Kambo\Http\Message\Stream

Complexity

Total Complexity

36

Size/Duplication

Total Lines	300
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	0

Test Coverage

Coverage

100%

Importance

Changes

0

16 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	4	1
A	close()	0	8	2
A	detach()	0	10	1
A	getSize()	0	9	4
A	tell()	0	8	3
A	eof()	0	4	2
A	isSeekable()	0	4	1
A	seek()	0	6	3
A	rewind()	0	4	1
A	isWritable()	0	5	1
A	write()	0	11	3
A	isReadable()	0	5	1
A	read()	0	8	3
A	getContents()	0	8	3
A	getMetadata()	0	11	4
A	__toString()	0	13	3

<?php
namespace Kambo\Http\Message;

// \Spl
use RuntimeException;

// \Psr
use Psr\Http\Message\StreamInterface;

/**
 * Describes a data stream.
 *
 * It provides a wrapper around the most common operations, including serialization of
 * the entire stream to a string.
 *
 * @package Kambo\Http\Message
 * @author  Bohuslav Simek <bohuslav@simek.si>
 * @license MIT
 */
class Stream implements StreamInterface
{
    /**
     * Underline stream
     *
     * @var Resource|null
     */
    private $stream = null;

    /**
     * Size of file
     *
     * @var int|null
     */
    private $size = null;

    /**
     * Metadata of file
     *
     * @var array|null
     */
    private $meta = null;

    /**
     * Resource modes
     *
     * @var  array
     * @link http://php.net/manual/function.fopen.php
     */
    private $modes = [
        'readable' => ['r', 'r+', 'w+', 'a+', 'x+', 'c+', 'w+b'],
        'writable' => ['r+', 'w', 'w+', 'a', 'a+', 'x', 'x+', 'c', 'c+', 'w+b'],
    ];

    /**
     * Constructor
     *
     * @param Resource $stream Underline resource stream
     */
    public function __construct($stream)
    {
        $this->stream = $stream;
    }

    /**
     * Closes the stream and any underlying resources.
     *
     * @return void
     */
    public function close()
    {
        if ($this->stream !== null) {
            fclose($this->stream);
        }

        $this->detach();
    }

    /**
     * Separates any underlying resources from the stream.
     *
     * After the stream has been detached, the stream is in an unusable state.
     *
     * @return resource|null Underlying PHP stream, if any
     */
    public function detach()
    {
        $oldStream = $this->stream;

        $this->stream = null;
        $this->size   = null;
        $this->meta   = null;

        return $oldStream;
    }

    /**
     * Get the size of the stream if known.
     *
     * @return int|null Returns the size in bytes if known, or null if unknown.
     */
    public function getSize()
    {
        if ($this->stream !== null && $this->size === null) {
            $stats = fstat($this->stream);
            $this->size = isset($stats['size']) ? $stats['size'] : null;
        }

        return $this->size;
    }

    /**
     * Returns the current position of the file read/write pointer
     *
     * @return int Position of the file pointer
     *
     * @throws \RuntimeException on error.
     */
    public function tell()
    {
        if ($this->stream === null || ($position = ftell($this->stream)) === false) {
            throw new RuntimeException('Could not get the position of the pointer in stream');
        }

        return $position;
    }

    /**
     * Returns true if the stream is at the end of the stream.
     *
     * @return bool
     */
    public function eof()
    {
        return $this->stream !== null ? feof($this->stream) : true;
    }

    /**
     * Returns whether or not the stream is seekable.
     *
     * @return bool 
     */
    public function isSeekable()
    {
        return $this->getMetadata('seekable');
    }

    /**
     * Seek to a position in the stream.
     *
     * @link http://www.php.net/manual/en/function.fseek.php
     *
     * @param int $offset Stream offset
     * @param int $whence Specifies how the cursor position will be calculated
     *                    based on the seek offset. Valid values are identical to the built-in
     *                    PHP $whence values for `fseek()`.  SEEK_SET: Set position equal to
     *                    offset bytes SEEK_CUR: Set position to current location plus offset
     *                    SEEK_END: Set position to end-of-stream plus offset.
     *
     * @throws \RuntimeException on failure.
     */
    public function seek($offset, $whence = SEEK_SET)
    {
        if (!$this->isSeekable() || fseek($this->stream, $offset, $whence) === -1) {
            throw new RuntimeException('Could not seek in stream');
        }
    }

    /**
     * Seek to the beginning of the stream.
     *
     * If the stream is not seekable, this method will raise an exception;
     * otherwise, it will perform a seek(0).
     *
     * @see seek()
     * @link http://www.php.net/manual/en/function.fseek.php
     *
     * @throws \RuntimeException on failure.
     */
    public function rewind()
    {
        $this->seek(0);
    }

    /**
     * Returns whether or not the stream is writable.
     *
     * @return bool
     */
    public function isWritable()
    {
        $fileMode = $this->getMetadata('mode');
        return (in_array($fileMode, $this->modes['writable']));
    }

    /**
     * Write data to the stream.
     *
     * @param string $string The string that is to be written.
     *
     * @return int Returns the number of bytes written to the stream.
     *
     * @throws \RuntimeException on failure.
     */
    public function write($string)
    {
        if (!$this->isWritable() || ($written = fwrite($this->stream, $string)) === false) {
            throw new RuntimeException('Could not write to stream');
        }

        // clear size
        $this->size = null;

        return $written;
    }

    /**
     * Returns whether or not the stream is readable.
     *
     * @return bool
     */
    public function isReadable()
    {
        $fileMode = $this->getMetadata('mode');
        return (in_array($fileMode, $this->modes['readable']));
    }

    /**
     * Read data from the stream.
     *
     * @param int $length Read up to $length bytes from the object and return
     *                    them. Fewer than $length bytes may be returned if underlying stream
     *                    call returns fewer bytes.
     *
     * @return string Returns the data read from the stream, or an empty string
     *     if no bytes are available.
     *
     * @throws \RuntimeException if an error occurs.
     */
    public function read($length)
    {
        if (!$this->isReadable() || ($data = fread($this->stream, $length)) === false) {
            throw new RuntimeException('Could not read from stream');
        }

        return $data;
    }

    /**
     * Returns the remaining contents in a string
     *
     * @return string
     *
     * @throws \RuntimeException if unable to read or an error occurs while reading.
     */
    public function getContents()
    {
        if (!$this->isReadable() || ($contents = stream_get_contents($this->stream)) === false) {
            throw new RuntimeException('Could not get contents of stream');
        }

        return $contents;
    }

    /**
     * Get stream metadata as an associative array or retrieve a specific key.
     *
     * The keys returned are identical to the keys returned from PHP's
     * stream_get_meta_data() function.
     *
     * @link http://php.net/manual/en/function.stream-get-meta-data.php
     *
     * @param string $key Specific metadata to retrieve.
     *
     * @return array|mixed|null Returns an associative array if no key is provided.
     *                          Returns a specific key value if a key is provided and the
     *                          value is found, or null if the key is not found.
     */
    public function getMetadata($key = null)
    {
        if (isset($this->stream)) {
            $this->meta = stream_get_meta_data($this->stream);
            if (is_null($key) === true) {
                return $this->meta;
            }
        }

        return isset($this->meta[$key]) ? $this->meta[$key] : null;
    }


    /**
     * Reads all data from the stream into a string, from the beginning to end.
     *
     * This method attempt to seek to the beginning of the stream before
     * reading data and read the stream until the end is reached.
     *
     * Warning: This could attempt to load a large amount of data into memory.
     *
     * This method does not raise an exception in order to conform with PHP's
     * string casting operations.
     *
     * @see http://php.net/manual/en/language.oop5.magic.php#object.tostring
     *
     * @return string
     */
    public function __toString()
    {
        if ($this->stream === null) {
            return '';
        }

        try {
            $this->rewind();
            return $this->getContents();
        } catch (RuntimeException $e) {
            return '';
        }
    }
}