how to solve error QXcbConnection: Could not connect to display when using exec function for phantomJs using PHP

php linux apache phantomjs ubuntu-16.04

13,823

Solution 1

Did you tried to set an environment variable on your server ? or added it before calling phantomjs ?

I was in the same situation and found some solutions:

a. define or set variable QT_QPA_PLATFORM to offscreen:

QT_QPA_PLATFORM=offscreen /usr/bin/phantomjs index.js

b. or add this line into your .bashrc file (put it at the end):

export QT_QPA_PLATFORM=offscreen

c. or install the package xvfb and call xvfb-run before phantomjs:

xvfb-run /usr/bin/phantomjs index.js

d. or use the parameter platform:

/usr/bin/phantomjs -platform offscreen index.js

Maybe you don't want / can't make modification on your server and in that case you may try to download the static binary from official website then:

/path/to/the/bin/folder/phantomjs index.js

and / or create an alias in your .bash_aliases file like this:

alias phantomjs=/path/to/the/bin/folder/phantomjs

make sure that phantomjs is not installed already on the system if you decide to use the alias.

if the file .bash_aliases not exist already, feel free to create it or add the alias line at the end of the .bashrc file

Some references:

Solution 2

I had the same problem running phantomjs on headless Ubuntu 18.04 (on the default Vagrant vm install of openstreetmap-website). Folloiwng Jiab77's links, it seems the Phantomjs team says the problem is the Debian package but the Debian team closed the bug as wontfix. I needed phantomjs to "just work" so it can be called by other programs that expect it to work normally. Specifically, openstreetmap-website has an extensive Ruby test suite with over 40 tests that were failing because of this, and I didn't want to modify all those tests.

Following Jiab77's answer, here's how I made it work:

As root, cp /usr/bin/phantomjs /usr/local/bin/phantomjs
Edit /usr/local/bin/phantomjs and add the line export QT_QPA_PLATFORM=offscreen so it runs before execution. Here is what mine says after doing so:

#!/bin/sh LD_LIBRARY_PATH="/usr/lib/phantomjs:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH # 2018-11-13: added the next line so phantomjs can run headless as explained on # https://stackoverflow.com/questions/49154209/how-to-solve-error-qxcbconnection-could-not-connect-to-display-when-using-exec export QT_QPA_PLATFORM=offscreen exec "/usr/lib/phantomjs/phantomjs" "$@"

After this change, phantomjs can be run from the command line without changing anything else, and all the tests that depend on phantomjs were successfully passed.

13,823

Author by

Shakti Sisodiya

Updated on June 14, 2022

Comments

Shakti Sisodiya almost 2 years

I am working on a project where I want to use PHP and Phantomjs together, I have completed my phantomJs script and trying to run it using php exec function. but the function is returning an array of error list. below I am writing my code of phantomjs and php

dir: /var/www/html/phantom/index.js

var page = require('webpage').create();
var fs = require('fs');

page.open('http://insttaorder.com/', function(status) {
    // Get all links to CSS and JS on the page
    var links = page.evaluate(function() {

        var urls = [];

        $("[rel=stylesheet]").each(function(i, css) {
            urls.push(css.href);
        });

        $("script").each(function(i, js) {
            if (js.src) {
                urls.push(js.src);
            }
        });

        return urls;
    });

    // Save all links to a file
    var url_file = "list.txt";
    fs.write(url_file, links.join("\n"), 'w');

    // Launch wget program to download all files from the list.txt to current
    // folder
    require("child_process").execFile("wget", [ "-i", url_file ], null,
            function(err, stdout, stderr) {

                console.log("execFileSTDOUT:", stdout);
                console.log("execFileSTDERR:", stderr);

                // After wget finished exit PhantomJS
                phantom.exit();

            });

});

dir: /var/www/html/phantom/index.php

exec('/usr/bin/phantomjs  index.js 2>&1',$output);
echo '<pre>';
print_r($output);
die;

Also tried with

 exec('/usr/bin/phantomjs  /var/www/html/phantom/index.js 2>&1',$output);
    echo '<pre>';
    print_r($output);
    die;

After runing this i am getting below error

Array
(
    [0] => QXcbConnection: Could not connect to display
    [1] => PhantomJS has crashed. Please read the bug reporting guide at
    [2] =>  and file a bug report.
    [3] => Aborted (core dumped)
)

But if I run index.php file from the terminal like this:

user2@user2-H81M-S:/var/www/html/phantom$ php index.php

then it works fine.I don't know how to solve it. Please help.

i am using following version

system version: Ubuntu 16.04.2 LTS
PHP version: 5.6
phantomJs version: 2.1.1

Jiab77 almost 6 years

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