JIRA REST API: oAuth Invalid Signature Issue

JIRA API oAuth fails with an invalid signature error. Below is a revised example:

<?php
class ApiConnector {
    public function execute() {
        $settings = [
            'url'      => getenv('JIRA_ENDPOINT'),
            'privKey'  => getenv('JIRA_PRIVKEY'),
            'appKey'   => getenv('JIRA_APPKEY'),
            'appSecret'=> getenv('JIRA_APPSECRET')
        ];
        // Perform authentication here
    }
}

hey im not sure but maybe check your key ording, extra spaces or a slight time diff can ruin the base string sig. give it a try!