[Summary view]

   1  <?php
   2  
   3  namespace Psr\Http\Message;
   4  
   5  /**
   6   * Describes a data stream.
   7   *
   8   * Typically, an instance will wrap a PHP stream; this interface provides
   9   * a wrapper around the most common operations, including serialization of
  10   * the entire stream to a string.
  11   */
  12  interface StreamInterface
  13  {
  14      /**
  15       * Reads all data from the stream into a string, from the beginning to end.
  16       *
  17       * This method MUST attempt to seek to the beginning of the stream before
  18       * reading data and read the stream until the end is reached.
  19       *
  20       * Warning: This could attempt to load a large amount of data into memory.
  21       *
  22       * This method MUST NOT raise an exception in order to conform with PHP's
  23       * string casting operations.
  24       *
  25       * @see http://php.net/manual/en/language.oop5.magic.php#object.tostring
  26       * @return string
  27       */
  28      public function __toString();
  29  
  30      /**
  31       * Closes the stream and any underlying resources.
  32       *
  33       * @return void
  34       */
  35      public function close();
  36  
  37      /**
  38       * Separates any underlying resources from the stream.
  39       *
  40       * After the stream has been detached, the stream is in an unusable state.
  41       *
  42       * @return resource|null Underlying PHP stream, if any
  43       */
  44      public function detach();
  45  
  46      /**
  47       * Get the size of the stream if known.
  48       *
  49       * @return int|null Returns the size in bytes if known, or null if unknown.
  50       */
  51      public function getSize();
  52  
  53      /**
  54       * Returns the current position of the file read/write pointer
  55       *
  56       * @return int Position of the file pointer
  57       * @throws \RuntimeException on error.
  58       */
  59      public function tell();
  60  
  61      /**
  62       * Returns true if the stream is at the end of the stream.
  63       *
  64       * @return bool
  65       */
  66      public function eof();
  67  
  68      /**
  69       * Returns whether or not the stream is seekable.
  70       *
  71       * @return bool
  72       */
  73      public function isSeekable();
  74  
  75      /**
  76       * Seek to a position in the stream.
  77       *
  78       * @link http://www.php.net/manual/en/function.fseek.php
  79       * @param int $offset Stream offset
  80       * @param int $whence Specifies how the cursor position will be calculated
  81       *     based on the seek offset. Valid values are identical to the built-in
  82       *     PHP $whence values for `fseek()`.  SEEK_SET: Set position equal to
  83       *     offset bytes SEEK_CUR: Set position to current location plus offset
  84       *     SEEK_END: Set position to end-of-stream plus offset.
  85       * @throws \RuntimeException on failure.
  86       */
  87      public function seek($offset, $whence = SEEK_SET);
  88  
  89      /**
  90       * Seek to the beginning of the stream.
  91       *
  92       * If the stream is not seekable, this method will raise an exception;
  93       * otherwise, it will perform a seek(0).
  94       *
  95       * @see seek()
  96       * @link http://www.php.net/manual/en/function.fseek.php
  97       * @throws \RuntimeException on failure.
  98       */
  99      public function rewind();
 100  
 101      /**
 102       * Returns whether or not the stream is writable.
 103       *
 104       * @return bool
 105       */
 106      public function isWritable();
 107  
 108      /**
 109       * Write data to the stream.
 110       *
 111       * @param string $string The string that is to be written.
 112       * @return int Returns the number of bytes written to the stream.
 113       * @throws \RuntimeException on failure.
 114       */
 115      public function write($string);
 116  
 117      /**
 118       * Returns whether or not the stream is readable.
 119       *
 120       * @return bool
 121       */
 122      public function isReadable();
 123  
 124      /**
 125       * Read data from the stream.
 126       *
 127       * @param int $length Read up to $length bytes from the object and return
 128       *     them. Fewer than $length bytes may be returned if underlying stream
 129       *     call returns fewer bytes.
 130       * @return string Returns the data read from the stream, or an empty string
 131       *     if no bytes are available.
 132       * @throws \RuntimeException if an error occurs.
 133       */
 134      public function read($length);
 135  
 136      /**
 137       * Returns the remaining contents in a string
 138       *
 139       * @return string
 140       * @throws \RuntimeException if unable to read or an error occurs while
 141       *     reading.
 142       */
 143      public function getContents();
 144  
 145      /**
 146       * Get stream metadata as an associative array or retrieve a specific key.
 147       *
 148       * The keys returned are identical to the keys returned from PHP's
 149       * stream_get_meta_data() function.
 150       *
 151       * @link http://php.net/manual/en/function.stream-get-meta-data.php
 152       * @param string $key Specific metadata to retrieve.
 153       * @return array|mixed|null Returns an associative array if no key is
 154       *     provided. Returns a specific key value if a key is provided and the
 155       *     value is found, or null if the key is not found.
 156       */
 157      public function getMetadata($key = null);
 158  }