gnu-social/lib/util/xmloutputter.php
2021-07-16 19:44:37 +01:00

279 lines
7.7 KiB
PHP

<?php
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// GNU social is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with GNU social. If not, see <http://www.gnu.org/licenses/>.
/**
* Low-level generator for XML
*
* @package GNUsocial
* @category Output
*
* @author Evan Prodromou <evan@status.net>
* @author Sarven Capadisli <csarven@status.net>
* @copyright 2008-2019 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
defined('GNUSOCIAL') || die();
/**
* Low-level generator for XML
*
* This is a thin wrapper around PHP's XMLWriter. The main
* advantage is the element() method, which simplifies outputting
* an element.
*
* @see Action
* @see HTMLOutputter
*
* @copyright 2008-2019 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
class xmloutputter
{
/**
* Wrapped XMLWriter object, which does most of the heavy lifting
* for output.
*/
public $xw;
/**
* Constructor
*
* Initializes the wrapped XMLWriter.
*
* @param null|string $output URL for outputting, if null it defaults to stdout ('php://output')
* @param null|bool $indent Whether to indent output, if null it defaults to true
*
* @throws ServerException
*/
public function __construct($output = null, $indent = null)
{
if (is_null($output)) {
$output = 'php://output';
}
$this->xw = new XMLWriter();
$this->xw->openURI($output);
if (is_null($indent)) {
$indent = common_config('site', 'indent');
}
$this->xw->setIndent($indent);
}
/**
* Start a new XML document
*
* @param string $doc document element
* @param string $public public identifier
* @param string $system system identifier
*
* @return void
*/
public function startXML(?string $doc = null, ?string $public = null, ?string $system = null): void
{
$this->xw->startDocument('1.0', 'UTF-8');
if (!is_null($doc)) {
$this->xw->writeDTD($doc, $public, $system);
}
}
/**
* finish an XML document
*
* It's probably a bad idea to continue to use this object
* after calling endXML().
*
* @return void
*/
public function endXML(): void
{
$this->xw->endDocument();
$this->xw->flush();
}
/**
* output an XML element
*
* Utility for outputting an XML element. A convenient wrapper
* for a bunch of longer XMLWriter calls. This is best for
* when an element doesn't have any sub-elements; if that's the
* case, use elementStart() and elementEnd() instead.
*
* The $content element will be escaped for XML. If you need
* raw output, use elementStart() and elementEnd() with a call
* to raw() in the middle.
*
* If $attrs is a string instead of an array, it will be treated
* as the class attribute of the element.
*
* @param string $tag Element type or tagname
* @param null|array|string $attrs Array of element attributes, as key-value pairs
* @param null|string $content string content of the element
*
* @return void
*/
public function element(string $tag, $attrs = null, ?string $content = null): void
{
$this->elementStart($tag, $attrs);
if (!is_null($content)) {
$this->xw->text($content);
}
$this->elementEnd($tag);
}
/**
* output a start tag for an element
*
* Mostly used for when an element has content that's
* not a simple string.
*
* If $attrs is a string instead of an array, it will be treated
* as the class attribute of the element.
*
* @param string $tag Element type or tagname
* @param null|array|string $attrs Attributes
*
* @return void
*/
public function elementStart(string $tag, $attrs = null): void
{
$this->xw->startElement($tag);
if (is_array($attrs)) {
foreach ($attrs as $name => $value) {
$this->xw->writeAttribute($name, $value);
}
} elseif (is_string($attrs)) {
$this->xw->writeAttribute('class', $attrs);
}
}
/**
* output an end tag for an element
*
* Used in conjunction with elementStart(). $tag param
* should match the elementStart() param.
*
* For HTML 4 compatibility, this method will force
* a full end element (</tag>) even if the element is
* empty, except for a handful of exception tagnames.
* This is a hack.
*
* @param string $tag Element type or tagname.
*
* @return void
*/
public function elementEnd(string $tag): void
{
static $empty_tag = ['base', 'meta', 'link', 'hr',
'br', 'param', 'img', 'area',
'input', 'col', 'source', ];
// XXX: check namespace
if (in_array($tag, $empty_tag)) {
$this->xw->endElement();
} else {
$this->xw->fullEndElement();
}
}
/**
* @param array $ns
* @param string $tag
* @param null|array|string $attrs
* @param null|string $content
*
* @return void
*/
public function elementNS(array $ns, string $tag, $attrs = null, ?string $content = null): void
{
$this->elementStartNS($ns, $tag, $attrs);
if (!is_null($content)) {
$this->xw->text($content);
}
$this->elementEnd($tag);
}
/**
* @param array $ns
* @param string $tag
* @param null|array|string $attrs
*
* @return void
*/
public function elementStartNS(array $ns, string $tag, $attrs = null): void
{
reset($ns); // array pointer to 0
$uri = key($ns);
$this->xw->startElementNS($ns[$uri], $tag, $uri);
if (is_array($attrs)) {
foreach ($attrs as $name => $value) {
$this->xw->writeAttribute($name, $value);
}
} elseif (is_string($attrs)) {
$this->xw->writeAttribute('class', $attrs);
}
}
/**
* output plain text
*
* Text will be escaped. If you need it not to be,
* use raw() instead.
*
* @param string $txt Text to output.
*
* @return void
*/
public function text(string $txt): void
{
$this->xw->text($txt);
}
/**
* output raw xml
*
* This will spit out its argument verbatim -- no escaping is
* done.
*
* @param string $xml XML to output.
*
* @return void
*/
public function raw(string $xml): void
{
$this->xw->writeRaw($xml);
}
/**
* output a comment
*
* @param string $txt text of the comment
*
* @return void
*/
public function comment(string $txt): void
{
$this->xw->writeComment($txt);
}
/**
* Flush output buffers
*
* @return void
*/
public function flush(): void
{
$this->xw->flush();
}
}