From de0a4f3176adbf65c902d8b01f15ecde9f973618 Mon Sep 17 00:00:00 2001
From: GotPPay <bilal@saburly.com>
Date: Fri, 19 Jan 2018 22:54:50 +0100
Subject: [PATCH] fix reverting skill on failed update

---
 backend/config/constants.js  |  2 +-
 backend/controllers/skill.js | 86 +++++++++++++++++++++++++-----------
 2 files changed, 61 insertions(+), 27 deletions(-)

diff --git a/backend/config/constants.js b/backend/config/constants.js
index c131195..b60f24b 100644
--- a/backend/config/constants.js
+++ b/backend/config/constants.js
@@ -17,7 +17,7 @@ constants.apiResultCodes = {
     AMAZON_FAIL:2, //amazon api doesn't work
     DATABASE_ERROR:3,
     NO_SKILL:4,
-    INCONSISTEN_STATE:5,
+    INCONSISTENT_STATE:5,
 }
 
 constants.HTTPResultCodes = {
diff --git a/backend/controllers/skill.js b/backend/controllers/skill.js
index 6cc36e7..a0c2f5f 100644
--- a/backend/controllers/skill.js
+++ b/backend/controllers/skill.js
@@ -41,6 +41,7 @@ router.put ('/:id', bodyParser.json (), async (req, res, next) => {
         .then (() => {
           //Ok, done, now update skill on Amazon (if needed)
           if (updateOnAmazon) {
+            //We need to update skill on Amazon
             amazonHelper
               .updateSkill (skill)
               .then (amazonResult => {
@@ -51,45 +52,78 @@ router.put ('/:id', bodyParser.json (), async (req, res, next) => {
                   res.json ({result: constants.apiResultCodes.OK, message: ''});
                   alexa.updateModel ();
                 } else {
-                  res.status(constants.HTTPResultCodes.INTERNAL_SERVER_ERROR).json ({
-                    result: constants.apiResultCodes.AMAZON_ERROR,
-                    message: amazonResult,
-                  });
+                  //Update on amazon failed, revert changes in database and send error to user
+                  databaseHelper
+                    .updateSkill (id, currentSkillState)
+                    .then (() => {
+                      res
+                        .status (
+                          constants.HTTPResultCodes.INTERNAL_SERVER_ERROR
+                        )
+                        .json ({
+                          result: constants.apiResultCodes.AMAZON_ERROR,
+                          message: amazonResult,
+                        });
+                    })
+                    .catch (() => {
+                      //This should never happen, something is seriously wrong, like no database connection
+                      res
+                        .status (
+                          constants.HTTPResultCodes.INTERNAL_SERVER_ERROR
+                        )
+                        .json ({
+                          result: constants.apiResultCodes.INCONSISTENT_STATE,
+                          message: '',
+                        });
+                    });
                 }
               })
               .catch (e => {
-                res.status(constants.HTTPResultCodes.INTERNAL_SERVER_ERROR).json ({
-                  result: constants.apiResultCodes.AMAZON_FAIL,
-                  message: e,
-                });
+                //Update on amazon failed, revert changes in database and send error to user
+                databaseHelper
+                  .updateSkill (id, currentSkillState)
+                  .then (() => {
+                    res
+                      .status (constants.HTTPResultCodes.INTERNAL_SERVER_ERROR)
+                      .json ({
+                        result: constants.apiResultCodes.AMAZON_FAIL,
+                        message: e,
+                      });
+                  })
+                  .catch (() => {
+                    //This should never happen, something is seriously wrong, like no database connection
+                    res
+                      .status (constants.HTTPResultCodes.INTERNAL_SERVER_ERROR)
+                      .json ({
+                        result: constants.apiResultCodes.INCONSISTENT_STATE,
+                        message: '',
+                      });
+                  });
               });
-          }else{
+          } else {
+            //No need to update on Amazon, tell to user it's ok
             res.json ({result: constants.apiResultCodes.OK, message: ''});
             alexa.updateModel ();
           }
         })
         .catch (() => {
-          //Update in database didn't go well, revert changes
-          databaseHelper
-            .updateSkill (id, currentSkillState)
-            .then (() => {
-              res.status(constants.HTTPResultCodes.INTERNAL_SERVER_ERROR).json ({
-                result: constants.apiResultCodes.DATABASE_ERROR,
-                message: '',
-              });
-            })
-            .catch (() => {
-              //This should never happen, something is seriously wrong, like no database connection
-              res.status(constants.HTTPResultCodes.INTERNAL_SERVER_ERROR).json ({
-                result: constants.apiResultCodes.INCONSISTEN_STATE,
-                message: '',
-              });
-            });
+          //Update in database didn't go well, no need to revert since it failed to write in the first place
+          //just send error to user
+          res
+          .status (
+            constants.HTTPResultCodes.INTERNAL_SERVER_ERROR
+          )
+          .json ({
+            result: constants.apiResultCodes.DATABASE_ERROR,
+            message: '',
+          });
         });
     })
     .catch (e => {
       //I don't know why, but something went wrong, possibly ID of skill is wrong, doesn't exist in DB
-      res.status(constants.HTTPResultCodes.INTERNAL_SERVER_ERROR).json ({result: constants.apiResultCodes.NO_SKILL, message: ''});
+      res
+        .status (constants.HTTPResultCodes.INTERNAL_SERVER_ERROR)
+        .json ({result: constants.apiResultCodes.NO_SKILL, message: ''});
     });
 });