PHP Composer Can’t find autoloaded file

I am trying to autoload a file and my PSR-4 autoloading worked fine locally however now that I am deploying to a baremetal server. It is not working and PHP states that it can’t find the autoloaded file. This is the current error:

Fatal error: Class ‘MetabaseModelsCron’ not found in /usr/www/users/metabase/src/commands/ArticleFetchCron.php on line 25

My composer.json is as follows:

{
"require": {
    "vlucas/phpdotenv": "^2.4",
    "guzzlehttp/guzzle": "6.3",
    "monolog/monolog": "^1.23",
    "illuminate/http": "^5.7@dev"
},
"autoload": {
    "psr-4": {"Metabase\": "src/"}
}
}

The file that is having an issue is including the namespaces correctly as far as I know:

<?php

namespace MetabaseCommands;

// autoload composer
require_once(__DIR__ . '/../../vendor/autoload.php');

/**
 * Class ArticleFetchCron
 * @package MetabaseCommands
 */
use MetabaseApiRequestsArticleRequest;
use MetabaseModelsCron;
use MetabaseModelsCronInterface;
use MetabaseModelsDatabaseAdapter;

class ArticleFetchCron extends Cron
implements CronInterface

I am just wondering if I have perhaps made a mistake with my composer.json file?

Answer

The PSR-4 based class autoloader implemented by Composer, when asked to find MetabaseModelsCron, looks for a file called srcModelsCron.php. If your actual files are using a different case anywhere on the path such as srcmodelsCron.php you’ll get different results depending on whether the underlying file system is case sensitive or not. The reason is simple:

• If the file system is case sensitive it can physically contain two directories called srcmodels and srcModels and you’re loading the wrong one.

• If it isn’t, both paths are actually identical to all effects.

Double-check file names and rebuild the autoloader with composer dump-autoload.