From 17e47ab64746c6eb90656278ae75ee5dc87b88dd Mon Sep 17 00:00:00 2001
From: Roman Ackermann <roman-ackermann@bluewin.ch>
Date: Thu, 13 Nov 2025 16:46:22 +0100
Subject: [PATCH 1/3] Added contentType option to Notification

---
 src/Notification.php | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Notification.php b/src/Notification.php
index a924fbb..38f69b0 100644
--- a/src/Notification.php
+++ b/src/Notification.php
@@ -43,6 +43,7 @@ public function getOptions(array $defaultOptions = []): array
         $options['TTL'] = array_key_exists('TTL', $options) ? $options['TTL'] : $defaultOptions['TTL'];
         $options['urgency'] = array_key_exists('urgency', $options) ? $options['urgency'] : $defaultOptions['urgency'];
         $options['topic'] = array_key_exists('topic', $options) ? $options['topic'] : $defaultOptions['topic'];
+        $options['contentType'] = array_key_exists('contentType', $options) ? $options['contentType'] : $defaultOptions['contentType'];
 
         return $options;
     }

From 21955f920cf1ee69ebb4dbc8e6e3b4048ec3561b Mon Sep 17 00:00:00 2001
From: Roman Ackermann <roman-ackermann@bluewin.ch>
Date: Thu, 13 Nov 2025 16:48:00 +0100
Subject: [PATCH 2/3] Added contentType option to WebPush

---
 src/WebPush.php | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/WebPush.php b/src/WebPush.php
index e470b6e..5e37f54 100644
--- a/src/WebPush.php
+++ b/src/WebPush.php
@@ -263,7 +263,7 @@ protected function prepare(array $notifications): array
                 $localPublicKey = $encrypted['localPublicKey'];
 
                 $headers = [
-                    'Content-Type' => 'application/octet-stream',
+                    'Content-Type' => $options['contentType'],
                     'Content-Encoding' => $contentEncoding,
                 ];
 
@@ -384,6 +384,7 @@ public function setDefaultOptions(array $defaultOptions): WebPush
         $this->defaultOptions['topic'] = $defaultOptions['topic'] ?? null;
         $this->defaultOptions['batchSize'] = $defaultOptions['batchSize'] ?? 1000;
         $this->defaultOptions['requestConcurrency'] = $defaultOptions['requestConcurrency'] ?? 100;
+        $this->defaultOptions['contentType'] = $defaultOptions['contentType'] ?? 'application/octet-stream';
 
 
         return $this;

From f0892c1e011f2da12a89da758eaf86c207e5e04e Mon Sep 17 00:00:00 2001
From: Roman Ackermann <roman-ackermann@bluewin.ch>
Date: Thu, 13 Nov 2025 16:49:32 +0100
Subject: [PATCH 3/3] Updated README

---
 README.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/README.md b/README.md
index 978e6b2..c849a1e 100644
--- a/README.md
+++ b/README.md
@@ -202,6 +202,7 @@ $defaultOptions = [
     'urgency' => 'normal', // protocol defaults to "normal". (very-low, low, normal, or high)
     'topic' => 'newEvent', // not defined by default. Max. 32 characters from the URL or filename-safe Base64 characters sets
     'batchSize' => 200, // defaults to 1000
+    'contentType' => 'application/json', // defaults to "application/octet-stream"
 ];
 
 // for every notification
@@ -235,6 +236,11 @@ In order to fix this, WebPush sends notifications in batches. The default size i
 to decrease this number. Do this while instantiating WebPush or calling `setDefaultOptions`. Or, if you want to customize this for a specific flush, give
 it as a parameter : `$webPush->flush($batchSize)`.
 
+#### contentType
+
+Sets the "Content-Type" header for HTTP requests with a non-empty payload sent to the push service. 
+Especially newer [Declarative push messages](https://www.w3.org/TR/push-api/#declarative-push-message) require a specific JSON payload, so this should be set to "application/json" in such cases.
+
 ### Server errors
 
 You can see what the browser vendor's server sends back in case it encountered an error (push subscription expiration, wrong parameters...).