Puli\Repository\StreamWrapper\ResourceStreamWrapper

Complexity

Total Complexity

50

Size/Duplication

Total Lines	609
Duplicated Lines	1.31 %

Coupling/Cohesion

Components	1
Dependencies	13

Test Coverage

Coverage

89.68%

Importance

Changes	1
Bugs	1	Features	0

26 Methods

Rating	Name	Duplication	Size	Complexity
A	unregister()	0	10	2
A	dir_opendir()	0	14	1
A	dir_closedir()	0	6	1
A	dir_readdir()	0	12	2
A	dir_rewinddir()	0	6	1
A	stream_cast()	0	4	1
A	stream_close()	0	6	1
A	stream_eof()	0	6	1
A	stream_lock()	0	7	1
A	stream_read()	0	6	1
A	stream_seek()	0	6	1
A	stream_set_option()	0	4	1
A	stream_stat()	0	6	1
A	stream_tell()	0	6	1
A	stream_truncate()	0	6	1
A	stream_write()	0	6	1
B	url_stat()	0	36	5
A	mkdir()	0	8	1
A	rename()	0	14	1
A	rmdir()	0	16	2
A	stream_flush()	0	6	1
C	stream_metadata()	0	34	7
B	stream_open()	0	36	5
A	unlink()	0	8	1
B	getRepository()	8	28	5
B	register()	0	26	4

<?php

/*
 * This file is part of the puli/repository package.
 *
 * (c) Bernhard Schussek <bschussek@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Puli\Repository\StreamWrapper;

use InvalidArgumentException;
use Puli\Repository\Api\Resource\BodyResource;
use Puli\Repository\Api\Resource\FilesystemResource;
use Puli\Repository\Api\ResourceNotFoundException;
use Puli\Repository\Api\ResourceRepository;
use Puli\Repository\Api\UnsupportedOperationException;
use Puli\Repository\Api\UnsupportedResourceException;
use Puli\Repository\RepositoryFactoryException;
use Puli\Repository\Resource\Iterator\ResourceCollectionIterator;
use Puli\Repository\Uri\Uri;
use Webmozart\Assert\Assert;

/**
 * Registers a PHP stream wrapper for a {@link ResourceRepository}.
 *
 * To register the stream wrapper, call {@link register}:
 *
 * ```php
 * use Puli\Repository\InMemoryRepository;
 * use Puli\Repository\StreamWrapper\ResourceStreamWrapper;
 *
 * $repo = new InMemoryRepository();
 *
 * ResourceStreamWrapper::register('puli', $repo);
 *
 * file_get_contents('puli:///css/style.css');
 * // => $puliRepo->get('/css/style.css')->getBody()
 * ```
 *
 * The stream wrapper can only be used for reading, not writing.
 *
 * @since  1.0
 *
 * @author Bernhard Schussek <bschussek@gmail.com>
 */
class ResourceStreamWrapper implements StreamWrapper
{
    const DEVICE_ASSOC = 'dev';

    const DEVICE_NUM = 0;

    const INODE_ASSOC = 'ino';

    const INODE_NUM = 1;

    const MODE_ASSOC = 'mode';

    const MODE_NUM = 2;

    const NUM_LINKS_ASSOC = 'nlink';

    const NUM_LINK_NUM = 3;

    const UID_ASSOC = 'uid';

    const UID_NUM = 4;

    const GID_ASSOC = 'gid';

    const GID_NUM = 5;

    const DEVICE_TYPE_ASSOC = 'rdev';

    const DEVICE_TYPE_NUM = 6;

    const SIZE_ASSOC = 'size';

    const SIZE_NUM = 7;

    const ACCESS_TIME_ASSOC = 'atime';

    const ACCESS_TIME_NUM = 8;

    const MODIFY_TIME_ASSOC = 'mtime';

    const MODIFY_TIME_NUM = 9;

    const CHANGE_TIME_ASSOC = 'ctime';

    const CHANGE_TIME_NUM = 10;

    const BLOCK_SIZE_ASSOC = 'blksize';

    const BLOCK_SIZE_NUM = 11;

    const NUM_BLOCKS_ASSOC = 'blocks';

    const NUM_BLOCKS_NUM = 12;

    /**
     * @var array
     */
    private static $defaultStat = array(
        self::DEVICE_ASSOC => -1,
        self::DEVICE_NUM => -1,
        self::INODE_ASSOC => -1,
        self::INODE_NUM => -1,
        self::MODE_ASSOC => -1,
        self::MODE_NUM => -1,
        self::NUM_LINKS_ASSOC => -1,
        self::NUM_LINK_NUM => -1,
        self::UID_ASSOC => 0,
        self::UID_NUM => 0,
        self::GID_ASSOC => 0,
        self::GID_NUM => 0,
        self::DEVICE_TYPE_ASSOC => -1,
        self::DEVICE_TYPE_NUM => -1,
        self::SIZE_ASSOC => 0,
        self::SIZE_NUM => 0,
        self::ACCESS_TIME_ASSOC => -1,
        self::ACCESS_TIME_NUM => -1,
        self::MODIFY_TIME_ASSOC => -1,
        self::MODIFY_TIME_NUM => -1,
        self::CHANGE_TIME_ASSOC => -1,
        self::CHANGE_TIME_NUM => -1,
        self::BLOCK_SIZE_ASSOC => -1,
        self::BLOCK_SIZE_NUM => -1,
        self::NUM_BLOCKS_ASSOC => 0,
        self::NUM_BLOCKS_NUM => 0,
    );

    /**
     * @var ResourceRepository[]|callable[]
     */
    private static $repos;

    /**
     * @var resource
     */
    private $handle;

    /**
     * @var ResourceCollectionIterator
     */
    private $childIterator;

    /**
     * Registers a repository as PHP stream wrapper.
     *
     * The resources of the repository can subsequently be accessed with PHP's
     * file system by prefixing the resource paths with the registered URI
     * scheme:
     *
     * ```php
     * ResourceStreamWrapper::register('puli', $repo);
     *
     * // /app/css/style.css
     * $contents = file_get_contents('puli:///app/css/style.css');
     * ```
     *
     * Instead of passing a repository, you can also pass a callable. The
     * callable is executed when the repository is accessed for the first time
     * and should return a valid {@link ResourceRepository} instance.
     *
     * @param string                      $scheme            The URI scheme.
     * @param ResourceRepository|callable $repositoryFactory The repository to use.
     *
     * @throws StreamWrapperException If a repository was previously registered
     *                                for the same scheme. Call
     *                                {@link unregister()} to unregister the
     *                                scheme first.
     */
    public static function register($scheme, $repositoryFactory)
    {
        if (!$repositoryFactory instanceof ResourceRepository
                && !is_callable($repositoryFactory)) {
            throw new InvalidArgumentException(sprintf(
                'The repository factory should be a callable or an instance '.
                'of ResourceRepository. Got: %s',
                $repositoryFactory
            ));
        }

        Assert::string($scheme, 'The scheme must be a string. Got: %s');
        Assert::alnum($scheme, 'The scheme %s should consist of letters and digits only.');
        Assert::startsWithLetter($scheme, 'The scheme %s should start with a letter.');

        if (isset(self::$repos[$scheme])) {
            throw new StreamWrapperException(sprintf(
                'The scheme "%s" has already been registered.',
                $scheme
            ));
        }

        self::$repos[$scheme] = $repositoryFactory;

        stream_wrapper_register($scheme, __CLASS__);
    }

    /**
     * Unregisters the given scheme.
     *
     * Unknown schemes are ignored.
     *
     * @param string $scheme A URI scheme.
     */
    public static function unregister($scheme)
    {
        if (!isset(self::$repos[$scheme])) {
            return;
        }

        unset(self::$repos[$scheme]);

        stream_wrapper_unregister($scheme);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function dir_opendir($uri, $options)
    {
        $parts = Uri::parse($uri);

        // Provoke ResourceNotFoundException if not found
        $resource = $this->getRepository($parts['scheme'])->get($parts['path']);

        $this->childIterator = new ResourceCollectionIterator(
            $resource->listChildren(),
            ResourceCollectionIterator::CURRENT_AS_NAME
        );

        return true;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function dir_closedir()
    {
        $this->childIterator = null;

        return false;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function dir_readdir()
    {
        if (!$this->childIterator->valid()) {
            return false;
        }

        $name = $this->childIterator->current();

        $this->childIterator->next();

        return $name;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function dir_rewinddir()
    {
        $this->childIterator->rewind();

        return true;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function mkdir($uri, $mode, $options)
    {
        throw new UnsupportedOperationException(sprintf(
            'The creation of new directories through the stream wrapper is '.
            'not supported. Tried to create the directory "%s".',
            $uri
        ));
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function rename($uriFrom, $uriTo)
    {
        $parts = Uri::parse($uriFrom);

        // validate whether the URL exists
        $this->getRepository($parts['scheme'])->get($parts['path']);

        throw new UnsupportedOperationException(sprintf(
            'The renaming of resources through the stream wrapper is not '.
            'supported. Tried to rename "%s" to "%s".',
            $uriFrom,
            $uriTo
        ));
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function rmdir($uri, $options)
    {
        $parts = Uri::parse($uri);

        // validate whether the URL exists
        $resource = $this->getRepository($parts['scheme'])->get($parts['path']);

        throw new UnsupportedOperationException(sprintf(
            'The removal of directories through the stream wrapper is not '.
            'supported. Tried to remove "%s"%s.',
            $uri,
            $resource instanceof FilesystemResource
                ? sprintf(' which points to "%s"', $resource->getFilesystemPath())
                : ''
        ));
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_cast($castAs)
    {
        return $this->handle;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_close()
    {
        assert(null !== $this->handle);

        return fclose($this->handle);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_eof()
    {
        assert(null !== $this->handle);

        return feof($this->handle);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_flush()
    {
        assert(null !== $this->handle);

        return fflush($this->handle);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_lock($operation)
    {
        throw new UnsupportedOperationException(
            'The locking of files through the stream wrapper is not '.
            'supported.'
        );
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_metadata($uri, $option)
    {
        switch ($option) {
            case STREAM_META_TOUCH:
                throw new UnsupportedOperationException(sprintf(
                    'Touching files through the stream wrapper is not '.
                    'supported. Tried to touch "%s".',
                    $uri
                ));

            case STREAM_META_OWNER:
            case STREAM_META_OWNER_NAME:
                throw new UnsupportedOperationException(sprintf(
                    'Changing file ownership through the stream wrapper '.
                    'is not supported. Tried to chown "%s".',
                    $uri
                ));

            case STREAM_META_GROUP:
            case STREAM_META_GROUP_NAME:
                throw new UnsupportedOperationException(sprintf(
                    'Changing file groups through the stream wrapper '.
                    'is not supported. Tried to chgrp "%s".',
                    $uri
                ));

            case STREAM_META_ACCESS:
                throw new UnsupportedOperationException(sprintf(
                    'Changing file permissions through the stream wrapper '.
                    'is not supported. Tried to chmod "%s".',
                    $uri
                ));
        }
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_open($uri, $mode, $options, &$openedPath)
    {
        if (!preg_match('/^[rbt]+$/', $mode)) {
            throw new UnsupportedOperationException(sprintf(
                'Resources can only be opened for reading. Tried to open "%s" '.
                'with mode "%s".',
                $uri,
                $mode
            ));
        }

        $parts = Uri::parse($uri);

        $resource = $this->getRepository($parts['scheme'])->get($parts['path']);

        if (!$resource instanceof BodyResource) {
            throw new UnsupportedResourceException(sprintf(
                'Can only open file resources for reading. Tried to open "%s" '.
                'of type %s which does not implement BodyResource.',
                $uri,
                get_class($resource)
            ));
        }

        if ($resource instanceof FilesystemResource) {
            $this->handle = fopen($resource->getFilesystemPath(), 'r', $options & STREAM_USE_PATH) ?: null;

            return null !== $this->handle;
        }

        $this->handle = fopen('php://temp', 'r+', $options & STREAM_USE_PATH);
        fwrite($this->handle, $resource->getBody());
        rewind($this->handle);

        return true;
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_read($length)
    {
        assert(null !== $this->handle);

        return fread($this->handle, $length);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_seek($offset, $whence = SEEK_SET)
    {
        assert(null !== $this->handle);

        return 0 === fseek($this->handle, $offset, $whence);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_set_option($option, $arg1, $arg2)
    {
        // noop
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_stat()
    {
        assert(null !== $this->handle);

        return fstat($this->handle);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_tell()
    {
        assert(null !== $this->handle);

        return ftell($this->handle);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_truncate($newSize)
    {
        assert(null !== $this->handle);

        return ftruncate($this->handle, $newSize);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function stream_write($data)
    {
        assert(null !== $this->handle);

        return fwrite($this->handle, $data);
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function unlink($uri)
    {
        throw new UnsupportedOperationException(sprintf(
            'The removal of files through the stream wrapper is not '.
            'supported. Tried to remove "%s".',
            $uri
        ));
    }

    /**
     * {@inheritdoc}
     *
     * @internal
     */
    public function url_stat($uri, $flags)
    {
        try {
            $parts = Uri::parse($uri);

            $resource = $this->getRepository($parts['scheme'])->get($parts['path']);

            if ($resource instanceof FilesystemResource) {
                $path = $resource->getFilesystemPath();

                if ($flags & STREAM_URL_STAT_LINK) {
                    return lstat($path);
                }

                return stat($path);
            }

            $stat = self::$defaultStat;

            $metadata = $resource->getMetadata();

            $stat[self::SIZE_NUM] = $stat[self::SIZE_ASSOC] = $metadata->getSize();
            $stat[self::ACCESS_TIME_NUM] = $stat[self::ACCESS_TIME_ASSOC] = $metadata->getAccessTime();
            $stat[self::MODIFY_TIME_NUM] = $stat[self::MODIFY_TIME_ASSOC] = $metadata->getModificationTime();

            return $stat;
        } catch (ResourceNotFoundException $e) {
            if ($flags & STREAM_URL_STAT_QUIET) {
                // Same result as stat() returns on error
                // file_exists() returns false for this resource
                return false;
            }

            throw $e;
        }
    }

    /**
     * Constructs (if necessary) and returns the repository for the given scheme.
     *
     * @param string $scheme A URI scheme.
     *
     * @return ResourceRepository The resource repository.
     *
     * @throws RepositoryFactoryException If the callable did not return an
     *                                    instance of {@link ResourceRepository}.
     * @throws StreamWrapperException     If the scheme is not supported.
     */
    private function getRepository($scheme)
    {
        if (!isset(self::$repos[$scheme])) {
            throw new StreamWrapperException(sprintf(
                'The stream wrapper has not been registered for the scheme "%s". '.
                'Please call ResourceStreamWrapper::register() first.',
                $scheme
            ));
        }

        if (is_callable(self::$repos[$scheme])) {
            $callable = self::$repos[$scheme];
            $result = $callable($scheme);

            if (!$result instanceof ResourceRepository) {
                throw new RepositoryFactoryException(sprintf(
                    'The repository factory registered for scheme "%s" should '.
                    'return a ResourceRepository instance. Got: %s',
                    $scheme,
                    is_object($result) ? get_class($result) : gettype($result)
                ));
            }

            self::$repos[$scheme] = $result;
        }

        return self::$repos[$scheme];
    }
}