repo_mongoPhp7/lib/Mongo/MongoCursor.php

<?php
/*
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

use Alcaeus\MongoDbAdapter\TypeConverter;
use MongoDB\Collection;
use MongoDB\Driver\Cursor;
use MongoDB\Driver\ReadPreference;
use MongoDB\Operation\Find;

/**
 * Result object for database query.
 * @link http://www.php.net/manual/en/class.mongocursor.php
 */
class MongoCursor implements Iterator
{
    /**
     * @var bool
     */
    public static $slaveOkay = false;

    /**
     * @var int
     */
    static $timeout = 30000;

    /**
     * @var MongoClient
     */
    private $connection;

    /**
     * @var string
     */
    private $ns;

    /**
     * @var array
     */
    private $query;

    /**
     * @var
     */
    private $filter;

    /**
     * @var Collection
     */
    private $collection;

    /**
     * @var Cursor
     */
    private $cursor;

    /**
     * @var IteratorIterator
     */
    private $iterator;

    private $allowPartialResults;
    private $awaitData;
    private $batchSize;
    private $flags;
    private $hint;
    private $limit;
    private $maxTimeMS;
    private $noCursorTimeout;
    private $oplogReplay;
    private $options = [];
    private $projection;
    private $readPreference = [];
    private $skip;
    private $snapshot;
    private $sort;
    private $tailable;

    /**
     * Create a new cursor
     * @link http://www.php.net/manual/en/mongocursor.construct.php
     * @param MongoClient $connection Database connection.
     * @param string $ns Full name of database and collection.
     * @param array $query Database query.
     * @param array $fields Fields to return.
     * @return MongoCursor Returns the new cursor
     */
    public function __construct(MongoClient $connection, $ns, array $query = array(), array $fields = array())
    {
        $this->connection = $connection;
        $this->ns = $ns;
        $this->query = $query;
        $this->projection = $fields;

        $nsParts = explode('.', $ns);
        $db = array_shift($nsParts);

        $this->collection = $connection->selectCollection($db, implode('.', $nsParts))->getCollection();
    }

    /**
     * Adds a top-level key/value pair to a query
     * @link http://www.php.net/manual/en/mongocursor.addoption.php
     * @param string $key Fieldname to add.
     * @param mixed $value Value to add.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function addOption($key, $value)
    {
        $this->errorIfOpened();
        $this->options[$key] = $value;

        return $this;
    }

    /**
     * (PECL mongo &gt;= 1.2.11)<br/>
     * Sets whether this cursor will wait for a while for a tailable cursor to return more data
     * @param bool $wait [optional] <p>If the cursor should wait for more data to become available.</p>
     * @return MongoCursor Returns this cursor.
     */
    public function awaitData($wait = true)
    {
        $this->errorIfOpened();
        $this->awaitData = $wait;

        return $this;
    }

    /**
     * Limits the number of elements returned in one batch.
     *
     * @link http://docs.php.net/manual/en/mongocursor.batchsize.php
     * @param int $batchSize The number of results to return per batch
     * @return MongoCursor Returns this cursor.
     */
    public function batchSize($batchSize)
    {
        $this->errorIfOpened();
        $this->batchSize = $batchSize;

        return $this;
    }

    /**
     * Counts the number of results for this query
     * @link http://www.php.net/manual/en/mongocursor.count.php
     * @param bool $foundOnly Send cursor limit and skip information to the count function, if applicable.
     * @return int The number of documents returned by this cursor's query.
     */
    public function count($foundOnly = false)
    {
        if ($foundOnly && $this->cursor !== null) {
            return iterator_count($this->ensureIterator());
        }

        $optionNames = ['hint', 'limit', 'maxTimeMS', 'skip'];
        $options = $foundOnly ? $this->applyOptions($this->options, $optionNames) : $this->options;

        return $this->collection->count($this->query, $options);
    }

    /**
     * Returns the current element
     * @link http://www.php.net/manual/en/mongocursor.current.php
     * @return array
     */
    public function current()
    {
        $document = $this->ensureIterator()->current();
        if ($document !== null) {
            $document = TypeConverter::convertObjectToLegacyArray($document);
        }

        return $document;
    }

    /**
     * Checks if there are documents that have not been sent yet from the database for this cursor
     * @link http://www.php.net/manual/en/mongocursor.dead.php
     * @return boolean Returns if there are more results that have not been sent to the client, yet.
     */
    public function dead()
    {
        return $this->ensureCursor()->isDead();
    }

    /**
     * Execute the query
     * @link http://www.php.net/manual/en/mongocursor.doquery.php
     * @throws MongoConnectionException if it cannot reach the database.
     * @return void
     */
    protected function doQuery()
    {
        $options = $this->applyOptions($this->options);

        $this->cursor = $this->collection->find($this->query, $options);
    }

    /**
     * Return an explanation of the query, often useful for optimization and debugging
     * @link http://www.php.net/manual/en/mongocursor.explain.php
     * @return array Returns an explanation of the query.
     */
    public function explain()
    {
        $this->notImplemented();
    }

    /**
     * Sets the fields for a query
     * @link http://www.php.net/manual/en/mongocursor.fields.php
     * @param array $f Fields to return (or not return).
     * @throws MongoCursorException
     * @return MongoCursor
     */
    public function fields(array $f)
    {
        $this->errorIfOpened();
        $this->projection = $f;

        return $this;
    }

    /**
     * Return the next object to which this cursor points, and advance the cursor
     * @link http://www.php.net/manual/en/mongocursor.getnext.php
     * @throws MongoConnectionException
     * @throws MongoCursorTimeoutException
     * @return array Returns the next object
     */
    public function getNext()
    {
        $this->next();

        return $this->current();
    }

    /**
     * Get the read preference for this query
     * @link http://www.php.net/manual/en/mongocursor.getreadpreference.php
     * @return array
     */
    public function getReadPreference()
    {
        return $this->readPreference;
    }

    /**
     * Checks if there are any more elements in this cursor
     * @link http://www.php.net/manual/en/mongocursor.hasnext.php
     * @throws MongoConnectionException
     * @throws MongoCursorTimeoutException
     * @return bool Returns true if there is another element
     */
    public function hasNext()
    {
        $this->errorIfOpened();
        $this->notImplemented();
    }

    /**
     * Gives the database a hint about the query
     * @link http://www.php.net/manual/en/mongocursor.hint.php
     * @param array|string $keyPattern Indexes to use for the query.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function hint($keyPattern)
    {
        $this->errorIfOpened();
        $this->hint = $keyPattern;

        return $this;
    }

    /**
     * Sets whether this cursor will timeout
     * @link http://www.php.net/manual/en/mongocursor.immortal.php
     * @param bool $liveForever If the cursor should be immortal.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function immortal($liveForever = true)
    {
        $this->errorIfOpened();
        $this->noCursorTimeout = $liveForever;

        return $this;
    }

    /**
     * Gets the query, fields, limit, and skip for this cursor
     * @link http://www.php.net/manual/en/mongocursor.info.php
     * @return array The query, fields, limit, and skip for this cursor as an associative array.
     */
    public function info()
    {
        $info = [
            'ns' => $this->ns,
            'limit' => $this->limit,
            'batchSize' => $this->batchSize,
            'skip' => $this->skip,
            'flags' => $this->flags,
            'query' => $this->query,
            'fields' => $this->projection,
            'started_iterating' => $this->cursor !== null,
        ];

        if ($info['started_iterating']) {
            switch ($this->cursor->getServer()->getType()) {
                case \MongoDB\Driver\Server::TYPE_ARBITER:
                    $typeString = 'ARBITER';
                    break;
                case \MongoDB\Driver\Server::TYPE_MONGOS:
                    $typeString = 'MONGOS';
                    break;
                case \MongoDB\Driver\Server::TYPE_PRIMARY:
                    $typeString = 'PRIMARY';
                    break;
                case \MongoDB\Driver\Server::TYPE_SECONDARY:
                    $typeString = 'SECONDARY';
                    break;
                default:
                    $typeString = 'STANDALONE';
            }

            $info = array_merge($info, [
                'id' => (string) $this->cursor->getId(),
                'at' => null, // @todo Complete info for cursor that is iterating
                'numReturned' => null, // @todo Complete info for cursor that is iterating
                'server' => null, // @todo Complete info for cursor that is iterating
                'host' => $this->cursor->getServer()->getHost(),
                'port' => $this->cursor->getServer()->getPort(),
                'connection_type_desc' => $typeString,
            ]);
        }

        return $info;
    }

    /**
     * Returns the current result's _id
     * @link http://www.php.net/manual/en/mongocursor.key.php
     * @return string The current result's _id as a string.
     */
    public function key()
    {
        return $this->ensureIterator()->key();
    }

    /**
     * Limits the number of results returned
     * @link http://www.php.net/manual/en/mongocursor.limit.php
     * @param int $num The number of results to return.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function limit($num)
    {
        $this->errorIfOpened();
        $this->limit = $num;

        return $this;
    }

    /**
     * @param int $ms
     * @return $this
     * @throws MongoCursorException
     */
    public function maxTimeMS($ms)
    {
        $this->errorIfOpened();
        $this->maxTimeMS = $ms;

        return $this;
    }

    /**
     * Advances the cursor to the next result
     * @link http://www.php.net/manual/en/mongocursor.next.php
     * @throws MongoConnectionException
     * @throws MongoCursorTimeoutException
     * @return void
     */
    public function next()
    {
        $this->ensureIterator()->next();
    }

    /**
     * @link http://www.php.net/manual/en/mongocursor.partial.php
     * @param bool $okay [optional] <p>If receiving partial results is okay.</p>
     * @return MongoCursor Returns this cursor.
     */
    public function partial($okay = true)
    {
        $this->allowPartialResults = $okay;

        return $this;
    }

    /**
     * Clears the cursor
     * @link http://www.php.net/manual/en/mongocursor.reset.php
     * @return void
     */
    public function reset()
    {
        $this->cursor = null;
        $this->iterator = null;
    }

    /**
     * Returns the cursor to the beginning of the result set
     * @throws MongoConnectionException
     * @throws MongoCursorTimeoutException
     * @return void
     */
    public function rewind()
    {
        // Note: rewinding the cursor means recreating it internally
        $this->reset();
        $this->ensureIterator()->rewind();
    }

    /**
     * @link http://www.php.net/manual/en/mongocursor.setflag.php
     * @param int $flag
     * @param bool $set
     * @return MongoCursor
     */
    public function setFlag($flag, $set = true)
    {
        $this->notImplemented();
    }

    /**
     * @link http://www.php.net/manual/en/mongocursor.setreadpreference.php
     * @param string $readPreference
     * @param array $tags
     * @return MongoCursor Returns this cursor.
     */
    public function setReadPreference($readPreference, array $tags = [])
    {
        $availableReadPreferences = [
            MongoClient::RP_PRIMARY,
            MongoClient::RP_PRIMARY_PREFERRED,
            MongoClient::RP_SECONDARY,
            MongoClient::RP_SECONDARY_PREFERRED,
            MongoClient::RP_NEAREST
        ];
        if (! in_array($readPreference, $availableReadPreferences)) {
            trigger_error("The value '$readPreference' is not valid as read preference type", E_WARNING);
            return $this;
        }

        if ($readPreference == MongoClient::RP_PRIMARY && count($tags)) {
            trigger_error("You can't use read preference tags with a read preference of PRIMARY", E_WARNING);
            return $this;
        }

        $this->readPreference = [
            'type' => $readPreference,
            'tagsets' => $tags
        ];

        return $this;
    }

    /**
     * Skips a number of results
     * @link http://www.php.net/manual/en/mongocursor.skip.php
     * @param int $num The number of results to skip.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function skip($num)
    {
        $this->errorIfOpened();
        $this->skip = $num;

        return $this;
    }

    /**
     * Sets whether this query can be done on a slave
     * This method will override the static class variable slaveOkay.
     * @link http://www.php.net/manual/en/mongocursor.slaveOkay.php
     * @param boolean $okay If it is okay to query the slave.
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function slaveOkay($okay = true)
    {
        $this->errorIfOpened();
        static::$slaveOkay = $okay;
    }

    /**
     * Use snapshot mode for the query
     * @link http://www.php.net/manual/en/mongocursor.snapshot.php
     * @throws MongoCursorException
     * @return MongoCursor Returns this cursor
     */
    public function snapshot()
    {
        $this->errorIfOpened();
        $this->snapshot = true;

        return $this;
    }

    /**
     * Sorts the results by given fields
     * @link http://www.php.net/manual/en/mongocursor.sort.php
     * @param array $fields An array of fields by which to sort. Each element in the array has as key the field name, and as value either 1 for ascending sort, or -1 for descending sort
     * @throws MongoCursorException
     * @return MongoCursor Returns the same cursor that this method was called on
     */
    public function sort(array $fields)
    {
        $this->errorIfOpened();
        $this->sort = $fields;

        return $this;
    }

    /**
     * Sets whether this cursor will be left open after fetching the last results
     * @link http://www.php.net/manual/en/mongocursor.tailable.php
     * @param bool $tail If the cursor should be tailable.
     * @return MongoCursor Returns this cursor
     */
    public function tailable($tail = true)
    {
        $this->errorIfOpened();
        $this->tailable = $tail;

        return $this;
    }

    /**
     * Sets a client-side timeout for this query
     * @link http://www.php.net/manual/en/mongocursor.timeout.php
     * @param int $ms The number of milliseconds for the cursor to wait for a response. By default, the cursor will wait forever.
     * @throws MongoCursorTimeoutException
     * @return MongoCursor Returns this cursor
     */
    public function timeout($ms)
    {
        $this->notImplemented();
    }

    /**
     * Checks if the cursor is reading a valid result.
     * @link http://www.php.net/manual/en/mongocursor.valid.php
     * @return boolean If the current result is not null.
     */
    public function valid()
    {
        return $this->ensureIterator()->valid();
    }

    /**
     * Applies all options set on the cursor, overwriting any options that have already been set
     *
     * @param array $options Existing options array
     * @param array $optionNames Array of option names to be applied (will be read from properties)
     * @return array
     */
    private function applyOptions($options, $optionNames = null)
    {
        if ($optionNames === null) {
            $optionNames = [
                'allowPartialResults',
                'batchSize',
                'cursorType',
                'limit',
                'maxTimeMS',
                'modifiers',
                'noCursorTimeout',
                'oplogReplay',
                'projection',
                'readPreference',
                'skip',
                'sort',
            ];
        }

        foreach ($optionNames as $option) {
            $converter = 'convert' . ucfirst($option);
            $value = method_exists($this, $converter) ? $this->$converter() : $this->$option;

            if ($value === null) {
                continue;
            }

            $options[$option] = $value;
        }

        return $options;
    }

    /**
     * @return int|null
     */
    private function convertCursorType()
    {
        if (! $this->tailable) {
            return null;
        }

        return $this->awaitData ? Find::TAILABLE_AWAIT : Find::TAILABLE;
    }

    private function convertModifiers()
    {
        $modifiers = array_key_exists('modifiers', $this->options) ? $this->options['modifiers'] : [];

        foreach (['hint', 'snapshot'] as $modifier) {
            if ($this->$modifier === null) {
                continue;
            }

            $modifiers['$' . $modifier] = $this->$modifier;
        }

        return $modifiers;
    }

    /**
     * @return ReadPreference|null
     */
    private function convertReadPreference()
    {
        $type = array_key_exists('type', $this->readPreference) ? $this->readPreference['type'] : null;
        if ($type === null) {
            return static::$slaveOkay ? new ReadPreference(ReadPreference::RP_SECONDARY_PREFERRED) : null;
        }

        switch ($type) {
            case MongoClient::RP_PRIMARY_PREFERRED:
                $mode = ReadPreference::RP_PRIMARY_PREFERRED;
                break;
            case MongoClient::RP_SECONDARY:
                $mode = ReadPreference::RP_SECONDARY;
                break;
            case MongoClient::RP_SECONDARY_PREFERRED:
                $mode = ReadPreference::RP_SECONDARY_PREFERRED;
                break;
            case MongoClient::RP_NEAREST:
                $mode = ReadPreference::RP_NEAREST;
                break;
            default:
                $mode = ReadPreference::RP_PRIMARY;
        }

        $tagSets = array_key_exists('tagsets', $this->readPreference) ? $this->readPreference['tagsets'] : [];

        return new ReadPreference($mode, $tagSets);
    }

    /**
     * @return Cursor
     */
    private function ensureCursor()
    {
        if ($this->cursor === null) {
            $this->doQuery();
        }

        return $this->cursor;
    }

    private function errorIfOpened()
    {
        if ($this->cursor === null) {
            return;
        }

        throw new MongoCursorException('cannot modify cursor after beginning iteration.');
    }

    /**
     * @return IteratorIterator
     */
    private function ensureIterator()
    {
        if ($this->iterator === null) {
            $this->iterator = new IteratorIterator($this->ensureCursor());
        }

        return $this->iterator;
    }

    protected function notImplemented()
    {
        throw new \Exception('Not implemented');
    }
}