CraftCli\Support\Downloader\BaseDownloader::download PHP Method

    public function download()
    {
        if (!ini_get('allow_url_fopen')) {
            throw new Exception('allow_url_fopen is disabled.');
        }
        // open the temp file for writing
        $fileHandle = fopen($this->path, 'wb');
        if ($fileHandle === false) {
            throw new Exception('Could not open temp file.');
        }
        $caPath = CaBundle::getSystemCaRootBundlePath();
        if (is_dir($caPath)) {
            $streamOptions = array('ssl' => array('capath' => $caPath));
        } else {
            $streamOptions = array('ssl' => array('cafile' => $caPath));
        }
        $streamParams = array('notification' => array($this, 'showDownloadProgress'));
        // download context so we can track download progress
        $downloadContext = stream_context_create($streamOptions, $streamParams);
        // open the download url for reading
        $downloadHandle = @fopen($this->url, 'rb', false, $downloadContext);
        if ($downloadHandle === false) {
            throw new Exception('Could not download installation file.');
        }
        while (!feof($downloadHandle)) {
            if (fwrite($fileHandle, fread($downloadHandle, 1024)) === false) {
                throw new Exception('Could not write installation file to disk.');
            }
        }
        fclose($downloadHandle);
        fclose($fileHandle);
        if ($this->progressBar) {
            $this->progressBar->finish();
            $this->output->writeln('');
        }
        return $this->path;
    }