Implements: Countable | Serializable | ArrayAccess | Traversable | IteratorAggregate
The Kohana_HTTP_Header class provides an Object-Orientated interface
to HTTP headers. This can parse header arrays returned from the
PHP functions apache_request_headers() or the http_parse_headers()
function available within the PECL HTTP library.
Class declared in SYSPATH/classes/kohana/http/header.php on line 15.
integer 1
integer 2
array $default_sort_filterDefault positive filter for sorting header values
array(4) ( 0 => string(6) "accept" 1 => string(14) "accept-charset" 2 => string(15) "accept-encoding" 3 => string(15) "accept-language" )
boolean $sort_by_qualityControls whether to automatically sort headers by quality value
bool FALSE
Constructor method for Kohana_HTTP_Header. Uses the standard constructor
of the parent ArrayObject class.
$header_object = new HTTP_Header(array('x-powered-by' => 'Kohana 3.1.x', 'expires' => '...'));
mixed
$input
required - Input arrayint
$flags
= NULL - Flagsstring
$iterator_class
= string(13) "ArrayIterator" - The iterator class to usepublic function __construct($input, $flags = NULL, $iterator_class = 'ArrayIterator')
{
// Parse the values into [HTTP_Header_Values]
parent::__construct(HTTP_Header::parse_header_values($input), $flags, $iterator_class);
// If sort by quality is set, sort the fields by q=0.0 value
if (HTTP_Header::$sort_by_quality)
{
$this->sort_values_by_quality();
}
}Returns the header object as a string, including the terminating new line
// Return the header as a string
echo (string) $request->headers();
stringpublic function __toString()
{
$header = '';
foreach ($this as $key => $value)
{
if (is_array($value))
{
$header .= $key.': '.(implode(', ', $value))."\r\n";
}
else
{
$header .= $key.': '.$value."\r\n";
}
}
return $header."\n";
}Overloads the ArrayObject::exchangeArray() method to ensure all
values passed are parsed correctly into a Kohana_HTTP_Header_Value.
// Input new headers
$headers->exchangeArray(array(
'date' => 'Wed, 24 Nov 2010 21:09:23 GMT',
'cache-control' => 'no-store, no-cache, must-revalidate, post-check=0, pre-check=0'
));
array
$array
required - Array to exchangearraypublic function exchangeArray($array)
{
return parent::exchangeArray(HTTP_Header::parse_header_values($array));
}Overloads the ArrayObject::offsetSet method to ensure any
access is correctly converted to the correct object type.
// Add a new header from encoded string
$headers['cache-control'] = 'no-store, no-cache, must-revalidate, post-check=0, pre-check=0'
mixed
$index
required - Keymixed
$newval
required - Valuevoidpublic function offsetSet($index, $newval)
{
if (is_array($newval) AND (current($newval) instanceof HTTP_Header_Value))
return parent::offsetSet(strtolower($index), $newval);
elseif ( ! $newval instanceof HTTP_Header_Value)
{
$newval = new HTTP_Header_Value((string) $newval);
}
parent::offsetSet(strtolower($index), (string) $newval);
}Parses HTTP Header values and creating an appropriate object depending on type; i.e. accept-type, accept-char, cache-control etc.
$header_values_array = HTTP_Header::parse_header_values(array('cache-control' => 'max-age=200; public'));
array
$header_values
required - Values to parsearray
$header_commas_allowed
= array(4) (
0 => string(10) "user-agent"
1 => string(4) "date"
2 => string(7) "expires"
3 => string(13) "last-modified"
) - Header values where commas are not delimiters (usually date)arraypublic static function parse_header_values(array $header_values, array $header_commas_allowed = array('user-agent', 'date', 'expires', 'last-modified'))
{
/**
* @see http://www.w3.org/Protocols/rfc2616/rfc2616.html
*
* HTTP header declarations should be treated as case-insensitive
*/
$header_values = array_change_key_case($header_values, CASE_LOWER);
// Foreach of the header values applied
foreach ($header_values as $key => $value)
{
if (is_array($value))
{
$values = array();
if (Arr::is_assoc($value))
{
foreach ($value as $k => $v)
{
$values[] = HTTP_Header::parse_header_values($v);
}
}
else
{
// RFC 2616 allows multiple headers with same name if they can be
// concatinated using commas without altering the original message.
// This usually occurs with multiple Set-Cookie: headers
$array = array();
foreach ($value as $k => $v)
{
// Break value into component parts
$v = explode(';', $v);
// Do some nasty parsing to flattern the array into components,
// parsing key values
$array = Arr::flatten(array_map('HTTP_Header_Value::parse_key_value', $v));
// Get the K/V component and extract the first element
$key_value_component = array_slice($array, 0, 1, TRUE);
array_shift($array);
// Create the HTTP_Header_Value component array
$http_header['key'] = key($key_value_component);
$http_header['value'] = current($key_value_component);
$http_header['properties'] = $array;
// Create the HTTP_Header_Value
$values[] = new HTTP_Header_Value($http_header);
}
}
// Assign HTTP_Header_Value array to the header
$header_values[$key] = $values;
continue;
}
// If the key allows commas or no commas are found
if (in_array($key, $header_commas_allowed) or (strpos($value, ',') === FALSE))
{
// If the key is user-agent, we don't want to parse the string
if ($key === 'user-agent')
{
$header_values[$key] = new HTTP_Header_Value($value, TRUE);
}
// Else, behave normally
else
{
$header_values[$key] = new HTTP_Header_Value($value);
}
// Move to next header
continue;
}
// Create an array of the values and clear any whitespace
$value = array_map('trim', explode(',', $value));
$parsed_values = array();
// Foreach value
foreach ($value as $v)
{
$v = new HTTP_Header_Value($v);
// Convert the value string into an object
if ($v->key === NULL)
{
$parsed_values[] = $v;
}
else
{
$parsed_values[$v->key] = $v;
}
}
// Apply parsed value to the header
$header_values[$key] = $parsed_values;
}
// Return the parsed header values
return $header_values;
}Sort the headers by quality property if the header matches the Kohana_HTTP_Header::$default_sort_filter definition.
array
$filter
= array(0) - Header fields to parseselfpublic function sort_values_by_quality(array $filter = array())
{
// If a filter argument is supplied
if ($filter)
{
// Apply filter and store previous
$previous_filter = HTTP_Header::$default_sort_filter;
HTTP_Header::$default_sort_filter = $filter;
}
// Get a copy of this ArrayObject
$values = $this->getArrayCopy();
foreach ($values as $key => $value)
{
if ( ! is_array($value) or ! in_array($key, HTTP_Header::$default_sort_filter))
{
unset($values[$key]);
continue;
}
// Sort them by comparison
uasort($value, array($this, '_sort_by_comparison'));
$values[$key] = $value;
}
// Return filter to previous state if required
if ($filter)
{
HTTP_Header::$default_sort_filter = $previous_filter;
}
foreach ($values as $key => $value)
{
$this[$key] = $value;
}
// Return this
return $this;
}protected function _sort_by_comparison($value_a, $value_b)
{
// Test for correct instance type
if ( ! $value_a instanceof HTTP_Header_Value OR ! $value_b instanceof HTTP_Header_Value)
{
// Return neutral if cannot test value
return 0;
}
// Extract the qualities
$a = (float) Arr::get($value_a->properties, 'q', HTTP_Header_Value::$default_quality);
$b = (float) Arr::get($value_b->properties, 'q', HTTP_Header_Value::$default_quality);
if ($a == $b)
return 0;
elseif ($a < $b)
return 1;
elseif ($a > $b)
return -1;
}