Give the AuthorizationCode GrantHandler more flow control with flatMap (#90)

* Add sleep in auth code test to show control flow issues

* Added a better test for auth code error handling.

* Switch onSuccess to flatMap for better control flow in AuthorizationCode GrantHandler

Author: billoneil

scala-oauth2-core/src/main/scala/scalaoauth2/provider/GrantHandler.scala

@@ -123,8 +123,10 @@ class AuthorizationCode extends GrantHandler {
       }
 
       val f = issueAccessToken(handler, authInfo)
-      f onSuccess { case _ => handler.deleteAuthCode(code) }
-      f
+      for {
+        accessToken <- f
+        deleteResult <- handler.deleteAuthCode(code)
+      } yield accessToken
     }
   }
 

scala-oauth2-core/src/test/scala/scalaoauth2/provider/AuthorizationCodeSpec.scala

@@ -3,6 +3,7 @@ package scalaoauth2.provider
 import org.scalatest.Matchers._
 import org.scalatest._
 import org.scalatest.concurrent.ScalaFutures
+import org.scalatest.time._
 
 import scala.concurrent.Future
 import scala.concurrent.ExecutionContext.Implicits.global
@@ -22,12 +23,13 @@ class AuthorizationCodeSpec extends FlatSpec with ScalaFutures with OptionValues
       override def createAccessToken(authInfo: AuthInfo[User]): Future[AccessToken] = Future.successful(AccessToken("token1", Some("refreshToken1"), Some("all"), Some(3600), new java.util.Date()))
 
       override def deleteAuthCode(code: String): Future[Unit] = {
+        Thread.sleep(300)
         codeDeleted = true
         Future.successful(Unit)
       }
     })
 
-    whenReady(f) { result =>
+    whenReady(f, timeout(Span(1, Seconds)), interval(Span(50, Millis))) { result =>
       codeDeleted shouldBe true
       result.tokenType shouldBe "Bearer"
       result.accessToken shouldBe "token1"
@@ -57,4 +59,25 @@ class AuthorizationCodeSpec extends FlatSpec with ScalaFutures with OptionValues
       result.scope shouldBe Some("all")
     }
   }
+
+  it should "return a Failure Future" in {
+    val authorizationCode = new AuthorizationCode()
+    val request = new AuthorizationRequest(Map(), Map("client_id" -> Seq("clientId1"), "client_secret" -> Seq("clientSecret1"), "code" -> Seq("code1"), "redirect_uri" -> Seq("http://example.com/")))
+    val f = authorizationCode.handleRequest(request, new MockDataHandler() {
+
+      override def findAuthInfoByCode(code: String): Future[Option[AuthInfo[User]]] = Future.successful(Some(
+        AuthInfo(user = MockUser(10000, "username"), clientId = Some("clientId1"), scope = Some("all"), redirectUri = Some("http://example.com/"))
+      ))
+
+      override def createAccessToken(authInfo: AuthInfo[User]): Future[AccessToken] = Future.successful(AccessToken("token1", Some("refreshToken1"), Some("all"), Some(3600), new java.util.Date()))
+
+      override def deleteAuthCode(code: String): Future[Unit] = {
+        Future.failed(new Exception())
+      }
+    })
+
+    whenReady(f.failed) { e =>
+      e shouldBe a[Exception]
+    }
+  }
 }