Upgrade chart rendering support to be composer based

This allow to get rid of manual class loading and have simpler
usage of the library.

Author: PowerKiKi

composer.json

@@ -54,7 +54,8 @@
         "phpunit/phpunit": "^5.7",
         "dompdf/dompdf": "^0.8.0",
         "mpdf/mpdf": "^7.0.0",
-        "friendsofphp/php-cs-fixer": "^2.7"
+        "friendsofphp/php-cs-fixer": "^2.7",
+        "jpgraph/jpgraph": "^4.0"
     },
     "suggest": {
         "ext-gd": "Required for exact column width autocalculation",

composer.lock

@@ -199,6 +199,40 @@ $writer = \PhpOffice\PhpSpreadsheet\IOFactory::createWriter($spreadsheet, 'Pdf')
 $writer = new \PhpOffice\PhpSpreadsheet\Writer\Pdf\Mpdf($spreadsheet);
 ```
 
+### Rendering charts
+
+When rendering charts for HTML or PDF outputs, the process was also simplified. And while
+JpGraph support is still available, it is unfortunately not up to date for latest PHP versions
+and it will generate various warnings.
+
+If you rely on this feature, please consider
+contributing either patches to JpGraph or another `IRenderer` implementation (a good 
+candidate might be [CpChart](https://github.com/szymach/c-pchart)).
+
+Before:
+
+```php
+$rendererName = \PHPExcel_Settings::CHART_RENDERER_JPGRAPH;
+$rendererLibrary = 'jpgraph3.5.0b1/src/';
+$rendererLibraryPath = '/php/libraries/Charts/' . $rendererLibrary;
+
+\PHPExcel_Settings::setChartRenderer($rendererName, $rendererLibraryPath); 
+```
+
+After:
+
+Require the dependency via composer:
+
+```sh
+composer require jpgraph/jpgraph
+```
+
+And then:
+
+```php
+Settings::setChartRenderer(\PhpOffice\PhpSpreadsheet\Chart\Renderer\JpGraph::class);
+```
+
 ### PclZip and ZipArchive
 
 Support for PclZip were dropped in favor of the more complete and modern

docs/topics/migration-from-PHPExcel.md

@@ -6,16 +6,7 @@
 require __DIR__ . '/../Header.php';
 
 //	Change these values to select the Rendering library that you wish to use
-//		and its directory location on your server
-$rendererName = Settings::CHART_RENDERER_JPGRAPH;
-$rendererLibrary = 'jpgraph3.5.0b1/src/';
-$rendererLibraryPath = '/php/libraries/Charts/' . $rendererLibrary;
-
-if (!Settings::setChartRenderer($rendererName, $rendererLibraryPath)) {
-    $helper->log('NOTICE: Please set the $rendererName and $rendererLibraryPath values at the top of this script as appropriate for your directory structure');
-
-    return;
-}
+Settings::setChartRenderer(\PhpOffice\PhpSpreadsheet\Chart\Renderer\JpGraph::class);
 
 $inputFileType = 'Xlsx';
 $inputFileNames = __DIR__ . '/../templates/36write*.xlsx';
@@ -86,7 +77,7 @@
     }
 
     // Save
-    $filename = $helper->getFilename($inputFileName);
+    $filename = $helper->getFilename($inputFileName, 'html');
     $writer = IOFactory::createWriter($spreadsheet, 'Html');
     $writer->setIncludeCharts(true);
     $callStartTime = microtime(true);

samples/Chart/32_Chart_read_write_HTML.php

@@ -8,16 +8,7 @@
 IOFactory::registerWriter('Pdf', \PhpOffice\PhpSpreadsheet\Writer\Pdf\Mpdf::class);
 
 //	Change these values to select the Rendering library that you wish to use
-//		for Chart images, and its directory location on your server
-$rendererName = Settings::CHART_RENDERER_JPGRAPH;
-$rendererLibrary = 'jpgraph3.5.0b1/src/';
-$rendererLibraryPath = '/php/libraries/Charts/' . $rendererLibrary;
-
-if (!Settings::setChartRenderer($rendererName, $rendererLibraryPath)) {
-    $helper->log('NOTICE: Please set the $rendererName and $rendererLibraryPath values at the top of this script as appropriate for your directory structure');
-
-    return;
-}
+Settings::setChartRenderer(\PhpOffice\PhpSpreadsheet\Chart\Renderer\JpGraph::class);
 
 $inputFileType = 'Xlsx';
 $inputFileNames = __DIR__ . '/../templates/36write*.xlsx';
@@ -88,7 +79,7 @@
     }
 
     // Save
-    $filename = $helper->getFilename($inputFileName);
+    $filename = $helper->getFilename($inputFileName, 'pdf');
     $writer = IOFactory::createWriter($spreadsheet, 'Pdf');
     $writer->setIncludeCharts(true);
     $callStartTime = microtime(true);

samples/Chart/32_Chart_read_write_PDF.php

@@ -6,16 +6,7 @@
 require __DIR__ . '/../Header.php';
 
 // Change these values to select the Rendering library that you wish to use
-// and its directory location on your server
-$rendererName = Settings::CHART_RENDERER_JPGRAPH;
-$rendererLibrary = 'jpgraph3.5.0b1/src/';
-$rendererLibraryPath = '/php/libraries/Charts/' . $rendererLibrary;
-
-if (!Settings::setChartRenderer($rendererName, $rendererLibraryPath)) {
-    $helper->log('NOTICE: Please set the $rendererName and $rendererLibraryPath values at the top of this script as appropriate for your directory structure');
-
-    return;
-}
+Settings::setChartRenderer(\PhpOffice\PhpSpreadsheet\Chart\Renderer\JpGraph::class);
 
 $inputFileType = 'Xlsx';
 $inputFileNames = __DIR__ . '/../templates/32readwrite*[0-9].xlsx';
@@ -62,13 +53,14 @@
                 }
                 $helper->log('    ' . $chartName . ' - ' . $caption);
 
-                $jpegFile = $helper->getFilename('35-' . $inputFileNameShort, 'jpg');
+                $jpegFile = $helper->getFilename('35-' . $inputFileNameShort, 'png');
                 if (file_exists($jpegFile)) {
                     unlink($jpegFile);
                 }
 
                 try {
                     $chart->render($jpegFile);
+                    $helper->log('Rendered image: ' . $jpegFile);
                 } catch (Exception $e) {
                     $helper->log('Error rendering chart: ' . $e->getMessage());
                 }

samples/Chart/35_Chart_render.php

@@ -640,28 +640,28 @@ public function refresh()
         }
     }
 
+    /**
+     * Render the chart to given file (or stream).
+     *
+     * @param string $outputDestination Name of the file render to
+     *
+     * @return bool true on success
+     */
     public function render($outputDestination = null)
     {
-        $libraryName = Settings::getChartRendererName();
-        if ($libraryName === null) {
-            return false;
+        if ($outputDestination == 'php://output') {
+            $outputDestination = null;
         }
-        //    Ensure that data series values are up-to-date before we render
-        $this->refresh();
 
-        $libraryPath = Settings::getChartRendererPath();
-        $includePath = str_replace('\\', '/', get_include_path());
-        $rendererPath = str_replace('\\', '/', $libraryPath);
-        if (strpos($rendererPath, $includePath) === false) {
-            set_include_path(get_include_path() . PATH_SEPARATOR . $libraryPath);
+        $libraryName = Settings::getChartRenderer();
+        if ($libraryName === null) {
+            return false;
         }
 
-        $rendererName = '\\PhpOffice\\PhpSpreadsheet\\Chart\\Renderer\\' . $libraryName;
-        $renderer = new $rendererName($this);
+        // Ensure that data series values are up-to-date before we render
+        $this->refresh();
 
-        if ($outputDestination == 'php://output') {
-            $outputDestination = null;
-        }
+        $renderer = new $libraryName($this);
 
         return $renderer->render($outputDestination);
     }

src/PhpSpreadsheet/Chart.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Chart\Renderer;
+
+use PhpOffice\PhpSpreadsheet\Chart;
+
+interface IRenderer
+{
+    /**
+     * IRenderer constructor.
+     *
+     * @param Chart $chart
+     */
+    public function __construct(Chart $chart);
+
+    /**
+     * Render the chart to given file (or stream).
+     *
+     * @param string $filename Name of the file render to
+     *
+     * @return bool true on success
+     */
+    public function render($filename);
+}