Make the parameters nullable

README.md

@@ -87,7 +87,7 @@ $connection->setOauthClient(true);
 
 $connection->setClientId('your-client-id')
     ->setClientSecret('your-client-secret')
-    ->setRedirectUrl('your-callback-url');
+    ->setRedirectUrl('your-callback-url')
     ->setTokenUpdateCallback(function (\Sendy\Api\Connection $connection) {
         $data = [
             'access_token' => $connection->getAccessToken(),

src/Resources/Label.php

@@ -13,15 +13,15 @@ final class Label extends Resource
      * Get a combined PDF with labels of all packages in the given shipments
      *
      * @param non-empty-array<string> $shipmentIds The ids of the shipments
-     * @param 'A4'|'A6' $paperType The paper size to combine the labels on
-     * @param 'top-left'|'top-right'|'bottom-left'|'bottom-right' $startLocation Where to start combining the labels.
-     *                                                                           Used when $paperType is set to A4.
+     * @param null|'A4'|'A6' $paperType The paper size to combine the labels on
+     * @param null|'top-left'|'top-right'|'bottom-left'|'bottom-right' $startLocation Where to start combining the
+     *  labels. Only used when $paperType is set to A4.
      * @return array<string, mixed|array<string|mixed>>
      * @throws GuzzleException
      * @throws ApiException
      * @see https://app.sendy.nl/api/docs#tag/Documents/operation/getLabels
      */
-    public function get(array $shipmentIds, string $paperType = 'A6', string $startLocation = 'top-left'): array
+    public function get(array $shipmentIds, string $paperType = null, string $startLocation = null): array
     {
         $params = [
             'ids' => $shipmentIds,

tests/Resources/LabelTest.php

@@ -24,7 +24,25 @@ public function testGet(): void
         $this->assertEquals([], $resource->get(['123456']));
 
         $this->assertEquals(
-            '/api/labels?ids%5B0%5D=123456&paper_type=A6&start_location=top-left',
+            '/api/labels?ids%5B0%5D=123456',
+            (string) $handler->getLastRequest()->getUri()
+        );
+
+        $this->assertEquals('GET', $handler->getLastRequest()->getMethod());
+    }
+
+    public function testParametersAreSetInURL(): void
+    {
+        $handler = new MockHandler([
+            new Response(200, [], json_encode([])),
+        ]);
+
+        $resource = new Label($this->buildConnectionWithMockHandler($handler));
+
+        $this->assertEquals([], $resource->get(['123456', 'A4', 'top-left']));
+
+        $this->assertEquals(
+            '/api/labels?ids%5B0%5D=123456&ids%5B1%5D=A4&ids%5B2%5D=top-left',
             (string) $handler->getLastRequest()->getUri()
         );