feat: add downloadFrom form field

src/DownloadFrom.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Gotenberg;
+
+use JsonSerializable;
+
+class DownloadFrom implements JsonSerializable
+{
+    /** @param array<string,string> $extraHttpHeaders */
+    public function __construct(
+        public readonly string $url,
+        public readonly array|null $extraHttpHeaders = null,
+    ) {
+    }
+
+    /** @return array<string,string|array<string,string>> */
+    public function jsonSerialize(): array
+    {
+        $serialized = [
+            'url' => $this->url,
+        ];
+
+        if (! empty($this->extraHttpHeaders)) {
+            $serialized['extraHttpHeaders'] = $this->extraHttpHeaders;
+        }
+
+        return $serialized;
+    }
+}

src/MultipartFormDataModule.php

@@ -31,6 +31,25 @@ public function outputFilename(string $filename): self
         return $this;
     }
 
+    /**
+     * Sets the URLs to download files from.
+     *
+     * @param DownloadFrom[] $downloadFrom
+     *
+     * @throws NativeFunctionErrored
+     */
+    public function downloadFrom(array $downloadFrom): self
+    {
+        $json = json_encode($downloadFrom);
+        if ($json === false) {
+            throw NativeFunctionErrored::createFromLastPhpError();
+        }
+
+        $this->formValue('downloadFrom', $json);
+
+        return $this;
+    }
+
     /**
      * Sets the callback and error callback that Gotenberg will use to send
      * respectively the output file and the error response.

tests/MultipartFormDataModuleTest.php

@@ -2,6 +2,7 @@
 
 declare(strict_types=1);
 
+use Gotenberg\DownloadFrom;
 use Gotenberg\Exceptions\NativeFunctionErrored;
 use Gotenberg\Test\DummyMultipartFormDataModule;
 
@@ -11,6 +12,10 @@ function (): void {
         $dummy   = new DummyMultipartFormDataModule('https://my.url/');
         $request = $dummy
             ->outputFilename('my_filename')
+            ->downloadFrom([
+                new DownloadFrom('https://my.url/my_filename'),
+                new DownloadFrom('https://my.url/my_filename_2', ['X-Header' => 'value']),
+            ])
             ->webhook('https://my.webhook.url', 'https://my.webhook.error.url')
             ->webhookMethod('POST')
             ->webhookErrorMethod('PUT')
@@ -21,6 +26,9 @@ function (): void {
             ->build();
 
         expect($request->getHeader('Gotenberg-Output-Filename'))->toMatchArray(['my_filename']);
+
+        expect(sanitize($request->getBody()->getContents()))->toContainFormValue('downloadFrom', '[{"url":"https:\/\/my.url\/my_filename"},{"url":"https:\/\/my.url\/my_filename_2","extraHttpHeaders":{"X-Header":"value"}}]');
+
         expect($request->getHeader('Gotenberg-Webhook-Url'))->toMatchArray(['https://my.webhook.url']);
         expect($request->getHeader('Gotenberg-Webhook-Error-Url'))->toMatchArray(['https://my.webhook.error.url']);
         expect($request->getHeader('Gotenberg-Webhook-Method'))->toMatchArray(['POST']);