wellrested/src/Message/Stream.php

283 lines
8.0 KiB
PHP

<?php
namespace WellRESTed\Message;
use Psr\Http\Message\StreamInterface;
class Stream implements StreamInterface
{
/** @var resource */
private $resource;
/**
* Create a new Stream passing either a stream resource handle (e.g.,
* from fopen) or a string.
*
* If $resource is a string, the Stream will open a php://temp stream,
* write the string to the stream, and use that temp resource.
*
* @param resource|string $resource A file system pointer resource or
* string
*/
public function __construct($resource)
{
if (is_resource($resource) && get_resource_type($resource) === "stream") {
$this->resource = $resource;
} elseif (is_string($resource)) {
$this->resource = fopen("php://temp", "r+");
if ($resource !== "") {
$this->write($resource);
}
} else {
throw new \InvalidArgumentException("Expected a resource handler.");
}
}
/**
* Reads all data from the stream into a string, from the beginning to end.
*
* This method will 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.
*
* @see http://php.net/manual/en/language.oop5.magic.php#object.tostring
* @return string
*/
public function __toString()
{
$string = "";
try {
rewind($this->resource);
$string = $this->getContents();
} catch (\Exception $e) {
// Silence exceptions in order to conform with PHP's string casting operations.
}
return $string;
}
/**
* Closes the stream and any underlying resources.
*
* @return void
*/
public function close()
{
fclose($this->resource);
}
/**
* Separates any underlying resources from the stream.
*
* After the stream has been detached, the stream is in an unusable state.
*
* @return resource|null Underlying file-pointer handler
*/
public function detach()
{
$stream = $this->resource;
$this->resource = null;
return $stream;
}
/**
* 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()
{
$statistics = fstat($this->resource);
return $statistics["size"] ?: null;
}
/**
* Returns the current position of the file read/write pointer
*
* @return int Position of the file pointer
* @throws \RuntimeException on error.
*/
public function tell()
{
$position = ftell($this->resource);
if ($position === false) {
// @codeCoverageIgnoreStart
throw new \RuntimeException("Unable to retrieve current position of file pointer.");
// @codeCoverageIgnoreEnd
}
return $position;
}
/**
* Returns true if the stream is at the end of the stream.
*
* @return bool
*/
public function eof()
{
return feof($this->resource);
}
/**
* Returns whether or not the stream is seekable.
*
* @return bool
*/
public function isSeekable()
{
return $this->getMetadata("seekable") == 1;
}
/**
* 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)
{
$result = -1;
if ($this->isSeekable()) {
$result = fseek($this->resource, $offset, $whence);
}
if ($result === -1) {
// @codeCoverageIgnoreStart
throw new \RuntimeException("Unable to seek to position.");
// @codeCoverageIgnoreEnd
}
}
/**
* 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()
{
$result = false;
if ($this->isSeekable()) {
$result = rewind($this->resource);
}
if ($result === false) {
// @codeCoverageIgnoreStart
throw new \RuntimeException("Unable to seek to position.");
// @codeCoverageIgnoreEnd
}
}
/**
* Returns whether or not the stream is writable.
*
* @return bool
*/
public function isWritable()
{
$mode = $this->getMetadata("mode");
return $mode[0] !== "r" || strpos($mode, "+") !== false;
}
/**
* 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)
{
$result = false;
if ($this->isWritable()) {
$result = fwrite($this->resource, $string);
}
if ($result === false) {
throw new \RuntimeException("Unable to write to stream.");
}
return $result;
}
/**
* Returns whether or not the stream is readable.
*
* @return bool
*/
public function isReadable()
{
$mode = $this->getMetadata("mode");
return strpos($mode, "r") !== false || strpos($mode, "+") !== false;
}
/**
* 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)
{
$result = false;
if ($this->isReadable()) {
$result = fread($this->resource, $length);
}
if ($result === false) {
throw new \RuntimeException("Unable to read from stream.");
}
return $result;
}
/**
* Returns the remaining contents in a string
*
* @return string
* @throws \RuntimeException if unable to read or an error occurs while
* reading.
*/
public function getContents()
{
$result = false;
if ($this->isReadable()) {
$result = stream_get_contents($this->resource);
}
if ($result === false) {
throw new \RuntimeException("Unable to read from stream.");
}
return $result;
}
/**
* 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)
{
$metadata = stream_get_meta_data($this->resource);
if ($key === null) {
return $metadata;
} else {
return $metadata[$key];
}
}
}