PHPLIB-46: Index info and corresponding iterator class

src/Model/IndexInfo.php

+<?php
+
+namespace MongoDB\Model;
+
+use ArrayAccess;
+use BadMethodCallException;
+
+/**
+ * Index information model class.
+ *
+ * This class models the index information returned by the listIndexes command
+ * or, for legacy servers, queries on the "system.indexes" collection. It
+ * provides methods to access common index options, and allows access to other
+ * options through the ArrayAccess interface (write methods are not supported).
+ * For information on keys and index options, see the referenced
+ * db.collection.createIndex() documentation.
+ *
+ * @api
+ * @see MongoDB\Collection::listIndexes()
+ * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst
+ * @see http://docs.mongodb.org/manual/reference/method/db.collection.createIndex/
+ */
+class IndexInfo implements ArrayAccess
+{
+    private $info;
+
+    /**
+    * Constructor.
+    *
+    * @param array $info Index info
+    */
+    public function __construct(array $info)
+    {
+        $this->info = $info;
+    }
+
+    /**
+     * Return the index key(s).
+     *
+     * @return array
+     */
+    public function getKeys()
+    {
+        return (array) $this->info['key'];
+    }
+
+    /**
+     * Return the index name.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return (string) $this->info['name'];
+    }
+
+    /**
+     * Return the index namespace (e.g. "db.collection").
+     *
+     * @return string
+     */
+    public function getNamespace()
+    {
+        return (string) $this->info['ns'];
+    }
+
+    /**
+     * Return the index version.
+     *
+     * @return integer
+     */
+    public function getVersion()
+    {
+        return (integer) $this->info['v'];
+    }
+
+    /**
+     * Return whether this is a sparse index.
+     *
+     * @see http://docs.mongodb.org/manual/core/index-sparse/
+     * @return boolean
+     */
+    public function isSparse()
+    {
+        return ! empty($this->info['sparse']);
+    }
+
+    /**
+     * Return whether this is a TTL index.
+     *
+     * @see http://docs.mongodb.org/manual/core/index-ttl/
+     * @return boolean
+     */
+    public function isTtl()
+    {
+        return array_key_exists('expireAfterSeconds', $this->info);
+    }
+
+    /**
+     * Return whether this is a unique index.
+     *
+     * @see http://docs.mongodb.org/manual/core/index-unique/
+     * @return boolean
+     */
+    public function isUnique()
+    {
+        return ! empty($this->info['unique']);
+    }
+
+    /**
+     * Check whether a field exists in the index information.
+     *
+     * @see http://php.net/arrayaccess.offsetexists
+     * @param mixed $key
+     * @return boolean
+     */
+    public function offsetExists($key)
+    {
+        return array_key_exists($key, $this->info);
+    }
+
+    /**
+     * Return the field's value from the index information.
+     *
+     * This method satisfies the Enumerating Indexes specification's requirement
+     * that index fields be made accessible under their original names. It may
+     * also be used to access fields that do not have a helper method.
+     *
+     * @see http://php.net/arrayaccess.offsetget
+     * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst#getting-full-index-information
+     * @param mixed $key
+     * @return mixed
+     */
+    public function offsetGet($key)
+    {
+        return $this->data[$key];
+    }
+
+    /**
+     * Not supported.
+     *
+     * @see http://php.net/arrayaccess.offsetset
+     * @throws BadMethodCallException IndexInfo is read-only
+     */
+    public function offsetSet($key, $value)
+    {
+        throw new BadMethodCallException('IndexInfo is read-only');
+    }
+
+    /**
+     * Not supported.
+     *
+     * @see http://php.net/arrayaccess.offsetunset
+     * @throws BadMethodCallException IndexInfo is read-only
+     */
+    public function offsetUnset($key)
+    {
+        throw new BadMethodCallException('IndexInfo is read-only');
+    }
+}

src/Model/IndexInfoIterator.php

+<?php
+
+namespace MongoDB\Model;
+
+use Iterator;
+
+/**
+ * IndexInfoIterator interface.
+ *
+ * This iterator is used for enumerating indexes in a collection.
+ *
+ * @api
+ * @see MongoDB\Collection::listIndexes()
+ */
+interface IndexInfoIterator extends Iterator
+{
+    /**
+     * Return the current element as a IndexInfo instance.
+     *
+     * @return IndexInfo
+     */
+    public function current();
+}

src/Model/IndexInfoIteratorIterator.php

+<?php
+
+namespace MongoDB\Model;
+
+use IteratorIterator;
+
+/**
+ * IndexInfoIterator for both listIndexes command and legacy query results.
+ *
+ * This common iterator may be used to wrap a Cursor returned by both the
+ * listIndexes command and, for legacy servers, queries on the "system.indexes"
+ * collection.
+ *
+ * @internal
+ * @see MongoDB\Collection::listIndexes()
+ * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst
+ * @see http://docs.mongodb.org/manual/reference/command/listIndexes/
+ * @see http://docs.mongodb.org/manual/reference/system-collections/
+ */
+class IndexInfoIteratorIterator extends IteratorIterator implements IndexInfoIterator
+{
+    /**
+     * Return the current element as an IndexInfo instance.
+     *
+     * @see IndexInfoIterator::current()
+     * @see http://php.net/iterator.current
+     * @return IndexInfo
+     */
+    public function current()
+    {
+        return new IndexInfo(parent::current());
+    }
+}