abstract class AbstractSerializer in Zircon Profile 8

Provides base functionality for request and response de/serialization strategies, including functionality for retrieving a line at a time from the message, splitting headers from the body, and serializing headers.

Hierarchy

• class \Zend\Diactoros\AbstractSerializer

2 files declare their use of AbstractSerializer

Serializer.php in vendor/zendframework/zend-diactoros/src/Request/Serializer.php

Serializer.php in vendor/zendframework/zend-diactoros/src/Response/Serializer.php

File

vendor/zendframework/zend-diactoros/src/AbstractSerializer.php, line 20

Namespace

Zend\Diactoros

abstract class AbstractSerializer {
  const CR = "\r";
  const EOL = "\r\n";
  const LF = "\n";

  /**
   * Retrieve a single line from the stream.
   *
   * Retrieves a line from the stream; a line is defined as a sequence of
   * characters ending in a CRLF sequence.
   *
   * @param StreamInterface $stream
   * @return string
   * @throws UnexpectedValueException if the sequence contains a CR or LF in
   *     isolation, or ends in a CR.
   */
  protected static function getLine(StreamInterface $stream) {
    $line = '';
    $crFound = false;
    while (!$stream
      ->eof()) {
      $char = $stream
        ->read(1);
      if ($crFound && $char === self::LF) {
        $crFound = false;
        break;
      }

      // CR NOT followed by LF
      if ($crFound && $char !== self::LF) {
        throw new UnexpectedValueException('Unexpected carriage return detected');
      }

      // LF in isolation
      if (!$crFound && $char === self::LF) {
        throw new UnexpectedValueException('Unexpected line feed detected');
      }

      // CR found; do not append
      if ($char === self::CR) {
        $crFound = true;
        continue;
      }

      // Any other character: append
      $line .= $char;
    }

    // CR found at end of stream
    if ($crFound) {
      throw new UnexpectedValueException("Unexpected end of headers");
    }
    return $line;
  }

  /**
   * Split the stream into headers and body content.
   *
   * Returns an array containing two elements
   *
   * - The first is an array of headers
   * - The second is a StreamInterface containing the body content
   *
   * @param StreamInterface $stream
   * @return array
   * @throws UnexpectedValueException For invalid headers.
   */
  protected static function splitStream(StreamInterface $stream) {
    $headers = [];
    $currentHeader = false;
    while ($line = self::getLine($stream)) {
      if (preg_match(';^(?P<name>[!#$%&\'*+.^_`\\|~0-9a-zA-Z-]+):(?P<value>.*)$;', $line, $matches)) {
        $currentHeader = $matches['name'];
        if (!isset($headers[$currentHeader])) {
          $headers[$currentHeader] = [];
        }
        $headers[$currentHeader][] = ltrim($matches['value']);
        continue;
      }
      if (!$currentHeader) {
        throw new UnexpectedValueException('Invalid header detected');
      }
      if (!preg_match('#^[ \\t]#', $line)) {
        throw new UnexpectedValueException('Invalid header continuation');
      }

      // Append continuation to last header value found
      $value = array_pop($headers[$currentHeader]);
      $headers[$currentHeader][] = $value . ltrim($line);
    }

    // use RelativeStream to avoid copying initial stream into memory
    return [
      $headers,
      new RelativeStream($stream, $stream
        ->tell()),
    ];
  }

  /**
   * Serialize headers to string values.
   *
   * @param array $headers
   * @return string
   */
  protected static function serializeHeaders(array $headers) {
    $lines = [];
    foreach ($headers as $header => $values) {
      $normalized = self::filterHeader($header);
      foreach ($values as $value) {
        $lines[] = sprintf('%s: %s', $normalized, $value);
      }
    }
    return implode("\r\n", $lines);
  }

  /**
   * Filter a header name to wordcase
   *
   * @param string $header
   * @return string
   */
  protected static function filterHeader($header) {
    $filtered = str_replace('-', ' ', $header);
    $filtered = ucwords($filtered);
    return str_replace(' ', '-', $filtered);
  }

}

Members

Name	Modifiers	Type	Description	Overrides
AbstractSerializer::CR		constant
AbstractSerializer::EOL		constant
AbstractSerializer::filterHeader	protected static	function	Filter a header name to wordcase
AbstractSerializer::getLine	protected static	function	Retrieve a single line from the stream.
AbstractSerializer::LF		constant
AbstractSerializer::serializeHeaders	protected static	function	Serialize headers to string values.
AbstractSerializer::splitStream	protected static	function	Split the stream into headers and body content.