From d95cbc0627ed6af880721f997f0ab640f91ea2d7 Mon Sep 17 00:00:00 2001
From: Matt Lott <mattlott@live.com>
Date: Wed, 7 Oct 2015 15:14:26 -0700
Subject: [PATCH] Course instance redeem API returns 200 for double redeem

If a user has already redeemed course prepaid code, return 200 and the
related course instances.  Simplifies client-side experience.
---
 server/courses/course_instance_handler.coffee |  3 ++
 .../functional/course_instance.spec.coffee    | 30 +++++++++++++++++--
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/server/courses/course_instance_handler.coffee b/server/courses/course_instance_handler.coffee
index 25abed4c8..a6e50509a 100644
--- a/server/courses/course_instance_handler.coffee
+++ b/server/courses/course_instance_handler.coffee
@@ -142,6 +142,9 @@ CourseInstanceHandler = class CourseInstanceHandler extends Handler
         return @sendDatabaseError(res, err) if err
         return @sendForbiddenError(res) if prepaid.get('redeemers')?.length >= prepaid.get('maxRedeemers')
 
+        if _.find((prepaid.get('redeemers') ? []), (a) -> a.userID.equals(req.user.id))
+          return @sendSuccess(res, courseInstances)
+
         # Add to prepaid redeemers
         query =
           _id: prepaid.get('_id')
diff --git a/test/server/functional/course_instance.spec.coffee b/test/server/functional/course_instance.spec.coffee
index 5084f48c5..ff6506a01 100644
--- a/test/server/functional/course_instance.spec.coffee
+++ b/test/server/functional/course_instance.spec.coffee
@@ -222,7 +222,7 @@ describe 'CourseInstance', ->
 
   describe 'Redeem prepaid code', ->
 
-    it 'Redeem prepaid code an instance of max 2', (done) ->
+    it 'Redeem prepaid code for an instance of max 2', (done) ->
       stripe.tokens.create {
         card: { number: '4242424242424242', exp_month: 12, exp_year: 2020, cvc: '123' }
       }, (err, token) ->
@@ -264,7 +264,7 @@ describe 'CourseInstance', ->
                         expect(usersFound).toEqual(2)
                         done()
 
-    it 'Redeem full prepaid code on instance of max 1', (done) ->
+    it 'Redeem full prepaid code for on instance of max 1', (done) ->
       stripe.tokens.create {
         card: { number: '4242424242424242', exp_month: 12, exp_year: 2020, cvc: '123' }
       }, (err, token) ->
@@ -326,3 +326,29 @@ describe 'CourseInstance', ->
                     return done(err) if err
                     expect(prepaid.get('redeemers')?.length).toEqual(prepaid.get('maxRedeemers'))
                     done()
+
+    it 'Redeem prepaid code twice', (done) ->
+      stripe.tokens.create {
+        card: { number: '4242424242424242', exp_month: 12, exp_year: 2020, cvc: '123' }
+      }, (err, token) ->
+        loginNewUser (user1) ->
+          createCourse 0, (err, course) ->
+            expect(err).toBeNull()
+            return done(err) if err
+            createCourseInstances user1, course.get('_id'), 2, token.id, (err, courseInstances) ->
+              expect(err).toBeNull()
+              return done(err) if err
+              expect(courseInstances.length).toEqual(1)
+              Prepaid.findById courseInstances[0].get('prepaidID'), (err, prepaid) ->
+                expect(err).toBeNull()
+                return done(err) if err
+                loginNewUser (user2) ->
+                  # Redeem once
+                  request.post {uri: courseInstanceRedeemURL, json: {prepaidCode: prepaid.get('code')} }, (err, res) ->
+                    expect(err).toBeNull()
+                    expect(res.statusCode).toBe(200)
+                    # Redeem twice
+                    request.post {uri: courseInstanceRedeemURL, json: {prepaidCode: prepaid.get('code')} }, (err, res) ->
+                      expect(err).toBeNull()
+                      expect(res.statusCode).toBe(200)
+                      done()