includes/Request/PathRouter.php
<?php
/**
* Parser to extract query parameters out of REQUEST_URI paths.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
namespace MediaWiki\Request;
use FatalError;
use stdClass;
/**
* MediaWiki\Request\PathRouter class.
* This class can take patterns such as /wiki/$1 and use them to
* parse query parameters out of REQUEST_URI paths.
*
* $router->add( "/wiki/$1" );
* - Matches /wiki/Foo style urls and extracts the title
* $router->add( [ 'edit' => "/edit/$key" ], [ 'action' => '$key' ] );
* - Matches /edit/Foo style urls and sets action=edit
* $router->add( '/$2/$1',
* [ 'variant' => '$2' ],
* [ '$2' => [ 'zh-hant', 'zh-hans' ] ]
* );
* - Matches /zh-hant/Foo or /zh-hans/Foo
* $router->addStrict( "/foo/Bar", [ 'title' => 'Baz' ] );
* - Matches /foo/Bar explicitly and uses "Baz" as the title
* $router->add( '/help/$1', [ 'title' => 'Help:$1' ] );
* - Matches /help/Foo with "Help:Foo" as the title
* $router->add( '/$1', [ 'foo' => [ 'value' => 'bar$2' ] ] );
* - Matches /Foo and sets 'foo' to 'bar$2' without $2 being replaced
* $router->add( '/$1', [ 'data:foo' => 'bar' ], [ 'callback' => 'functionname' ] );
* - Matches /Foo, adds the key 'foo' with the value 'bar' to the data array
* and calls functionname( &$matches, $data );
*
* Path patterns:
* - Paths may contain $# patterns such as $1, $2, etc...
* - $1 will match 0 or more while the rest will match 1 or more
* - Unless you use addStrict "/wiki" and "/wiki/" will be expanded to "/wiki/$1"
*
* Params:
* - In a pattern $1, $2, etc... will be replaced with the relevant contents
* - If you used a keyed array as a path pattern, $key will be replaced with
* the relevant contents
* - The default behavior is equivalent to `[ 'title' => '$1' ]`,
* if you don't want the title parameter you can explicitly use `[ 'title' => false ]`
* - You can specify a value that won't have replacements in it
* using `'foo' => [ 'value' => 'bar' ];`
*
* Options:
* - The option keys $1, $2, etc... can be specified to restrict the possible values
* of that variable. A string can be used for a single value, or an array for multiple.
* - When the option key 'strict' is set (Using addStrict is simpler than doing this directly)
* the path won't have $1 implicitly added to it.
* - The option key 'callback' can specify a callback that will be run when a path is matched.
* The callback will have the arguments ( &$matches, $data ) and the matches array can
* be modified.
*
* @since 1.19
* @author Daniel Friesen
*/
class PathRouter {
/**
* @var stdClass[]
*/
private $patterns = [];
/**
* Protected helper to do the actual bulk work of adding a single pattern.
* This is in a separate method so that add() can handle the difference between
* a single string $path and an array $path that contains multiple path
* patterns each with an associated $key to pass on.
* @param string $path
* @param array $params
* @param array $options
* @param null|string $key
*/
protected function doAdd( $path, $params, $options, $key = null ) {
// Make sure all paths start with a /
if ( $path[0] !== '/' ) {
$path = '/' . $path;
}
if ( !isset( $options['strict'] ) || !$options['strict'] ) {
// Unless this is a strict path make sure that the path has a $1
if ( strpos( $path, '$1' ) === false ) {
if ( $path[-1] !== '/' ) {
$path .= '/';
}
$path .= '$1';
}
}
// If 'title' is not specified and our path pattern contains a $1
// Add a default 'title' => '$1' rule to the parameters.
if ( !isset( $params['title'] ) && strpos( $path, '$1' ) !== false ) {
$params['title'] = '$1';
}
// If the user explicitly marked 'title' as false then omit it from the matches
if ( isset( $params['title'] ) && $params['title'] === false ) {
unset( $params['title'] );
}
// Loop over our parameters and convert basic key => string
// patterns into fully descriptive array form
foreach ( $params as $paramName => $paramData ) {
if ( is_string( $paramData ) ) {
if ( preg_match( '/\$(\d+|key)/u', $paramData ) ) {
$paramArrKey = 'pattern';
} else {
// If there's no replacement use a value instead
// of a pattern for a little more efficiency
$paramArrKey = 'value';
}
$params[$paramName] = [
$paramArrKey => $paramData
];
}
}
// Loop over our options and convert any single value $# restrictions
// into an array so we only have to do in_array tests.
foreach ( $options as $optionName => $optionData ) {
if ( preg_match( '/^\$\d+$/u', $optionName ) && !is_array( $optionData ) ) {
$options[$optionName] = [ $optionData ];
}
}
$pattern = (object)[
'path' => $path,
'params' => $params,
'options' => $options,
'key' => $key,
];
$pattern->weight = self::makeWeight( $pattern );
$this->patterns[] = $pattern;
}
/**
* Add a new path pattern to the path router
*
* @param string|array $path The path pattern to add
* @param array $params The params for this path pattern
* @param array $options The options for this path pattern
*/
public function add( $path, $params = [], $options = [] ) {
if ( is_array( $path ) ) {
foreach ( $path as $key => $onePath ) {
$this->doAdd( $onePath, $params, $options, $key );
}
} else {
$this->doAdd( $path, $params, $options );
}
}
/**
* @param string $path To be given to add()
* @param string $varName Full name of configuration variable for use
* in error message and url to mediawiki.org Manual (e.g. "wgExample").
* @throws FatalError If path is invalid
* @internal For use by WebRequest::getPathInfo
*/
public function validateRoute( $path, $varName ) {
if ( $path && !preg_match( '/^(https?:\/\/|\/)/', $path ) ) {
// T48998: Bail out early if path is non-absolute
throw new FatalError(
"If you use a relative URL for \$$varName, it must start " .
'with a slash (<code>/</code>).<br><br>See ' .
"<a href=\"https://www.mediawiki.org/wiki/Manual:\$$varName\">" .
"https://www.mediawiki.org/wiki/Manual:\$$varName</a>."
);
}
}
/**
* Add a new path pattern to the path router with the strict option on
* @param string|array $path
* @param array $params
* @param array $options
* @see self::add
*/
public function addStrict( $path, $params = [], $options = [] ) {
$options['strict'] = true;
$this->add( $path, $params, $options );
}
/**
* Protected helper to re-sort our patterns so that the most specific
* (most heavily weighted) patterns are at the start of the array.
*/
protected function sortByWeight() {
$weights = [];
foreach ( $this->patterns as $key => $pattern ) {
$weights[$key] = $pattern->weight;
}
array_multisort( $weights, SORT_DESC, SORT_NUMERIC, $this->patterns );
}
/**
* @param stdClass $pattern
* @return float|int
*/
protected static function makeWeight( $pattern ) {
# Start with a weight of 0
$weight = 0;
// Explode the path to work with
$path = explode( '/', $pattern->path );
# For each level of the path
foreach ( $path as $piece ) {
if ( preg_match( '/^\$(\d+|key)$/u', $piece ) ) {
# For a piece that is only a $1 variable add 1 points of weight
$weight += 1;
} elseif ( preg_match( '/\$(\d+|key)/u', $piece ) ) {
# For a piece that simply contains a $1 variable add 2 points of weight
$weight += 2;
} else {
# For a solid piece add a full 3 points of weight
$weight += 3;
}
}
foreach ( $pattern->options as $key => $option ) {
if ( preg_match( '/^\$\d+$/u', $key ) ) {
# Add 0.5 for restrictions to values
# This way given two separate "/$2/$1" patterns the
# one with a limited set of $2 values will dominate
# the one that'll match more loosely
$weight += 0.5;
}
}
return $weight;
}
/**
* Parse a path and return the query matches for the path
*
* @param string $path The path to parse
* @return array The array of matches for the path
*/
public function parse( $path ) {
// Make sure our patterns are sorted by weight so the most specific
// matches are tested first
$this->sortByWeight();
$matches = $this->internalParse( $path );
if ( $matches === null ) {
// Try with the normalized path (T100782)
$path = wfRemoveDotSegments( $path );
$path = preg_replace( '#/+#', '/', $path );
$matches = $this->internalParse( $path );
}
// We know the difference between null (no matches) and
// [] (a match with no data) but our WebRequest caller
// expects [] even when we have no matches so return
// a [] when we have null
return $matches ?? [];
}
/**
* Match a path against each defined pattern
*
* @param string $path
* @return array|null
*/
protected function internalParse( $path ) {
$matches = null;
foreach ( $this->patterns as $pattern ) {
$matches = self::extractTitle( $path, $pattern );
if ( $matches !== null ) {
break;
}
}
return $matches;
}
/**
* @param string $path
* @param stdClass $pattern
* @return array|null
*/
protected static function extractTitle( $path, $pattern ) {
// Convert the path pattern into a regexp we can match with
$regexp = preg_quote( $pattern->path, '#' );
// .* for the $1
$regexp = preg_replace( '#\\\\\$1#u', '(?P<par1>.*)', $regexp );
// .+ for the rest of the parameter numbers
$regexp = preg_replace( '#\\\\\$(\d+)#u', '(?P<par$1>.+?)', $regexp );
$regexp = "#^{$regexp}$#";
$matches = [];
$data = [];
// Try to match the path we were asked to parse with our regexp
if ( preg_match( $regexp, $path, $m ) ) {
// Ensure that any $# restriction we have set in our {$option}s
// matches properly here.
foreach ( $pattern->options as $key => $option ) {
if ( preg_match( '/^\$\d+$/u', $key ) ) {
$n = intval( substr( $key, 1 ) );
$value = rawurldecode( $m["par{$n}"] );
if ( !in_array( $value, $option ) ) {
// If any restriction does not match return null
// to signify that this rule did not match.
return null;
}
}
}
// Give our $data array a copy of every $# that was matched
foreach ( $m as $matchKey => $matchValue ) {
if ( preg_match( '/^par\d+$/u', $matchKey ) ) {
$n = intval( substr( $matchKey, 3 ) );
$data['$' . $n] = rawurldecode( $matchValue );
}
}
// If present give our $data array a $key as well
if ( isset( $pattern->key ) ) {
$data['$key'] = $pattern->key;
}
// Go through our parameters for this match and add data to our matches and data arrays
foreach ( $pattern->params as $paramName => $paramData ) {
$value = null;
// Differentiate data: from normal parameters and keep the correct
// array key around (ie: foo for data:foo)
if ( preg_match( '/^data:/u', $paramName ) ) {
$isData = true;
$key = substr( $paramName, 5 );
} else {
$isData = false;
$key = $paramName;
}
if ( isset( $paramData['value'] ) ) {
// For basic values just set the raw data as the value
$value = $paramData['value'];
} elseif ( isset( $paramData['pattern'] ) ) {
// For patterns we have to make value replacements on the string
$value = self::expandParamValue( $m, $pattern->key ?? null,
$paramData['pattern'] );
if ( $value === false ) {
// Pattern required data that wasn't available, abort
return null;
}
}
// Send things that start with data: to $data, the rest to $matches
if ( $isData ) {
$data[$key] = $value;
} else {
$matches[$key] = $value;
}
}
// If this match includes a callback, execute it
if ( isset( $pattern->options['callback'] ) ) {
call_user_func_array( $pattern->options['callback'], [ &$matches, $data ] );
}
} else {
// Our regexp didn't match, return null to signify no match.
return null;
}
// Fall through, everything went ok, return our matches array
return $matches;
}
/**
* Replace $key etc. in param values with the matched strings from the path.
*
* @param array $pathMatches The match results from the path
* @param string|null $key The key of the matching pattern
* @param string $value The param value to be expanded
* @return string|false
*/
protected static function expandParamValue( $pathMatches, $key, $value ) {
$error = false;
$replacer = static function ( $m ) use ( $pathMatches, $key, &$error ) {
if ( $m[1] == "key" ) {
if ( $key === null ) {
$error = true;
return '';
}
return $key;
} else {
$d = $m[1];
if ( !isset( $pathMatches["par$d"] ) ) {
$error = true;
return '';
}
return rawurldecode( $pathMatches["par$d"] );
}
};
$value = preg_replace_callback( '/\$(\d+|key)/u', $replacer, $value );
if ( $error ) {
return false;
}
return $value;
}
/**
* @param array $actionPaths
* @param string $articlePath
* @return string[]|false
* @internal For use by Title and WebRequest only.
*/
public static function getActionPaths( array $actionPaths, $articlePath ) {
if ( !$actionPaths ) {
return false;
}
// Processing of urls for this feature requires that 'view' is set.
// By default, set it to the pretty article path.
if ( !isset( $actionPaths['view'] ) ) {
$actionPaths['view'] = $articlePath;
}
return $actionPaths;
}
}
/** @deprecated class alias since 1.40 */
class_alias( PathRouter::class, 'PathRouter' );