PHP7 Check for missing modules incomplete (should check for php-xml)

[flurischt]

How to use GitHub

• Please use the 👍 reaction to show that you are affected by the same issue.
• Please don't comment if you have no relevant information to add. It's just extra noise for everyone subscribed to this issue.
• Subscribe to receive notifications on status change and new comments.

Steps to reproduce

Nextcloud seems to check if a required php module is missing. This does not seem to be the case for php-xml. If this module is missing only a 500 server error is reported when accessing the page.

1. Install nextcloud on a machine using php7.0 and WITHOUT the php7.0-xml module installed
2. Access the nextcloud login page

Expected behaviour

Nextcloud should tell me that the xml php module is missing as it does for other modules (like mbstring for example).

Actual behaviour

A 500 server error is thrown and then I need to check the log. The log tells me:

Exception: {\"Exception\":\"Error\",\"Message\":\"Call to undefined function OC\\\\AppFramework\\\\simplexml_load_file()\",\"Code\":0,\"Trace\":\"#0 \\\/var\\\/www\\\/nextcloud\\\/lib\\\/private\\\/legacy\\\/app.php(177): OC\\\\AppFramework\\\\App::buildAppNamespace('files')\\n#1 \\\/var\\\/www\\\/nextcloud\\\/lib\\\/private\\\/legacy\\\/app.php(115): OC_App::registerAutoloading('files', '\\\/var\\\/www\\\/nextcl...')\\n#2 \\\/var\\\/www\\\/nextcloud\\\/lib\\\/base.php(658): OC_App::loadApps(Array)\\n#3 \\\/var\\\/www\\\/nextcloud\\\/lib\\\/base.php(1059): OC::init()\\n#4 \\\/var\\\/www\\\/nextcloud\\\/index.php(46): require_once('\\\/var\\\/www\\\/nextcl...')\\n#5 {main}\",\"File\":\"\\\/var\\\/www\\\/nextcloud\\\/lib\\\/private\\\/AppFramework\\\/App.php\",\"Line\":60}

And then I have to figure out myself that this may be due to a missing php module.

Server configuration

Operating system: Ubuntu Xenial

Web server: Apache 2x

Database: MariaDB

PHP version: 7.0

Nextcloud version: 10.0.1

Updated from an older Nextcloud/ownCloud or fresh install: Updated from owncloud -> nextcloud 9 -> nextcloud 10.0.1

[LukasReschke]

We actually check for this at

server/lib/private/legacy/util.php

Lines 731 to 765 in d7dd399

	// Contains the dependencies that should be checked against
	// classes = class_exists
	// functions = function_exists
	// defined = defined
	// ini = ini_get
	// If the dependency is not found the missing module name is shown to the EndUser
	// When adding new checks always verify that they pass on Travis as well
	// for ini settings, see https://github.com/owncloud/administration/blob/master/travis-ci/custom.ini
	$dependencies = array(
	'classes' => array(
	'ZipArchive' => 'zip',
	'DOMDocument' => 'dom',
	'XMLWriter' => 'XMLWriter',
	'XMLReader' => 'XMLReader',
	),
	'functions' => [
	'xml_parser_create' => 'libxml',
	'mb_strcut' => 'mb multibyte',
	'ctype_digit' => 'ctype',
	'json_encode' => 'JSON',
	'gd_info' => 'GD',
	'gzencode' => 'zlib',
	'iconv' => 'iconv',
	'simplexml_load_string' => 'SimpleXML',
	'hash' => 'HASH Message Digest Framework',
	'curl_init' => 'cURL',
	'openssl_verify' => 'OpenSSL',
	],
	'defined' => array(
	'PDO::ATTR_DRIVER_NAME' => 'PDO'
	),
	'ini' => [
	'default_charset' => 'UTF-8',
	],
	);

. I suspect this code path is not reached because the simplexml_load_file is executed before.

[adsworth]

Yes, it looks like simplexml_load_file is called at /lib/private/App/InfoParser.php#61

At least I get this in my logs:
{"reqId":"WEs3Ouaby31h2jIpj4c3fAAAAAA","remoteAddr":"127.0.0.1","app":"PHP","message":"Call to undefined function OC\App\simplexml_load_file() at /home/adi/public_html/nc/lib/private/App/InfoParser.php#61","level":3,"time":"2016-12-09T22:59:06+00:00","method":"GET","url":"/~adi/nc/index.php/apps/files/?dir=/&fileid=2","user":"--","version":"11.0.0.6"}

[adsworth]

here is the stack if that is of interest:

Array
(
    [0] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/private\/legacy\/app.php
            [line] => 706
            [function] => parse
            [class] => OC\\App\\InfoParser
            [object] => OC\\App\\InfoParser Object
                (
                    [cache:OC\\App\\InfoParser:private] => OC\\Memcache\nullCache Object
                        (
                            [prefix:protected] => 26e183a52d718a752f577b9fd14d4a8f\/core.appinfo
                        )
                )
            [type] => ->
            [args] => Array
                (
                    [0] => \/home\/adi\/public_html\/nc\/apps\/files\/appinfo\/info.xml
                )
        )
   [1] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/private\/AppFramework\/App.php
            [line] => 62
            [function] => getAppInfo
            [class] => OC_App
            [type] => ::
            [args] => Array
                (
                    [0] => files
                )
        )
    [2] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/private\/legacy\/app.php
            [line] => 196
            [function] => buildAppNamespace
            [class] => OC\\AppFramework\\App
            [type] => ::
            [args] => Array
                (
                    [0] => files
                )
        )
    [3] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/private\/legacy\/app.php
            [line] => 117
            [function] => registerAutoloading
            [class] => OC_App
            [type] => ::
            [args] => Array
                (
                    [0] => files
                    [1] => \/home\/adi\/public_html\/nc\/apps\/files
                )
        )
    [4] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/base.php
            [line] => 676
            [function] => loadApps
            [class] => OC_App
            [type] => ::
            [args] => Array
                (
                    [0] => Array
                        (
                            [0] => session
                        )
                )
        )
    [5] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/lib\/base.php
            [line] => 1092
            [function] => init
            [class] => OC
            [type] => ::
            [args] => Array
                (
                )
        )
    [6] => Array
        (
            [file] => \/home\/adi\/public_html\/nc\/index.php
            [line] => 38
            [args] => Array
                (
                    [0] => \/home\/adi\/public_html\/nc\/lib\/base.php
                )
            [function] => require_once
        )
)

[MorrisJobke]

@nickvergessen Thanks for taking over this one

[nickvergessen]

Fix at #2619