WIP Make GD Extension Optional

Fix #3719. Also #367, #469, #1384. It clearly comes up a lot. It has been rejected every time, and maybe it should be rejected now as well. For now, it can't hurt to submit a draft PR and gather feedback. Latest issue makes a decent case for this change, but will it open us up to a series of issues where user fails because GD is not enabled? Based on approximately 30-35 unit tests that fail/error when run without GD, I believe the following is an exhaustive list of what is not supported (because they use functions available only when GD is enabled). Note that function `getimagesize` is available even if GD is not enabled. - reading an image in an Xls file. This is the most likely source of problems if GD is not enabled. - cloning a MemoryDrawing. - creating a MemoryDrawing from string. - setting imageResource for MemoryDrawing. - rendering a chart. - Writer/Xls support for GIF/BMP drawings (Xls requires that these be converted to PNG). - Writer/Xlsx support for GIF/BMP drawings as background images for comments. We convert these to PNG. I am not convinced that these conversions are necessary, and may investigate further if this PR is implemented. - Dompdf and Tcpdf may require GD under certain circumstances. - exact font measurements. I have changed the code so that any attempt to use one of the unsupported functions identified above (except exact font and Dompdf/Tcpdf) will throw an exception ('Required PHP extension GD is not enabled') if they are attempted when GD is not enabled; this will, I hope, make it clear to the end user what the problem is. Dompdf/Tcpdf already generate a similar message when GD is needed but unavailable. For exact fonts, we will just fall back to approximate, which we sometimes do even when GD is available. I will leave this PR in draft status for a while to see if there is feedback pro or con before attempting to merge it.
PHPOffice · Oct 16, 2023 · 49722a0 · 49722a0
1 parent db35a41
commit 49722a0
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Showing 17 changed files with 48 additions and 7 deletions.
diff --git a/composer.json b/composer.json
@@ -69,7 +69,6 @@
         "ext-ctype": "*",
         "ext-dom": "*",
         "ext-fileinfo": "*",
-        "ext-gd": "*",
         "ext-iconv": "*",
         "ext-libxml": "*",
         "ext-mbstring": "*",
@@ -88,6 +87,7 @@
         "voku/anti-xss": "^4.1"
     },
     "require-dev": {
+        "ext-gd": "*",
         "dealerdirect/phpcodesniffer-composer-installer": "dev-main",
         "dompdf/dompdf": "^2.0",
         "friendsofphp/php-cs-fixer": "^3.2",
@@ -101,6 +101,7 @@
         "tecnickcom/tcpdf": "^6.5"
     },
     "suggest": {
+        "ext-gd": "Graphics for images including graphs, and exact font measurement",
         "ext-intl": "PHP Internationalization Functions",
         "mpdf/mpdf": "Option for rendering PDF with PDF Writer",
         "dompdf/dompdf": "Option for rendering PDF with PDF Writer",

diff --git a/samples/Basic/25_In_memory_image.php b/samples/Basic/25_In_memory_image.php
@@ -27,6 +27,7 @@
 
 // Generate an image
 $helper->log('Generate an image');
+MemoryDrawing::checkGd();
 $gdImage = @imagecreatetruecolor(120, 20);
 if (!$gdImage) {
     exit('Cannot Initialize new GD image stream');

diff --git a/samples/Pdf/21_Pdf_TCPDF.php b/samples/Pdf/21_Pdf_TCPDF.php
@@ -17,4 +17,8 @@
 IOFactory::registerWriter('Pdf', $className);
 
 // Save
-$helper->write($spreadsheet, __FILE__, ['Pdf']);
+if (extension_loaded('gd')) {
+    $helper->write($spreadsheet, __FILE__, ['Pdf']);
+} else {
+    $helper->log('Required PHP Extension Gd is not enabled');
+}
diff --git a/samples/Reader/20_Reader_worksheet_hyperlink_image.php b/samples/Reader/20_Reader_worksheet_hyperlink_image.php
@@ -2,11 +2,13 @@
 
 use PhpOffice\PhpSpreadsheet\Shared\File;
 use PhpOffice\PhpSpreadsheet\Spreadsheet;
+use PhpOffice\PhpSpreadsheet\Worksheet\BaseDrawing;
 
 require __DIR__ . '/../Header.php';
 $inputFileType = 'Xlsx';
 
 $helper->log('Start');
+BaseDrawing::checkGd();
 
 $spreadsheet = new Spreadsheet();
 

diff --git a/src/PhpSpreadsheet/Chart/Chart.php b/src/PhpSpreadsheet/Chart/Chart.php
@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheet\Chart;
 
 use PhpOffice\PhpSpreadsheet\Settings;
+use PhpOffice\PhpSpreadsheet\Worksheet\BaseDrawing;
 use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
 
 class Chart
@@ -673,6 +674,7 @@ public function render($outputDestination = null)
 
         /** @var Renderer\IRenderer */
         $renderer = new $libraryName($this);
+        BaseDrawing::checkGd();
 
         return $renderer->render($outputDestination);
     }

diff --git a/src/PhpSpreadsheet/Reader/Xls.php b/src/PhpSpreadsheet/Reader/Xls.php
@@ -1091,6 +1091,7 @@ protected function loadSpreadsheetFromFile(string $filename): Spreadsheet
 
                                 // need check because some blip types are not supported by Escher reader such as EMF
                                 if ($blip = $BSE->getBlip()) {
+                                    MemoryDrawing::checkGd();
                                     $ih = imagecreatefromstring($blip->getData());
                                     if ($ih !== false) {
                                         $drawing = new MemoryDrawing();

diff --git a/src/PhpSpreadsheet/Shared/Font.php b/src/PhpSpreadsheet/Shared/Font.php
@@ -404,7 +404,7 @@ public static function calculateColumnWidth(
         }
 
         // Try to get the exact text width in pixels
-        $approximate = self::$autoSizeMethod === self::AUTOSIZE_METHOD_APPROX;
+        $approximate = (self::$autoSizeMethod === self::AUTOSIZE_METHOD_APPROX) || !extension_loaded('gd');
         $columnWidth = 0;
         if (!$approximate) {
             try {

diff --git a/src/PhpSpreadsheet/Worksheet/BaseDrawing.php b/src/PhpSpreadsheet/Worksheet/BaseDrawing.php
@@ -542,4 +542,18 @@ public function setSrcRect($srcRect): self
 
         return $this;
     }
+
+    private static ?bool $gdEnabled = null;
+
+    public static function checkGd(): void
+    {
+        if (self::$gdEnabled === null) {
+            self::$gdEnabled = extension_loaded('gd');
+        }
+        if (self::$gdEnabled !== true) {
+            // @codeCoverageIgnoreStart
+            throw new PhpSpreadsheetException('Required PHP extension Gd is not enabled');
+            // @codeCoverageIgnoreEnd
+        }
+    }
 }
diff --git a/src/PhpSpreadsheet/Worksheet/MemoryDrawing.php b/src/PhpSpreadsheet/Worksheet/MemoryDrawing.php
@@ -80,6 +80,7 @@ private function cloneResource(): void
         if (!$this->imageResource) {
             return;
         }
+        self::checkGd();
 
         $width = (int) imagesx($this->imageResource);
         $height = (int) imagesy($this->imageResource);
@@ -144,6 +145,7 @@ public static function fromStream($imageStream): self
      */
     public static function fromString(string $imageString): self
     {
+        self::checkGd();
         $gdImage = @imagecreatefromstring($imageString);
         if ($gdImage === false) {
             throw new Exception('Value cannot be converted to an image');
@@ -254,6 +256,7 @@ public function setImageResource(?GdImage $value): static
 
         if ($this->imageResource !== null) {
             // Get width/height
+            self::checkGd();
             $this->width = (int) imagesx($this->imageResource);
             $this->height = (int) imagesy($this->imageResource);
         }

diff --git a/src/PhpSpreadsheet/Writer/Xls.php b/src/PhpSpreadsheet/Writer/Xls.php
@@ -437,6 +437,7 @@ private function processDrawing(BstoreContainer &$bstoreContainer, Drawing $draw
         switch ($imageFormat) {
             case 1: // GIF, not supported by BIFF8, we convert to PNG
                 $blipType = BSE::BLIPTYPE_PNG;
+                BaseDrawing::checkGd();
                 $newImage = @imagecreatefromgif($filename);
                 if ($newImage === false) {
                     throw new Exception("Unable to create image from $filename");
@@ -459,6 +460,7 @@ private function processDrawing(BstoreContainer &$bstoreContainer, Drawing $draw
                 break;
             case 6: // Windows DIB (BMP), we convert to PNG
                 $blipType = BSE::BLIPTYPE_PNG;
+                BaseDrawing::checkGd();
                 $newImage = @imagecreatefrombmp($filename);
                 if ($newImage === false) {
                     throw new Exception("Unable to create image from $filename");

diff --git a/src/PhpSpreadsheet/Writer/Xlsx.php b/src/PhpSpreadsheet/Writer/Xlsx.php
@@ -672,6 +672,7 @@ private function processDrawing(WorksheetDrawing $drawing): string|null|false
         if (!empty($imageData)) {
             switch ($imageData[2]) {
                 case 1: // GIF, not supported by BIFF8, we convert to PNG
+                    BaseDrawing::checkGd();
                     $image = imagecreatefromgif($filename);
                     if ($image !== false) {
                         ob_start();
@@ -693,6 +694,7 @@ private function processDrawing(WorksheetDrawing $drawing): string|null|false
                     break;
 
                 case 6: // Windows DIB (BMP), we convert to PNG
+                    BaseDrawing::checkGd();
                     $image = imagecreatefrombmp($filename);
                     if ($image !== false) {
                         ob_start();

diff --git a/tests/PhpSpreadsheetTests/Functional/DrawingImageHyperlinkTest.php b/tests/PhpSpreadsheetTests/Functional/DrawingImageHyperlinkTest.php
@@ -12,6 +12,7 @@ class DrawingImageHyperlinkTest extends AbstractFunctional
 {
     public function testDrawingImageHyperlinkTest(): void
     {
+        MemoryDrawing::checkGd();
         $gdImage = @imagecreatetruecolor(120, 20);
         $textColor = ($gdImage === false) ? false : imagecolorallocate($gdImage, 255, 255, 255);
         if ($gdImage === false || $textColor === false) {

diff --git a/tests/PhpSpreadsheetTests/Shared/ExactFontTest.php b/tests/PhpSpreadsheetTests/Shared/ExactFontTest.php
@@ -88,6 +88,9 @@ public function testExact(string $fontName, float $excelWidth, float $xmlWidth,
         if ($this->incompleteMessage !== '') {
             self::markTestIncomplete($this->incompleteMessage);
         }
+        if (!extension_loaded('gd')) {
+            self::markTestSkipped('Need GD extension for exact font sizes');
+        }
         $font = new StyleFont();
         $font->setName($fontName);
         $font->setSize(11);
@@ -165,7 +168,7 @@ public function testIssue3626NoPad(): void
         $font = new StyleFont();
         $font->setName($fontName);
         $exactWidth = Font::calculateColumnWidth($font, 'Col3');
-        $expectedWidth = 4.5703;
+        $expectedWidth = extension_loaded('gd') ? 4.5703 : 5.8557;
         if ($exactWidth > 0.95 * $expectedWidth && $exactWidth < 1.05 * $expectedWidth) {
             self::assertTrue(true);
         } else {
@@ -175,7 +178,7 @@ public function testIssue3626NoPad(): void
         $font = new StyleFont();
         $font->setName($fontName);
         $exactWidth = Font::calculateColumnWidth($font, 'Big Column in 4 position');
-        $expectedWidth = 26.2793;
+        $expectedWidth = extension_loaded('gd') ? 26.2793 : 29.4214;
         if ($exactWidth > 0.95 * $expectedWidth && $exactWidth < 1.05 * $expectedWidth) {
             self::assertTrue(true);
         } else {
@@ -198,7 +201,7 @@ public function testIssue3626Pad(): void
         $font->setName($fontName);
         $font->setSize(20);
         $exactWidth = Font::calculateColumnWidth($font, 'Column2');
-        $expectedWidth = 18.8525;
+        $expectedWidth = extension_loaded('gd') ? 18.8525 : 16.7102;
         if ($exactWidth > 0.95 * $expectedWidth && $exactWidth < 1.05 * $expectedWidth) {
             self::assertTrue(true);
         } else {
@@ -218,7 +221,7 @@ public function testIssue3626Pad(): void
         $font = new StyleFont();
         $font->setName($fontName);
         $exactWidth = Font::calculateColumnWidth($font, 'Big Column in 4 position');
-        $expectedWidth = 27.5647;
+        $expectedWidth = extension_loaded('gd') ? 27.5647 : 29.4214;
         if ($exactWidth > 0.95 * $expectedWidth && $exactWidth < 1.05 * $expectedWidth) {
             self::assertTrue(true);
         } else {

diff --git a/tests/PhpSpreadsheetTests/Worksheet/DrawingTest.php b/tests/PhpSpreadsheetTests/Worksheet/DrawingTest.php
@@ -15,6 +15,7 @@ class DrawingTest extends TestCase
 {
     public function testCloningWorksheetWithImages(): void
     {
+        MemoryDrawing::checkGd();
         $gdImage = @imagecreatetruecolor(120, 20);
         $textColor = ($gdImage === false) ? false : imagecolorallocate($gdImage, 255, 255, 255);
         if ($gdImage === false || $textColor === false) {

diff --git a/tests/PhpSpreadsheetTests/Worksheet/MemoryDrawingTest.php b/tests/PhpSpreadsheetTests/Worksheet/MemoryDrawingTest.php
@@ -13,6 +13,7 @@ class MemoryDrawingTest extends TestCase
 {
     public function testMemoryDrawing(): void
     {
+        MemoryDrawing::checkGd();
         $name = 'In-Memory image';
         $gdImage = @imagecreatetruecolor(120, 20);
         if ($gdImage === false) {
@@ -56,6 +57,7 @@ public function testMemoryDrawingFromString(): void
 
     public function testMemoryDrawingFromInvalidString(): void
     {
+        MemoryDrawing::checkGd();
         $this->expectException(Exception::class);
         $this->expectExceptionMessage('Value cannot be converted to an image');
 

diff --git a/tests/PhpSpreadsheetTests/Writer/Html/MemoryDrawingOffsetTest.php b/tests/PhpSpreadsheetTests/Writer/Html/MemoryDrawingOffsetTest.php
@@ -21,6 +21,7 @@ public function testMemoryDrawingOffset(int $w, int $h, int $x, int $y): void
 
         $image = file_get_contents(__DIR__ . '/../../../data/Reader/HTML/memoryDrawingTest.jpg');
         self::assertNotFalse($image, 'unable to read file');
+        MemoryDrawing::checkGd();
         $image = imagecreatefromstring($image);
         self::assertNotFalse($image, 'unable to create image from string');
         $drawing = new MemoryDrawing();

diff --git a/tests/PhpSpreadsheetTests/Writer/Xlsx/DrawingsTest.php b/tests/PhpSpreadsheetTests/Writer/Xlsx/DrawingsTest.php
@@ -565,6 +565,7 @@ public static function providerEditAs(): array
 
     public function testMemoryDrawingDuplicateResource(): void
     {
+        BaseDrawing::checkGd();
         $gdImage = imagecreatetruecolor(120, 20);
         $textColor = ($gdImage === false) ? false : imagecolorallocate($gdImage, 255, 255, 255);
         if ($gdImage === false || $textColor === false) {