add transformation exception (#23)

* add transformation exception, with previous errors based on libxml errors * reset error level to previous state, instead of leaving it to true * style
genkgo · May 5, 2019 · 3ffa879 · 3ffa879
1 parent 70d40a6
commit 3ffa879
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Showing 4 changed files with 109 additions and 17 deletions.
diff --git a/src/Exception/TransformationException.php b/src/Exception/TransformationException.php
@@ -0,0 +1,28 @@
+<?php
+declare(strict_types=1);
+
+namespace Genkgo\Xsl\Exception;
+
+final class TransformationException extends \Exception
+{
+    public static function fromLibxmlErrorList(array $errors): self
+    {
+        if ($errors === []) {
+            throw new \InvalidArgumentException('Cannot create exception while there are no libxml errors');
+        }
+
+        $exceptions = [];
+        while ($errors !== []) {
+            /** @var \LibXMLError $error */
+            $error = \array_shift($errors);
+            $previous = isset($exceptions[0]) ? $exceptions[0] : null;
+            $exception = new self($error->message, 0, $previous);
+            $exception->file = $error->file;
+            $exception->code = $error->code;
+            $exception->line = $error->line;
+            $exceptions[] = $exception;
+        }
+
+        return new self('Transformation failed: ' . $exceptions[0]->message, 0, $exceptions[0]);
+    }
+}
diff --git a/src/XsltProcessor.php b/src/XsltProcessor.php
@@ -6,6 +6,7 @@
 use DOMDocument;
 use Genkgo\Xsl\Callback\FunctionCollection;
 use Genkgo\Xsl\Callback\PhpCallback;
+use Genkgo\Xsl\Exception\TransformationException;
 use Genkgo\Xsl\Util\TransformerCollection;
 use Psr\SimpleCache\CacheInterface;
 use SimpleXMLElement;
@@ -65,12 +66,19 @@ public function transformToXML($doc)
         $styleSheet = $this->styleSheetToDomDocument();
 
         $transpiler = $this->createTranspiler($styleSheet);
-        \libxml_use_internal_errors();
-        parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
-
-        return $transpiler->transform(function () use ($doc) {
-            return parent::transformToXml($doc);
-        });
+        $useInternalErrors = \libxml_use_internal_errors(true);
+
+        try {
+            parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
+            $this->throwOnLibxmlError();
+
+            return $transpiler->transform(function () use ($doc) {
+                return parent::transformToXml($doc);
+            });
+        } finally {
+            \libxml_clear_errors();
+            \libxml_use_internal_errors($useInternalErrors);
+        }
     }
 
     /**
@@ -82,11 +90,19 @@ public function transformToDoc($doc)
         $styleSheet = $this->styleSheetToDomDocument();
 
         $transpiler = $this->createTranspiler($styleSheet);
-        parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
-
-        return $transpiler->transform(function () use ($doc) {
-            return parent::transformToDoc($doc);
-        });
+        $useInternalErrors = \libxml_use_internal_errors(true);
+
+        try {
+            parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
+            $this->throwOnLibxmlError();
+
+            return $transpiler->transform(function () use ($doc) {
+                return parent::transformToDoc($doc);
+            });
+        } finally {
+            \libxml_clear_errors();
+            \libxml_use_internal_errors($useInternalErrors);
+        }
     }
 
     /**
@@ -97,13 +113,20 @@ public function transformToDoc($doc)
     public function transformToUri($doc, $uri)
     {
         $styleSheet = $this->styleSheetToDomDocument();
-
         $transpiler = $this->createTranspiler($styleSheet);
-        parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
-
-        return $transpiler->transform(function () use ($doc, $uri) {
-            return parent::transformToUri($doc, $uri);
-        });
+        $useInternalErrors = \libxml_use_internal_errors(true);
+
+        try {
+            parent::importStylesheet($this->getTranspiledStyleSheet($transpiler, $styleSheet));
+            $this->throwOnLibxmlError();
+
+            return $transpiler->transform(function () use ($doc, $uri) {
+                return parent::transformToUri($doc, $uri);
+            });
+        } finally {
+            \libxml_clear_errors();
+            \libxml_use_internal_errors($useInternalErrors);
+        }
     }
 
     /**
@@ -241,4 +264,14 @@ private function createStreamOptions(Transpiler $transpiler)
 
         return $contextOptions;
     }
+
+    private function throwOnLibxmlError()
+    {
+        $errors = \libxml_get_errors();
+        if ($errors === []) {
+            return;
+        }
+
+        throw TransformationException::fromLibxmlErrorList($errors);
+    }
 }
diff --git a/test/Integration/ExceptionTest.php b/test/Integration/ExceptionTest.php
@@ -0,0 +1,28 @@
+<?php
+declare(strict_types=1);
+
+namespace Genkgo\Xsl\Integration;
+
+use DOMDocument;
+use Genkgo\Xsl\AbstractTestCase;
+use Genkgo\Xsl\Cache\NullCache;
+use Genkgo\Xsl\Exception\TransformationException;
+use Genkgo\Xsl\XsltProcessor;
+
+final class ExceptionTest extends AbstractTestCase
+{
+    public function testException()
+    {
+        $this->expectException(TransformationException::class);
+
+        $xslDoc = new DOMDocument();
+        $xslDoc->loadXML((string)\file_get_contents('Stubs/invalid-stylesheet.xsl'));
+
+        $xmlDoc = new DOMDocument();
+        $xmlDoc->load('Stubs/collection.xml');
+
+        $transpiler = new XsltProcessor(new NullCache());
+        $transpiler->importStylesheet($xslDoc);
+        $transpiler->transformToXML($xmlDoc);
+    }
+}
diff --git a/test/Stubs/invalid-stylesheet.xsl b/test/Stubs/invalid-stylesheet.xsl
@@ -0,0 +1,3 @@
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1">
+    <xsl:variable match="/">test</xsl:variable>
+</xsl:stylesheet>