Cron job permission issue?

Question

crontab.xml:

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Cron:etc/crontab.xsd">
    <group id="default">
        <job name="test_product_import" instance="Test\ImportExport\Cron\ProductImport" method="execute">
            <schedule>* * * * *</schedule>
        </job>
    </group>
</config>

Php File that gets called by cron:

<?php

namespace Test\ImportExport\Cron;

class ProductImport
{
    protected $trace;

    public function __construct(
        \Test\Core\Model\Trace $trace
    )
    {
        $this->trace = $trace;
    }

    public function execute()
    {
        $this->trace->writeTrace("Test");
    }
}

Error message in cron_schedule table :

Warning: fopen(app/code/Test/Trace.txt): failed to open stream: No such file or directory in /var/www/www.example.com/app/code/Test/Core/Model/Trace.php on line 12

On line 12 in this file:

$tracelog = fopen("app/code/Test/Trace.txt", "a") or die("Unable to open file!");

In SSH I executed

php magento cron:run

and I got the error. Since I assume a permission problem I tried

sudo -u www-data php magento cron:run

same issue. What's wrong?

Answer 1

I was able to solve it.

$tracelog = fopen("app/code/Test/Trace.txt", "a") or die("Unable to open file!");

I had to specify the absolute path to the file instead of the relative as shown above.