOrElse(false)

  override def proceed[A](request: RequestWithAttributes[A])(f: RequestWithAttributes[A] => Future[Result]): Future[Result] = {
    if (validateToken(request)) super.proceed(request)(f)
    else Future.successful(BadRequest)
  }

}

You can use TokenValidateElement trait with AuthElement trait.

object Application extends Controller with TokenValidateElement with AuthElement with AuthConfigImpl {

  def page1 = StackAction(AuthorityKey -> NormalUser) { implicit request =>
    // do something
    Ok(html.page1("result"))
  }

  def page2 = StackAction(AuthorityKey -> NormalUser) { implicit request =>
    // do something
    Ok(html.page2("result"))
  }

}

Asynchronous Support

There are asynchronous libraries ( for example: ReactiveMongo, ScalikeJDBC-Async, and so on ).

You should use Future[Result] instead of AsyncResult from Play2.2.

You can use AsyncStack instead of StackAction for Future[Result]

trait HogeController extends AuthElement with AuthConfigImpl {

  def hoge = AsyncStack { implicit req =>
    val messages: Future[Seq[Message]] = AsyncDB.withPool { implicit s => Message.findAll }
    messages.map(Ok(html.view.messages(_)))
  }

}

Stateless vs Stateful implementation.

Play2x-Auth follows the Play framework's stateless policy. However, Play2x-Auth's default implementation is stateful, because the stateless implementation has the following security risk:

If user logs-in to your application in a internet-cafe, then returns home neglecting to logout. If the user logs in again at home they will not invalidate the session.

Nevertheless, you want to use a fully stateless implementation then just override the idContainer method of AuthConfig like this:

trait AuthConfigImpl extends AuthConfig {

  // Other settings omitted.

  override lazy val idContainer: AsyncIdContainer[Id] = AsyncIdContainer(new CookieIdContainer[Id])

}

You could also store the session data in a Relational Database by overriding the id container.

Note: CookieIdContainer doesn't support session timeout.

Running The Sample Application

1. git clone https://github.com/t2v/play2-auth.git
2. cd play2-auth
3. sbt "project sample" run
4. access to http://localhost:9000/ on your browser.

   1. click Apply this script now!

   2. login

      defined accounts

       Email             | Password | Permission
       alice@example.com | secret   | Administrator
       bob@example.com   | secret   | NormalUser
       chris@example.com | secret   | NormalUser
      

Attention -- Distributed Servers

Ehcache, the default cache implementation used by Play2.x, does not work on distributed application servers.

If you have distributed servers, use the Memcached Plugin or something similar.

License

This library is released under the Apache Software License, version 2, which should be included with the source in a file named LICENSE.