refactor: Merge Collection and Records [BC]

- `Collection::fromOaiPmhResponse()` has been removed. Use `Collection::fromString()` instead.

- `Collection::records` has been removed. Records are now available directly on the `Collection` class.

- `Record::fromString` now throws a `RecordNotFound` exception rather than an `ErrorException` exception if no record was found.

Author: danmichaelo

README.md

@@ -30,7 +30,7 @@ Binary MARC or XML (namespaced or not).
 use Scriptotek\Marc\Collection;
 
 $collection = Collection::fromFile($someFileName);
-foreach ($collection->records as $record) {
+foreach ($collection as $record) {
     echo $record->getField('250')->getSubfield('a')->getData() . "\n";
 }
 ```
@@ -47,8 +47,8 @@ $response = file_get_contents('http://lx2.loc.gov:210/lcdb?' . http_build_query(
     'query'          => 'bath.isbn=0761532692',
 ]));
 
-$collection = Collection::fromString($response);
-foreach ($collection->records as $record) {
+$records = Collection::fromString($response);
+foreach ($records as $record) {
     ...
 }
 

src/Collection.php

@@ -3,70 +3,114 @@
 namespace Scriptotek\Marc;
 
 use Scriptotek\Marc\Importers\Importer;
-use Scriptotek\Marc\Importers\XmlImporter;
-use Scriptotek\Marc\Importers\SruResponse;
 
-class Collection
+class Collection implements \Iterator
 {
     protected $parser;
     protected $_records;
+    protected $useCache = false;
+    protected $position = 0;
+    protected $_current;
+
+    /**
+     * Collection constructor.
+     *
+     * @param \File_MARC|\File_MARCXML $parser
+     */
+    public function __construct($parser = null)
+    {
+        $this->parser = $parser;
+    }
 
+    /**
+     * Load records from a file (Binary MARC or XML).
+     *
+     * @param string $filename
+     * @return Collection
+     */
     public static function fromFile($filename)
     {
-        $importer = new Importer($filename, true);
+        $importer = new Importer();
 
-        return $importer->getCollection();
+        return $importer->fromFile($filename);
     }
 
+    /**
+     * Load records from a string (Binary MARC or XML).
+     *
+     * @param string $data
+     * @return Collection
+     */
     public static function fromString($data)
     {
-        $importer = new Importer($data, false);
+        $importer = new Importer();
 
-        return $importer->getCollection();
+        return $importer->fromString($data);
     }
 
-    public static function fromOaiPmhResponse($data)
+    /**
+     * Returns an array representation of the collection.
+     *
+     * @return Collection[]
+     */
+    public function toArray()
     {
-        $importer = new XmlImporter($data);
-
-        return $importer->getCollection();
+        return iterator_to_array($this);
     }
 
-    public static function fromSruResponse($data)
+    /*********************************************************
+     * Iterator
+     *********************************************************/
+
+    public function valid()
     {
-        $importer = new SruResponse($data);
+        return !is_null($this->_current);
+    }
 
-        return $importer->getCollection();
+    public function current()
+    {
+        return $this->_current;
     }
 
-    public function __construct(\Factory $factory = null)
+    public function key()
     {
-        $this->factory = $factory ?: new Factory();
+        return $this->position;
     }
 
-    public function parse($source, $isXml, $ns = '', $isPrefix = true)
+    public function next()
     {
-        if ($isXml) {
-            $this->parser = $this->factory->make('File_MARCXML', $source, \File_MARCXML::SOURCE_STRING, $ns, $isPrefix);
+        ++$this->position;
+        if ($this->useCache) {
+            $rec = isset($this->_records[$this->position]) ? $this->_records[$this->position] : false;
         } else {
-            $this->parser = $this->factory->make('File_MARC', $source, \File_MARC::SOURCE_STRING);
+            $rec = isset($this->parser) ? $this->parser->next() : null;
+            if ($rec) {
+                $rec = new Record($rec);
+                $this->_records[] = $rec;
+            }
         }
+        $this->_current = $rec ?: null;
     }
 
-    public function __get($key = '')
+    public function rewind()
     {
-        if ($key == 'records') {
-            if (is_null($this->parser)) {
-                $this->_records = new Records();
-            }
-            if (is_null($this->_records)) {
-                $this->_records = new Records($this->parser);
-            }
-
-            return $this->_records;
+        $this->position = -1;
+        if (is_null($this->_records)) {
+            $this->_records = [];
+        } else {
+            $this->useCache = true;
         }
+        $this->next();
     }
 
+    // public function count()
+    // {
+    // }
+
+    /*********************************************************
+     * Magic
+     *********************************************************/
+
     public function __call($name, $arguments)
     {
         return call_user_func_array(array($this->parser, $name), $arguments);

src/Exceptions/RecordNotFound.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Scriptotek\Marc\Exceptions;
+
+class RecordNotFound extends \RuntimeException
+{
+}

src/Importers/Importer.php

@@ -2,32 +2,34 @@
 
 namespace Scriptotek\Marc\Importers;
 
+use File_MARC;
 use Scriptotek\Marc\Collection;
+use Scriptotek\Marc\Factory;
 
 class Importer
 {
-    protected $data;
+    public function __construct(Factory $factory = null)
+    {
+        $this->factory = isset($factory) ? $factory : new Factory();
+    }
 
-    public function __construct($data, $isFile)
+    public function fromFile($filename)
     {
-        if ($isFile) {
-            $data = file_get_contents($data);
-        }
-        $this->data = trim($data);
+        $data = file_get_contents($filename);
+
+        return $this->fromString($data);
     }
 
-    public function getCollection()
+    public function fromString($data)
     {
-        $isXml = (substr($this->data, 0, 1) == '<');
+        $isXml = (substr($data, 0, 1) == '<');
         if ($isXml) {
-            $importer = new XmlImporter($this->data);
+            $importer = new XmlImporter($data);
 
             return $importer->getCollection();
         } else {
-            $c = new Collection();
-            $c->parse($this->data, false);
-
-            return $c;
+            $parser = $this->factory->make('File_MARC', $data, File_MARC::SOURCE_STRING);
+            return new Collection($parser);
         }
     }
 }

src/Importers/XmlImporter.php

@@ -2,17 +2,19 @@
 
 namespace Scriptotek\Marc\Importers;
 
+use File_MARCXML;
 use Scriptotek\Marc\Collection;
 use Scriptotek\Marc\Exceptions\XmlException;
+use Scriptotek\Marc\Factory;
 
 class XmlImporter
 {
+    protected $factory;
     protected $source;
-    protected $collection;
 
-    public function __construct($data, $ns = '', $isPrefix = false, Collection $collection = null)
+    public function __construct($data, $ns = '', $isPrefix = false, $factory = null)
     {
-        $this->collection = $collection ?: new Collection();
+        $this->factory = isset($factory) ? $factory : new Factory();
 
         if (strlen($data) < 256 && file_exists($data)) {
             $data = file_get_contents($data);
@@ -68,7 +70,7 @@ public function getCollection()
     {
         $records = $this->getRecords();
         if (!count($records)) {
-            return $this->collection;
+            return new Collection();
         }
 
         list($prefix, $ns) = $this->getMarcNamespace($records[0]->getNamespaces(true));
@@ -98,8 +100,8 @@ public function getCollection()
             implode('', $records) .
             '</' . $pprefix . 'collection>';
 
-        $this->collection->parse($marcCollection, true, $prefix);
+        $parser = $this->factory->make('File_MARCXML', $marcCollection, File_MARCXML::SOURCE_STRING, $prefix, true);
 
-        return $this->collection;
+        return new Collection($parser);
     }
 }

src/Record.php

@@ -2,36 +2,58 @@
 
 namespace Scriptotek\Marc;
 
+use File_MARC_Record;
 use File_MARC_Reference;
+use Scriptotek\Marc\Exceptions\RecordNotFound;
 
 class Record
 {
     protected $record;
     protected $factory;
 
-    public function __construct(\File_MARC_Record $record, Factory $factory = null)
+    /**
+     * Record constructor.
+     * @param File_MARC_Record $record
+     * @param Factory|null $factory
+     */
+    public function __construct(File_MARC_Record $record, Factory $factory = null)
     {
         $this->record = $record;
         $this->factory = $factory ?: new Factory();
     }
 
+    /**
+     * Returns the first record found in the file $filename, or null if no records found.
+     *
+     * @param $filename
+     * @return null|Collection
+     */
     public static function fromFile($filename)
     {
-        $collection = Collection::fromFile($filename);
+        $records = Collection::fromFile($filename)->toArray();
 
-        return $collection->records->toArray()[0];
+        if (!count($records)) {
+            throw new RecordNotFound();
+        }
+
+        return $records[0];
     }
 
+    /**
+     * Returns the first record found in the string $data, or null if no records found.
+     *
+     * @param $data
+     * @return null|Collection
+     */
     public static function fromString($data)
     {
-        $collection = Collection::fromString($data);
+        $records = Collection::fromString($data)->toArray();
 
-        $recs = $collection->records->toArray();
-        if (!count($recs)) {
-            throw new \ErrorException('Record not found');
+        if (!count($records)) {
+            throw new RecordNotFound();
         }
 
-        return $recs[0];
+        return $records[0];
     }
 
     /*************************************************************************