1<?php
2
3namespace MongoDB\Operation;
4
5use MongoDB\Driver\Server;
6use MongoDB\Exception\InvalidArgumentException;
7
8/**
9 * Operation for finding a single document with the find command.
10 *
11 * @api
12 * @see MongoDB\Collection::findOne()
13 * @see http://docs.mongodb.org/manual/tutorial/query-documents/
14 * @see http://docs.mongodb.org/manual/reference/operator/query-modifier/
15 */
16class FindOne implements Executable
17{
18    private $find;
19    private $options;
20
21    /**
22     * Constructs a find command for finding a single document.
23     *
24     * Supported options:
25     *
26     *  * comment (string): Attaches a comment to the query. If "$comment" also
27     *    exists in the modifiers document, this option will take precedence.
28     *
29     *  * maxTimeMS (integer): The maximum amount of time to allow the query to
30     *    run. If "$maxTimeMS" also exists in the modifiers document, this
31     *    option will take precedence.
32     *
33     *  * modifiers (document): Meta-operators modifying the output or behavior
34     *    of a query.
35     *
36     *  * projection (document): Limits the fields to return for the matching
37     *    document.
38     *
39     *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
40     *
41     *    For servers < 3.2, this option is ignored as read concern is not
42     *    available.
43     *
44     *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
45     *
46     *  * skip (integer): The number of documents to skip before returning.
47     *
48     *  * sort (document): The order in which to return matching documents. If
49     *    "$orderby" also exists in the modifiers document, this option will
50     *    take precedence.
51     *
52     *  * typeMap (array): Type map for BSON deserialization.
53     *
54     * @param string       $databaseName   Database name
55     * @param string       $collectionName Collection name
56     * @param array|object $filter         Query by which to filter documents
57     * @param array        $options        Command options
58     * @throws InvalidArgumentException
59     */
60    public function __construct($databaseName, $collectionName, $filter, array $options = [])
61    {
62        $this->find = new Find(
63            $databaseName,
64            $collectionName,
65            $filter,
66            ['limit' => 1] + $options
67        );
68
69        $this->options = $options;
70    }
71
72    /**
73     * Execute the operation.
74     *
75     * @see Executable::execute()
76     * @param Server $server
77     * @return array|object|null
78     */
79    public function execute(Server $server)
80    {
81        $cursor = $this->find->execute($server);
82        $document = current($cursor->toArray());
83
84        return ($document === false) ? null : $document;
85    }
86}
87