From 03964cd8c8882ca092a724b2920578e284a26fb2 Mon Sep 17 00:00:00 2001
From: Valentin Trimaille <valentin.t@apple.com>
Date: Mon, 11 Nov 2019 19:23:01 +0100
Subject: [PATCH 1/3] Limited 'message' event listener to execute only once.
 Handled response '204 NO CONTENT' from Spotify API

---
 public/spotify-player.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/public/spotify-player.js b/public/spotify-player.js
index 4ccfdfa..1c0453d 100644
--- a/public/spotify-player.js
+++ b/public/spotify-player.js
@@ -96,6 +96,11 @@ class SpotifyPlayer {
 
       const width = 450, height = 730, left = screen.width / 2 - width / 2, top = screen.height / 2 - height / 2;
 
+      const eventOptions = {
+        once: true,
+        capture: false
+      };
+
       window.addEventListener(
         'message',
         event => {
@@ -113,7 +118,7 @@ class SpotifyPlayer {
             }
           }
         },
-        false
+        eventOptions
       );
 
       const w = window.open(
@@ -157,6 +162,9 @@ class SpotifyPlayer {
         // assume an error on Spotify's site
         console.error('Got error when fetching player', response);
         return null;
+      } else if (response.status === 204) {
+        // No song playing, or account in private mode
+        return Promise.resolve(null);
       } else {
         return response.json();
       }

From 1b6e490b7ebc7978aa28459ff92c5e970086ab05 Mon Sep 17 00:00:00 2001
From: Valentin Trimaille <valentin.t@apple.com>
Date: Mon, 11 Nov 2019 20:14:58 +0100
Subject: [PATCH 2/3] Removed handling of '204 NO CONTENT' response, for pull
 request.

---
 public/spotify-player.js | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/public/spotify-player.js b/public/spotify-player.js
index 1c0453d..3b237ba 100644
--- a/public/spotify-player.js
+++ b/public/spotify-player.js
@@ -162,9 +162,6 @@ class SpotifyPlayer {
         // assume an error on Spotify's site
         console.error('Got error when fetching player', response);
         return null;
-      } else if (response.status === 204) {
-        // No song playing, or account in private mode
-        return Promise.resolve(null);
       } else {
         return response.json();
       }

From b3123920739357b2970844855f4e2ca8003cf4ca Mon Sep 17 00:00:00 2001
From: Valentin Trimaille <valentin.t@apple.com>
Date: Mon, 11 Nov 2019 20:43:00 +0100
Subject: [PATCH 3/3] Handled reponse '204 NO CONTENT' from Spotify API. Change
 in client code necessary as shown in https://codepen.io/montspy/pen/KKKBGpP

---
 public/spotify-player.js | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/public/spotify-player.js b/public/spotify-player.js
index 4ccfdfa..d1ed4d0 100644
--- a/public/spotify-player.js
+++ b/public/spotify-player.js
@@ -58,9 +58,7 @@ class SpotifyPlayer {
         if (!this.obtainingToken) {
           this.fetchPlayer()
             .then(data => {
-              if (data !== null && data.item !== null) {
-                this.dispatch('update', data);
-              }
+              this.dispatch('update', data);
             })
             .catch(e => {
               console.log('Logging user out due to error', e);
@@ -157,6 +155,17 @@ class SpotifyPlayer {
         // assume an error on Spotify's site
         console.error('Got error when fetching player', response);
         return null;
+      } else if (response.status === 204) {
+        // No song playing, or account in private mode
+        return response.json()
+        .then(json => {
+          // Account in private mode, json = {}
+          return Promise.resolve(json);
+        })
+        .catch(err => {
+          // No song playing, empty response
+          return Promise.resolve(null);
+        });
       } else {
         return response.json();
       }