mediawiki-extensions-Math/MathRestbaseInterface.php
Moritz Schubotz f5fdda0ba1 Improve error reporting
Display error message in the UI,
if the check command passes,
but the mml/svg/complete endpoints returns an valid json error.

Bug: T143225
Change-Id: I50776926e42f75a2c1e30fc9afe08baae3fcdbd1
2016-08-17 21:15:02 +02:00

452 lines
11 KiB
PHP

<?php
/**
* MediaWiki math extension
*
* (c) 2002-2015 various MediaWiki contributors
* GPLv2 license; info in main package.
*/
use MediaWiki\Logger\LoggerFactory;
class MathRestbaseInterface {
private $hash = false;
private $tex;
private $type;
private $checkedTex;
private $success;
private $identifiers;
private $error;
private $mathoidStyle;
private $mml;
/** @var boolean is there a request to purge the existing mathematical content */
private $purge = false;
/**
* MathRestbaseInterface constructor.
* @param string $tex
* @param string $type
*/
public function __construct( $tex = '', $type = 'tex' ) {
$this->tex = $tex;
$this->type = $type;
}
/**
* Bundles several requests for fetching MathML.
* Does not send requests, if the the input TeX is invalid.
* @param $rbis
* @param $serviceClient
*/
private static function batchGetMathML( $rbis, $serviceClient ) {
$requests = [];
$skips = [];
$i = 0;
foreach ( $rbis as $rbi ) {
/** @var MathRestbaseInterface $rbi */
if ( $rbi->getSuccess() ) {
$requests[] = $rbi->getContentRequest( 'mml' );
} else {
$skips[] = $i;
}
$i ++;
}
$results = $serviceClient->runMulti( $requests );
$lenRbis = count( $rbis );
$j = 0;
for ( $i = 0; $i < $lenRbis; $i ++ ) {
if ( !in_array( $i, $skips ) ) {
/** @var MathRestbaseInterface $rbi */
$rbi = $rbis[$i];
try {
$mml = $rbi->evaluateContentResponse( 'mml', $results[$j], $requests[$j] );
$rbi->mml = $mml;
}
catch ( Exception $e ) {
}
$j ++;
}
}
}
/**
* Lets this instance know if this is a purge request. When set to true,
* it will cause the object to issue the first content request with a
* 'Cache-Control: no-cache' header to prompt the regeneration of the
* renders.
*
* @param bool $purge whether this is a purge request
*/
public function setPurge( $purge = true ) {
$this->purge = $purge;
}
/**
* @return string MathML code
* @throws MWException
*/
public function getMathML() {
if ( !$this->mml ){
$this->mml = $this->getContent( 'mml' );
}
return $this->mml;
}
private function getContent( $type ) {
$request = $this->getContentRequest( $type );
$serviceClient = $this->getServiceClient();
$response = $serviceClient->run( $request );
return $this->evaluateContentResponse( $type, $response, $request );
}
private function calculateHash() {
if ( !$this->hash ) {
if ( !$this->checkTeX() ) {
throw new MWException( "TeX input is invalid." );
}
}
}
public function checkTeX() {
$request = $this->getCheckRequest();
$requestResult = $this->executeRestbaseCheckRequest( $request );
return $this->evaluateRestbaseCheckResponse( $requestResult );
}
/**
* Performs a service request
* Generates error messages on failure
* @see Http::post()
*
* @param array $request the request object
* @return bool success
*/
private function executeRestbaseCheckRequest( $request ) {
$res = null;
$serviceClient = $this->getServiceClient();
$response = $serviceClient->run( $request );
if ( $response['code'] !== 200 ) {
$this->log()->info( 'Tex check failed:', [
'post' => $request['body'],
'error' => $response['error'],
'url' => $request['url']
] );
}
return $response;
}
/**
* @param array $rbis array of MathRestbaseInterface instances
*/
public static function batchEvaluate( $rbis ) {
if ( count( $rbis ) == 0 ) {
return;
}
$requests = [];
/** @var MathRestbaseInterface $first */
$first = $rbis[0];
$serviceClient = $first->getServiceClient();
foreach ( $rbis as $rbi ) {
/** @var MathRestbaseInterface $rbi */
$requests[] = $rbi->getCheckRequest();
}
$results = $serviceClient->runMulti( $requests );
$i = 0;
foreach ( $results as $response ) {
/** @var MathRestbaseInterface $rbi */
$rbi = $rbis[$i ++];
try {
$rbi->evaluateRestbaseCheckResponse( $response );
} catch ( Exception $e ) {
}
}
self::batchGetMathML( $rbis, $serviceClient );
}
private function getServiceClient() {
global $wgVirtualRestConfig, $wgMathConcurrentReqs;
$http = new MultiHttpClient( [ 'maxConnsPerHost' => $wgMathConcurrentReqs ] );
$serviceClient = new VirtualRESTServiceClient( $http );
if ( isset( $wgVirtualRestConfig['modules']['restbase'] ) ) {
$cfg = $wgVirtualRestConfig['modules']['restbase'];
$cfg['parsoidCompat'] = false;
$vrsObject = new RestbaseVirtualRESTService( $cfg );
$serviceClient->mount( '/mathoid/', $vrsObject );
}
return $serviceClient;
}
/**
* The URL is generated accoding to the following logic:
*
* Case A: <code>$internal = false</code>, which means one needs an URL that is accessible from
* outside:
*
* --> If <code>$wgMathFullRestbaseURL</code> is configured use it, otherwise fall back try to
* <code>$wgVisualEditorFullRestbaseURL</code>. (Note, that this is not be worse than failing
* immediately.)
*
* Case B: <code> $internal= true</code>, which means one needs to access content from Restbase
* which does not need to be accessible from outside:
*
* --> Use the mount point whenever possible. If the mount point is not available, use
* <code>$wgMathFullRestbaseURL</code> with fallback to <code>wgVisualEditorFullRestbaseURL</code>
*
* @param string $path
* @param bool|true $internal
* @return string
* @throws MWException
*/
public function getUrl( $path, $internal = true ) {
global $wgVirtualRestConfig, $wgMathFullRestbaseURL, $wgVisualEditorFullRestbaseURL;
if ( $internal && isset( $wgVirtualRestConfig['modules']['restbase'] ) ) {
return "/mathoid/local/v1/$path";
}
if ( $wgMathFullRestbaseURL ) {
return "{$wgMathFullRestbaseURL}v1/$path";
}
if ( $wgVisualEditorFullRestbaseURL ) {
return "{$wgVisualEditorFullRestbaseURL}v1/$path";
}
$msg = 'Math extension can not find Restbase URL. Please specify $wgMathFullRestbaseURL.';
$this->setErrorMessage( $msg );
throw new MWException( $msg );
}
/**
* @return \Psr\Log\LoggerInterface
*/
private function log() {
return LoggerFactory::getInstance( 'Math' );
}
public function getSvg() {
return $this->getContent( 'svg' );
}
/**
* @param bool|false $skipConfigCheck
* @return bool
*/
public function checkBackend( $skipConfigCheck = false ) {
try {
$request = [
'method' => 'GET',
'url' => $this->getUrl( '?spec' )
];
} catch ( Exception $e ) {
return false;
}
$serviceClient = $this->getServiceClient();
$response = $serviceClient->run( $request );
if ( $response['code'] === 200 ) {
return $skipConfigCheck || $this->checkConfig();
}
$this->log()->error( "Restbase backend is not correctly set up.", [
'request' => $request,
'response' => $response
] );
return false;
}
/**
* Generates a unique TeX string, renders it and gets it via a public URL.
* The method fails, if the public URL does not point to the same server, who did render
* the unique TeX input in the first place.
* @return bool
*/
private function checkConfig() {
// Generates a TeX string that probably has not been generated before
$uniqueTeX = uniqid( 't=', true );
$testInterface = new MathRestbaseInterface( $uniqueTeX );
if ( ! $testInterface->checkTeX() ){
$this->log()->warning( 'Config check failed, since test expression was considered as invalid.',
[ 'uniqueTeX' => $uniqueTeX ] );
return false;
}
try {
$url = $testInterface->getFullSvgUrl();
$req = MWHttpRequest::factory( $url );
$status = $req->execute();
if ( $status->isOK() ){
return true;
}
$this->log()->warning( 'Config check failed, due to an invalid response code.',
[ 'responseCode' => $status ] );
} catch ( Exception $e ) {
$this->log()->warning( 'Config check failed, due to an exception.', [ $e ] );
return false;
}
}
/**
* Gets a publicly accessible link to the generated SVG image.
* @return string
* @throws MWException
*/
public function getFullSvgUrl() {
$this->calculateHash();
return $this->getUrl( "media/math/render/svg/{$this->hash}", false );
}
/**
* @return string
*/
public function getCheckedTex() {
return $this->checkedTex;
}
/**
* @return boolean
*/
public function getSuccess() {
if ( $this->success === null ) {
$this->checkTeX();
}
return $this->success;
}
/**
* @return array
*/
public function getIdentifiers() {
return $this->identifiers;
}
/**
* @return stdClass
*/
public function getError() {
return $this->error;
}
/**
* @return string
*/
public function getTex() {
return $this->tex;
}
/**
* @return string
*/
public function getType() {
return $this->type;
}
private function setErrorMessage( $msg ) {
$this->error = (object)[ 'error' => (object)[ 'message' => $msg ] ];
}
/**
* @return array
* @throws MWException
*/
public function getCheckRequest() {
$request = [
'method' => 'POST',
'body' => [
'type' => $this->type,
'q' => $this->tex
],
'url' => $this->getUrl( "media/math/check/{$this->type}" )
];
return $request;
}
/**
* @param $response
* @return bool
*/
public function evaluateRestbaseCheckResponse( $response ) {
$json = json_decode( $response['body'] );
if ( $response['code'] === 200 ) {
$headers = $response['headers'];
$this->hash = $headers['x-resource-location'];
$this->success = $json->success;
$this->checkedTex = $json->checked;
$this->identifiers = $json->identifiers;
return true;
} else {
if ( isset( $json->detail ) && isset( $json->detail->success ) ) {
$this->success = $json->detail->success;
$this->error = $json->detail;
} else {
$this->success = false;
$this->setErrorMessage( 'Math extension cannot connect to Restbase.' );
}
return false;
}
}
/**
* @return mixed
*/
public function getMathoidStyle() {
return $this->mathoidStyle;
}
/**
* @param $type
* @return array
* @throws MWException
*/
private function getContentRequest( $type ) {
$this->calculateHash();
$request = [
'method' => 'GET',
'url' => $this->getUrl( "media/math/render/$type/{$this->hash}" )
];
if ( $this->purge ) {
$request['headers'] = [
'Cache-Control' => 'no-cache'
];
$this->purge = false;
}
return $request;
}
/**
* @param $type
* @param $response
* @param $request
* @return mixed
* @throws MWException
*/
private function evaluateContentResponse( $type, $response, $request ) {
if ( $response['code'] === 200 ) {
if ( array_key_exists( 'x-mathoid-style', $response['headers'] ) ) {
$this->mathoidStyle = $response['headers']['x-mathoid-style'];
}
return $response['body'];
}
// Remove "convenience" duplicate keys put in place by MultiHttpClient
unset( $response[0], $response[1], $response[2], $response[3], $response[4] );
$this->log()->error( 'Restbase math server problem:', [
'request' => $request,
'response' => $response,
'math_type' => $type,
'tex' => $this->tex
] );
self::throwContentError( $type, $response['body'] );
}
/**
* @param $type
* @param $body
* @throws MWException
*/
public static function throwContentError( $type, $body ) {
$detail = 'Server problem.';
$json = json_decode( $body );
if ( isset( $json->detail ) ) {
if ( is_array( $json->detail ) ){
$detail = $json->detail[0];
} elseif ( is_string( $json->detail ) ) {
$detail = $json->detail;
}
}
throw new MWException( "Cannot get $type. $detail" );
}
}