Add initialization from SimpleXMLElement object

Author: danmichaelo

README.md

@@ -29,9 +29,9 @@ composer require scriptotek/marc
 
 ## Reading records
 
-Use `Collection::fromFile` or `Collection::fromString` to read one or more
-MARC records from a file or string. The methods autodetect the data format
-(Binary XML or MARCXML) and whether the XML is namespaced or not.
+Use `Collection::fromFile`, `Collection::fromString` or `Collection::fromSimpleXMLElement`
+to read one or more MARC records from a file or string. The methods autodetect the data
+format (Binary XML or MARCXML) and whether the XML is namespaced or not.
 
 ```php
 use Scriptotek\Marc\Collection;
@@ -64,9 +64,9 @@ foreach ($records as $record) {
 }
 ```
 
-If you only have a single record, you can also use `Record::fromFile` or
-`Record::fromString`. These use the `Collection` methods under the hood,
-but returns a single `Record` object.
+If you only have a single record, you can also use `Record::fromFile`,
+`Record::fromString` or `Record::fromSimpleXMLElement`. These use the
+`Collection` methods under the hood, but returns a single `Record` object.
 
 ```php
 use Scriptotek\Marc\Record;

composer.json

@@ -15,7 +15,7 @@
         "ext-xml": "*",
         "ext-json": "*",
         "ck/file_marc_reference": "^1.2",
-        "pear/file_marc": "^1.1"
+        "pear/file_marc": "^1.4.1"
     },
     "require-dev": {
         "phpunit/phpunit": "^5.7 | ^6.0 | ^7.0",

src/Collection.php

@@ -6,6 +6,8 @@
 use Scriptotek\Marc\Exceptions\RecordNotFound;
 use Scriptotek\Marc\Exceptions\UnknownRecordType;
 use Scriptotek\Marc\Importers\Importer;
+use Scriptotek\Marc\Importers\XmlImporter;
+use SimpleXMLElement;
 
 class Collection implements \Iterator
 {
@@ -51,6 +53,19 @@ public static function fromString($data)
         return $importer->fromString($data);
     }
 
+    /**
+     * Load records from a SimpleXMLElement object.
+     *
+     * @param SimpleXMLElement $element
+     * @return Collection
+     */
+    public static function fromSimpleXMLElement(SimpleXMLElement $element)
+    {
+        $importer = new XmlImporter($element);
+
+        return $importer->getCollection();
+    }
+
     /**
      * Determines if a record is a bibliographic, holdings or authority record.
      *

src/Importers/Importer.php

@@ -5,6 +5,7 @@
 use File_MARC;
 use Scriptotek\Marc\Collection;
 use Scriptotek\Marc\Factory;
+use SimpleXMLElement;
 
 class Importer
 {

src/Importers/XmlImporter.php

@@ -4,6 +4,7 @@
 
 use File_MARCXML;
 use Scriptotek\Marc\Collection;
+use Scriptotek\Marc\Exceptions\RecordNotFound;
 use Scriptotek\Marc\Exceptions\XmlException;
 use Scriptotek\Marc\Factory;
 use SimpleXMLElement;
@@ -15,15 +16,30 @@ class XmlImporter
     /* var SimpleXMLElement */
     protected $source;
 
+    /**
+     * XmlImporter constructor.
+     *
+     * @param string|SimpleXMLElement $data  Filename, XML string or SimpleXMLElement object
+     * @param string $ns  URI or prefix of the namespace
+     * @param bool $isPrefix TRUE if $ns is a prefix, FALSE if it's a URI; defaults to FALSE
+     * @param string $factory  (optional) Object factory, probably no need to set this outside testing.
+     */
     public function __construct($data, $ns = '', $isPrefix = false, $factory = null)
     {
         $this->factory = isset($factory) ? $factory : new Factory();
 
+        if (is_a($data, SimpleXMLElement::class)) {
+            $this->source = $data;
+            return;
+        }
+
         if (strlen($data) < 256 && file_exists($data)) {
             $data = file_get_contents($data);
         }
 
+        // Store errors internally so that we can fetch them with libxml_get_errors() later
         libxml_use_internal_errors(true);
+
         $this->source = simplexml_load_string($data, 'SimpleXMLElement', 0, $ns, $isPrefix);
         if (false === $this->source) {
             throw new XmlException(libxml_get_errors());
@@ -69,6 +85,22 @@ public function getRecords()
         return [];
     }
 
+    public function getFirstRecord()
+    {
+        $records = $this->getRecords();
+        if (!count($records)) {
+            throw new RecordNotFound();
+        }
+
+        $record = $records[0];
+
+        list($prefix, $ns) = $this->getMarcNamespace($record->getNamespaces(true));
+
+        $parser = $this->factory->make('File_MARCXML', $record, File_MARCXML::SOURCE_SIMPLEXMLELEMENT, $ns);
+
+        return (new Collection($parser))->$this->getFirstRecord();
+    }
+
     public function getCollection()
     {
         $records = $this->getRecords();
@@ -77,6 +109,7 @@ public function getCollection()
         }
 
         list($prefix, $ns) = $this->getMarcNamespace($records[0]->getNamespaces(true));
+
         $pprefix = empty($prefix) ? '' : "$prefix:";
 
         $records = array_map(function (SimpleXMLElement $record) {

src/Record.php

@@ -10,6 +10,7 @@
 use Scriptotek\Marc\Exceptions\UnknownRecordType;
 use Scriptotek\Marc\Fields\ControlField;
 use Scriptotek\Marc\Fields\Field;
+use SimpleXMLElement;
 
 /**
  * The MARC record wrapper.
@@ -148,6 +149,21 @@ public static function fromString($data)
         return Collection::fromString($data)->first();
     }
 
+    /**
+     * Returns the first record found in the SimpleXMLElement object
+     *
+     * @param SimpleXMLElement $element
+     *   The SimpleXMLElement object in which to look for MARC records.
+     * @return BibliographicRecord|HoldingsRecord|AuthorityRecord
+     *   A wrapped MARC record.
+     * @throws RecordNotFound
+     *   When the object does not contain a MARC record.
+     */
+    public static function fromSimpleXMLElement(SimpleXMLElement $element)
+    {
+        return Collection::fromSimpleXMLElement($element)->first();
+    }
+
     /*************************************************************************
      * Query
      *************************************************************************/

tests/CollectionTest.php

@@ -75,4 +75,21 @@ public function testCollectionFromFile($filename, $expected)
         $this->assertCount($expected, $records);
         $this->assertInstanceOf(BibliographicRecord::class, $records[0]);
     }
+
+
+    /**
+     * Test that the sample files can be loaded using Collection::fromSimpleXMLElement.
+     *
+     * @dataProvider xmlFiles
+     * @param string $filename
+     * @param int $expected
+     */
+    public function testInitializeFromSimpleXmlElement($filename, $expected)
+    {
+        $el = simplexml_load_file($this->pathTo($filename));
+
+        $collection = Collection::fromSimpleXMLElement($el);
+
+        $this->assertCount($expected, $collection->toArray());
+    }
 }

tests/RecordTest.php

@@ -6,6 +6,7 @@
 use File_MARC_Record;
 use Scriptotek\Marc\AuthorityRecord;
 use Scriptotek\Marc\BibliographicRecord;
+use Scriptotek\Marc\Exceptions\RecordNotFound;
 use Scriptotek\Marc\Fields\Field;
 use Scriptotek\Marc\Fields\Subject;
 use Scriptotek\Marc\HoldingsRecord;
@@ -122,4 +123,40 @@ public function testGetRecord()
         // by the getter.
         $this->assertSame($wrapped_record, $wrapper->getRecord());
     }
+
+    /**
+     * Test that a Record wrapper object will not be initialized from
+     * an SimpleXMLElement object that doesn't contain a MARC record.
+     */
+    public function testInitializeFromInvalidSimpleXMLElement()
+    {
+        $source = simplexml_load_string(
+            '<?xml version="1.0" encoding="UTF-8" ?><book></book>'
+        );
+
+        $this->expectException(RecordNotFound::class);
+        $record = Record::fromSimpleXMLElement($source);
+    }
+
+    /**
+     * Test that a Record wrapper object can be initialized from
+     * a SimpleXMLElement object.
+     */
+    public function testInitializeFromSimpleXmlElement()
+    {
+        $source = simplexml_load_string('<?xml version="1.0" encoding="UTF-8" ?>
+          <record xmlns="http://www.loc.gov/MARC21/slim">
+            <leader>99999cam a2299999 u 4500</leader>
+            <controlfield tag="001">98218834x</controlfield>
+            <datafield tag="020" ind1=" " ind2=" ">
+              <subfield code="a">8200424421</subfield>
+              <subfield code="q">h.</subfield>
+              <subfield code="c">Nkr 98.00</subfield>
+            </datafield>
+          </record>');
+
+        $record = Record::fromSimpleXMLElement($source);
+        $this->assertInstanceOf(Record::class, $record);
+        $this->assertInstanceOf(BibliographicRecord::class, $record);
+    }
 }