From b6d6d5670231cbf64f04f6fcc96ce0ea664f98bc Mon Sep 17 00:00:00 2001
From: Andreas Gohr <andi@splitbrain.org>
Date: Sun, 9 Aug 2026 08:52:25 +0200
Subject: [PATCH] Hand resolved media files to mpdf in both path arguments

mpdf used the resolved local file only when its basepathIsLocal flag was
set. That flag is false whenever the baseurl host differs from the request
host, which a non-default port is enough to cause, since HTTP_HOST carries
the port while the parsed basepath host does not. Media was then fetched
over HTTP again or, for the dw2pdf:// scheme, not at all, leaving exports
without images and without an error message.

Fixes a regression from 3c796bb.
---
 _test/DokuAssetFetcherTest.php | 107 +++++++++++++++++++++++++++++++++
 src/DokuAssetFetcher.php       |  13 +++-
 2 files changed, 119 insertions(+), 1 deletion(-)
 create mode 100644 _test/DokuAssetFetcherTest.php

diff --git a/_test/DokuAssetFetcherTest.php b/_test/DokuAssetFetcherTest.php
new file mode 100644
index 0000000..e6b5436
--- /dev/null
+++ b/_test/DokuAssetFetcherTest.php
@@ -0,0 +1,107 @@
+<?php
+
+namespace dokuwiki\plugin\dw2pdf\test;
+
+use dokuwiki\plugin\dw2pdf\src\Config;
+use dokuwiki\plugin\dw2pdf\src\DokuMpdf;
+use DokuWikiTest;
+use Mpdf\AssetFetcherInterface;
+use Mpdf\Mpdf;
+use ReflectionProperty;
+
+/**
+ * Tests for handing resolved media files over to mpdf.
+ *
+ * @group plugin_dw2pdf
+ * @group plugins
+ */
+class DokuAssetFetcherTest extends DokuWikiTest
+{
+    /**
+     * Get the asset fetcher of a fresh DokuMpdf instance with the given basepath setting.
+     *
+     * Depending on basepathIsLocal mpdf uses either the first or the second argument of
+     * fetchDataFromPath(), so both cases need to be tested. The flag is false on any install
+     * where the baseurl host differs from the request host, a non-default port being enough.
+     *
+     * @param bool $basepathIsLocal Value to force for the mpdf flag
+     * @return AssetFetcherInterface
+     */
+    protected function getFetcher(bool $basepathIsLocal): AssetFetcherInterface
+    {
+        $mpdf = new DokuMpdf(new Config(), 'en');
+        $mpdf->basepathIsLocal = $basepathIsLocal;
+
+        return (new ReflectionProperty(Mpdf::class, 'assetFetcher'))->getValue($mpdf);
+    }
+
+    /**
+     * @return array<string, array{0:string,1:string,2:bool}>
+     */
+    public static function fetchProvider(): array
+    {
+        global $conf;
+
+        $media = DOKU_URL . 'lib/exe/fetch.php?media=wiki:dokuwiki-128.png';
+        $mediaFile = $conf['mediadir'] . '/wiki/dokuwiki-128.png';
+        $static = DOKU_URL . 'lib/images/throbber.gif';
+        $staticFile = DOKU_INC . 'lib/images/throbber.gif';
+
+        return [
+            'fetch url, local basepath' => [$media, $mediaFile, true],
+            'fetch url, remote basepath' => [$media, $mediaFile, false],
+            'static file, local basepath' => [$static, $staticFile, true],
+            'static file, remote basepath' => [$static, $staticFile, false],
+        ];
+    }
+
+    /**
+     * The local file has to be read regardless of the basepath setting.
+     *
+     * The second argument is the unmodified source as mpdf passes it for every image.
+     *
+     * @dataProvider fetchProvider
+     */
+    public function testFetchDataFromPathReadsLocalFile(string $source, string $expected, bool $basepathIsLocal): void
+    {
+        $data = $this->getFetcher($basepathIsLocal)->fetchDataFromPath($source, $source);
+
+        $this->assertSame(file_get_contents($expected), $data);
+    }
+
+    /**
+     * The resolved file has to win over the source mpdf was originally given.
+     *
+     * With a local basepath mpdf prefers the second argument whenever it can open it. For a
+     * media URL that means an anonymous HTTP request back into the wiki instead of our local
+     * copy. A readable file stands in for such a loadable source here.
+     */
+    public function testFetchDataFromPathIgnoresOriginalSource(): void
+    {
+        global $conf;
+        $file = $conf['mediadir'] . '/wiki/dokuwiki-128.png';
+        $source = DOKU_URL . 'lib/exe/fetch.php?media=wiki:dokuwiki-128.png';
+        $loadable = DOKU_INC . 'lib/images/throbber.gif';
+
+        $data = $this->getFetcher(true)->fetchDataFromPath($source, $loadable);
+
+        $this->assertSame(file_get_contents($file), $data);
+    }
+
+    /**
+     * Our pseudo scheme has no stream wrapper, so it can only ever be read locally.
+     *
+     * @testWith [true]
+     *           [false]
+     */
+    public function testFetchDataFromPathReadsDw2pdfScheme(bool $basepathIsLocal): void
+    {
+        global $conf;
+        $file = $conf['mediadir'] . '/wiki/dokuwiki-128.png';
+        $source = 'dw2pdf://' . $file;
+
+        $data = $this->getFetcher($basepathIsLocal)->fetchDataFromPath($source, $source);
+
+        $this->assertSame(file_get_contents($file), $data);
+    }
+}
diff --git a/src/DokuAssetFetcher.php b/src/DokuAssetFetcher.php
index 82d2688..3668ae0 100644
--- a/src/DokuAssetFetcher.php
+++ b/src/DokuAssetFetcher.php
@@ -9,10 +9,21 @@
  */
 class DokuAssetFetcher extends AssetFetcher
 {
+    /**
+     * Load the given asset, preferring a local copy of Dokuwiki media over an HTTP request
+     *
+     * Both arguments are overwritten with the resolved file, because mpdf picks either one
+     * depending on its basepathIsLocal flag. Leaving a URL in one of them would make mpdf
+     * fetch the asset over HTTP again.
+     *
+     * @param string $path Media reference or URL to load
+     * @param string|null $originalSrc The unmodified source as given in the HTML
+     * @return string The asset's binary data, empty when it could not be loaded
+     */
     public function fetchDataFromPath($path, $originalSrc = null)
     {
         $resolved = (new MediaLinkResolver())->resolve($path);
-        if ($resolved) $originalSrc = $resolved['path'];
+        if ($resolved) $path = $originalSrc = $resolved['path'];
         return parent::fetchDataFromPath($path, $originalSrc);
     }
 }