Scalr_Environment::applyGlobalVarsToValue PHP Method

    public function applyGlobalVarsToValue($value)
    {
        if (empty($this->globalVariablesCache)) {
            $formats = \Scalr::config("scalr.system.global_variables.format");
            $systemVars = array('env_id' => $this->id, 'env_name' => $this->name);
            // Get list of Server system vars
            foreach ($systemVars as $name => $val) {
                $name = "SCALR_" . strtoupper($name);
                $val = trim($val);
                if (isset($formats[$name])) {
                    $val = @sprintf($formats[$name], $val);
                }
                $this->globalVariablesCache[$name] = $val;
            }
            // Add custom variables
            $gv = new Scalr_Scripting_GlobalVariables($this->clientId, $this->id, ScopeInterface::SCOPE_ENVIRONMENT);
            $vars = $gv->listVariables();
            foreach ($vars as $v) {
                $this->globalVariablesCache[$v['name']] = $v['value'];
            }
        }
        //Parse variable
        $keys = array_keys($this->globalVariablesCache);
        $keys = array_map(function ($item) {
            return '{' . $item . '}';
        }, $keys);
        $values = array_values($this->globalVariablesCache);
        $retval = str_replace($keys, $values, $value);
        // Strip undefined variables & return value
        return preg_replace("/{[A-Za-z0-9_-]+}/", "", $retval);
    }