Question

Is it possible to restream an internet radio using PHP?

Radio is available at port 8000. I would like to use my webserver and “transmit” the radio stream to port 80.

Is it possible?

I have already been googling it around and I found http://support.spacialnet.com/forums/viewtopic.php?f=13&t=16858&start=15 but it doesn’t work for me. It does actually work. Before I just forget to change MIME type of the stream.

I customized solution from previously mentioned URL (http://support.spacialnet.com/forums/viewtopic.php?f=13&t=16858&start=15). It does work now, but the stream always breaks after in about 8 minutes of listening. Any clue why?
(server max. execution time is set to 30 seconds). I tested different streams with various bitrates, but it behaves exactly same every time. Any help?

Answer 1

I probably shouldn’t be answering this question, but I had some free time at work and wanted to play with sockets a bit.

Here is my class, it isn’t well-tested(well, it worked on the first run which is suspicious) and may be buggy, but it may give you some usefull ideas. It strips ICY* headers as that example you posted, but that can be easily changed.

I tested it on Ubuntu Totem player and it played well for 10 minutes before I stopped it, but maybe I just got lucky (: At least 8 minutes seems not to be some magical number.

<?php

ob_start();

class RadioProxy {
    CONST STREAM_content_type='audio/aac';
    CONST STREAM_timeout=1.5;

    CONST HTTP_response_header_first='/\s200\s/';
    CONST HTTP_response_header_pattern='/^[a-z\-]+:/i';
    CONST HTTP_max_line_length=1024;

    CONST HTTP_delim="\r\n";
    CONST HTTP_max_response_headers=40;
    CONST ERROR_max=5;
    CONST ERROR_interval=120;
    CONST ERROR_usleep=300000;


    private $server_name, $server_port;
    private $HTTP_headers;
    private $STREAM = NULL;
    private $STREAM_errors = array();
    private $TIMEOUT_seconds, $TIMEOUT_microseconds;

    public function __construct($server_name, $server_port, $filename='') {
        self::STREAM_set_headers();
        $this->server_name = $server_name;
        $this->server_port = $server_port;
        $this->HTTP_headers = $this->HTTP_generate_headers($filename);
        $this->connect();
    }

    private function connect() {
        $HTTP_headers_length = strlen($this->HTTP_headers);
        do {

            if (!$this->STREAM_connect()) {
                continue;
            }

            if (!$this->STREAM_send_headers()) {
                continue;
            }

            if (!$this->STREAM_skip_headers()) {
                continue;
            }

            if (!$this->STREAM_proxy()) {
                continue;
            }
        } while ($this->ERROR_is_accepteble());
    }

    private function HTTP_generate_headers($filename) {
        $header = '';
        self::HTTP_add_header($header, 'GET /' . rawurlencode($filename) . ' HTTP/1.0');
        self::HTTP_add_header($header, 'Host: ' . $this->server_name);
        self::HTTP_add_header($header, 'User-Agent: WinampMPEG/5.11');
        self::HTTP_add_header($header, 'Accept: */*');
        self::HTTP_add_header($header, 'Connection: close');
        //End of headers
        self::HTTP_add_header($header);
        return $header;
    }

    private static function HTTP_add_header(&$header, $new_header_line='') {
        $header.=$new_header_line . self::HTTP_delim;
    }

    private function ERROR_is_accepteble() {
        //Delete old errors
        array_filter($this->STREAM_errors, 'self::ERROR_remove_old');
        $this->STREAM_errors[] = time();
        usleep(self::ERROR_usleep);
        return count($this->STREAM_errors) <= self::ERROR_max;
    }

    private static function ERROR_remove_old($error_time) {
        return ($error_time - time()) <= self::ERROR_interval;
    }

    private function STREAM_connect() {
        if (!ob_get_level()) {
            ob_start();
        }
        ob_clean();
        if ($this->STREAM !== NULL) {
            fclose($this->STREAM);
        }
        $this->STREAM = fsockopen($this->server_name, $this->server_port);

        if ($this->STREAM === FALSE) {
            return FALSE;
        }

        $this->TIMEOUT_seconds = floor(self::STREAM_timeout);
        $this->TIMEOUT_microseconds = ceil((self::STREAM_timeout - $this->TIMEOUT_seconds) * 1000);
        return stream_set_timeout($this->STREAM, $this->TIMEOUT_seconds, $this->TIMEOUT_microseconds);
    }

    private function STREAM_send_headers() {
        return fwrite($this->STREAM, $this->HTTP_headers) === strlen($this->HTTP_headers);
    }

    private function STREAM_skip_headers() {
        $read_expect = array($this->STREAM);

        $if_first_header = true;
        $header_lines_count = 0;

        do {
            stream_select($read_expect, $NULL, $NULL, $this->TIMEOUT_seconds, $this->TIMEOUT_microseconds);

            $header_line = stream_get_line($this->STREAM, self::HTTP_max_line_length, self::HTTP_delim);

            if ($header_line === FALSE) {
                return FALSE;
            }
            if ($if_first_header) {
                $if_first_header = false;

                if (!preg_match(self::HTTP_response_header_first, $header_line)) {
                    return FALSE;
                }
                continue;
            }

            if (empty($header_line)) {
                return TRUE;
            }

            if (!preg_match(self::HTTP_response_header_pattern, $header_line)) {
                return FALSE;
            }

            $header_lines_count++;
        } while ($header_lines_count < self::HTTP_max_response_headers);

        return FALSE;
    }

    private function STREAM_proxy() {
        $read_expect = array($this->STREAM);

        //No output buffering should be here!
        while (@ob_end_clean ());

        do {
            stream_select($read_expect, $NULL, $NULL, $this->TIMEOUT_seconds, $this->TIMEOUT_microseconds);
        } while (fpassthru($this->STREAM));
    }

    private static function STREAM_set_headers() {
        //Clean all output
        ob_clean();
        header("Content-type: " . self::STREAM_content_type);
        ob_flush();
    }

}

$TestRadio = new RadioProxy('XXX.XXX.XXX.XXX', XXXX,'XXXX.mp3');

P.S. Don’t do this.