Remove application/graphql as a content type header

Author: lizkenyon

CHANGELOG.md

@@ -7,6 +7,8 @@ and adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
 
+- [#379](https://github.com/Shopify/shopify-api-php/pull/379) [Patch] Fix GraphQL `Content-Type` header to be `application/json`
+
 ## v5.7.0 - 2024-10-22
 - [#371](https://github.com/Shopify/shopify-api-php/pull/371) [Minor] Remove API version validation to allow more flexibility of API version. And add support for 2024-10 API version
 - [#370](https://github.com/Shopify/shopify-api-php/pull/370) [Patch] Fix params set to zero being removed from request payload

src/Clients/Graphql.php

@@ -60,10 +60,7 @@ public function query(
         $extraHeaders[$accessTokenHeader] = $accessToken;
 
         if (is_array($data)) {
-            $dataType = Http::DATA_TYPE_JSON;
             $data = json_encode($data);
-        } else {
-            $dataType = Http::DATA_TYPE_GRAPHQL;
         }
 
         return $this->client->post(
@@ -72,7 +69,6 @@ public function query(
             $extraHeaders,
             $query,
             $tries,
-            $dataType,
         );
     }
 

src/Clients/Http.php

@@ -20,7 +20,6 @@ class Http
     public const METHOD_DELETE = 'DELETE';
 
     public const DATA_TYPE_JSON = 'application/json';
-    public const DATA_TYPE_GRAPHQL = 'application/graphql';
 
     private const RETRIABLE_STATUS_CODES = [429, 500];
     private const DEPRECATION_ALERT_SECONDS = 3600;

tests/Clients/GraphqlTest.php

@@ -101,7 +101,7 @@ public function testCanQueryWithDataString()
                 'POST',
                 "Shopify Admin API Library for PHP v$this->version",
                 [
-                    'Content-Type: application/graphql',
+                    'Content-Type: application/json',
                     'Content-Length: ' . strlen($this->testQueryString),
                     'X-Shopify-Access-Token: token'
                 ],
@@ -182,7 +182,7 @@ public function testCanQueryWithExtraHeaders()
                 'POST',
                 "Shopify Admin API Library for PHP v$this->version",
                 [
-                    'Content-Type: application/graphql',
+                    'Content-Type: application/json',
                     'Content-Length: ' . strlen($this->testQueryString),
                     'Extra-Extra: hear_all_about_it',
                     'X-Shopify-Access-Token: token'

tests/Clients/StorefrontTest.php

@@ -38,7 +38,7 @@ public function testCanMakeRequest()
                 'POST',
                 null,
                 [
-                    'Content-Type: application/graphql',
+                    'Content-Type: application/json',
                     'X-Shopify-Storefront-Access-Token: test_token',
                 ],
                 $this->query,
@@ -65,7 +65,7 @@ public function testCanMakeRequestForPrivateApp()
                 'POST',
                 null,
                 [
-                    'Content-Type: application/graphql',
+                    'Content-Type: application/json',
                     'X-Shopify-Storefront-Access-Token: private_token',
                 ],
                 $this->query,
@@ -91,7 +91,7 @@ public function testCanUseTokenForPrivateAppRequest()
                 'POST',
                 null,
                 [
-                    'Content-Type: application/graphql',
+                    'Content-Type: application/json',
                     'X-Shopify-Storefront-Access-Token: test_token',
                 ],
                 $this->query,