PHPLIB-72: Use model class when listing databases

Author: jmikola

src/Client.php

@@ -7,7 +7,8 @@
 use MongoDB\Driver\Manager;
 use MongoDB\Driver\ReadPreference;
 use MongoDB\Driver\WriteConcern;
-use ArrayIterator;
+use MongoDB\Model\DatabaseInfoIterator;
+use MongoDB\Model\DatabaseInfoLegacyIterator;
 use stdClass;
 use UnexpectedValueException;
 
@@ -54,7 +55,7 @@ public function dropDatabase($databaseName)
      * List databases.
      *
      * @see http://docs.mongodb.org/manual/reference/command/listDatabases/
-     * @return Traversable
+     * @return DatabaseInfoIterator
      * @throws UnexpectedValueException if the command result is malformed
      */
     public function listDatabases()
@@ -73,13 +74,13 @@ function(stdClass $database) { return (array) $database; },
             $result['databases']
         );
 
-        /* Return a Traversable instead of an array in case listDatabases is
+        /* Return an Iterator instead of an array in case listDatabases is
          * eventually changed to return a command cursor, like the collection
          * and index enumeration commands. This makes the "totalSize" command
          * field inaccessible, but users can manually invoke the command if they
          * need that value.
          */
-        return new ArrayIterator($databases);
+        return new DatabaseInfoLegacyIterator($databases);
     }
 
     /**

src/Model/DatabaseInfo.php

@@ -0,0 +1,52 @@
+<?php
+
+namespace MongoDB\Model;
+
+class DatabaseInfo
+{
+    private $empty;
+    private $name;
+    private $sizeOnDisk;
+
+    /**
+    * Constructor.
+    *
+    * @param array $info Database info
+    */
+    public function __construct(array $info)
+    {
+        $this->name = (string) $info['name'];
+        $this->empty = (boolean) $info['empty'];
+        $this->sizeOnDisk = (integer) $info['sizeOnDisk'];
+    }
+
+    /**
+     * Return the database name.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * Return the databases size on disk (in bytes).
+     *
+     * @return integer
+     */
+    public function getSizeOnDisk()
+    {
+        return $this->sizeOnDisk;
+    }
+
+    /**
+     * Return whether the database is empty.
+     *
+     * @return boolean
+     */
+    public function isEmpty()
+    {
+        return $this->empty;
+    }
+}

src/Model/DatabaseInfoIterator.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace MongoDB\Model;
+
+use Iterator;
+
+interface DatabaseInfoIterator extends Iterator
+{
+    /**
+     * Return the current element as a DatabaseInfo instance.
+     *
+     * @return DatabaseInfo
+     */
+    public function current();
+}

src/Model/DatabaseInfoLegacyIterator.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace MongoDB\Model;
+
+class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
+{
+    private $databases;
+    private $index = 0;
+
+    /**
+     * Constructor.
+     *
+     * @param array $databases
+     */
+    public function __construct(array $databases)
+    {
+        $this->databases = $databases;
+    }
+
+    /**
+     * Return the current element as a DatabaseInfo instance.
+     *
+     * @see DatabaseInfoIterator::current()
+     * @see http://php.net/iterator.current
+     * @return DatabaseInfo
+     */
+    public function current()
+    {
+        return new DatabaseInfo(current($this->databases));
+    }
+
+    /**
+     * Return the key of the current element.
+     *
+     * @see http://php.net/iterator.key
+     * @return integer
+     */
+    public function key()
+    {
+        return key($this->databases);
+    }
+
+    /**
+     * Move forward to next element.
+     *
+     * @see http://php.net/iterator.next
+     */
+    public function next()
+    {
+        next($this->databases);
+    }
+
+    /**
+     * Rewind the Iterator to the first element.
+     *
+     * @see http://php.net/iterator.rewind
+     */
+    public function rewind()
+    {
+        reset($this->databases);
+    }
+
+    /**
+     * Checks if current position is valid.
+     *
+     * @see http://php.net/iterator.valid
+     * @return boolean
+     */
+    public function valid()
+    {
+        return key($this->databases) !== null;
+    }
+}

tests/ClientFunctionalTest.php

@@ -3,19 +3,30 @@
 namespace MongoDB\Tests;
 
 use MongoDB\Client;
+use MongoDB\Driver\Command;
+use MongoDB\Model\DatabaseInfo;
 
 /**
  * Functional tests for the Client class.
  */
 class ClientFunctionalTest extends FunctionalTestCase
 {
+    private $client;
+
+    public function setUp()
+    {
+        parent::setUp();
+
+        $this->client = new Client($this->getUri());
+        $this->client->dropDatabase($this->getDatabaseName());
+    }
+
     public function testDropDatabase()
     {
         $writeResult = $this->manager->executeInsert($this->getNamespace(), array('x' => 1));
         $this->assertEquals(1, $writeResult->getInsertedCount());
 
-        $client = new Client($this->getUri());
-        $commandResult = $client->dropDatabase($this->getDatabaseName());
+        $commandResult = $this->client->dropDatabase($this->getDatabaseName());
         $this->assertCommandSucceeded($commandResult);
         $this->assertCollectionCount($this->getNamespace(), 0);
     }
@@ -25,22 +36,52 @@ public function testListDatabases()
         $writeResult = $this->manager->executeInsert($this->getNamespace(), array('x' => 1));
         $this->assertEquals(1, $writeResult->getInsertedCount());
 
-        $client = new Client($this->getUri());
-        $databases = $client->listDatabases();
+        $databases = $this->client->listDatabases();
+
+        $this->assertInstanceOf('MongoDB\Model\DatabaseInfoIterator', $databases);
+
+        foreach ($databases as $database) {
+            $this->assertInstanceOf('MongoDB\Model\DatabaseInfo', $database);
+        }
+
+        $that = $this;
+        $this->assertDatabaseExists($this->getDatabaseName(), function(DatabaseInfo $info) use ($that) {
+            $that->assertFalse($info->isEmpty());
+            $that->assertGreaterThan(0, $info->getSizeOnDisk());
+        });
+    }
+
+    /**
+     * Asserts that a database with the given name exists on the server.
+     *
+     * An optional $callback may be provided, which should take a DatabaseInfo
+     * argument as its first and only parameter. If a DatabaseInfo matching
+     * the given name is found, it will be passed to the callback, which may
+     * perform additional assertions.
+     *
+     * @param callable $callback
+     */
+    private function assertDatabaseExists($databaseName, $callback = null)
+    {
+        if ($callback !== null && ! is_callable($callback)) {
+            throw new InvalidArgumentException('$callback is not a callable');
+        }
 
-        $this->assertInstanceOf('Traversable', $databases);
+        $databases = $this->client->listDatabases();
 
         $foundDatabase = null;
 
         foreach ($databases as $database) {
-            if ($database['name'] === $this->getDatabaseName()) {
+            if ($database->getName() === $databaseName) {
                 $foundDatabase = $database;
                 break;
             }
         }
 
-        $this->assertNotNull($foundDatabase, 'Found test database in list of databases');
-        $this->assertFalse($foundDatabase['empty'], 'Test database is not empty');
-        $this->assertGreaterThan(0, $foundDatabase['sizeOnDisk'], 'Test database takes up disk space');
+        $this->assertNotNull($foundDatabase, sprintf('Found %s database on the server', $databaseName));
+
+        if ($callback !== null) {
+            call_user_func($callback, $foundDatabase);
+        }
     }
 }