Webserver (froscon)

Build your own Webserver with PHP.

Transcript

1. Build your own
   web server
   with
   

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2. @igorwesome
   

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4. no js
   

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5. HTTP: The Protocol
   

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6. Verbs
   •GET
   •POST
   

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7. Verbs
   •GET
   •POST
   •PUT
   •DELETE
   

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8. Verbs
   •GET
   •POST
   •PUT
   •DELETE
   •HEAD
   •OPTIONS
   •TRACE
   •CONNECT
   

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9. • 1xx - Special protocol stuff
   • 2xx - All good
   • 3xx - Redirection
   • 4xx - You are stupid
   • 5xx - Oh crap! I’m a fucking moron.
   Status codes
   

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10. • RFC 2324: HTCPCP
    • 418 - I’m a Teapot
    Status codes
    

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11. Status codes
    • 7xx - Developer Error
    • 710 - PHP
    • 712 - NoSQL
    • 720 - Unpossible
    • 724 - This line should be unreachable
    • 745 - I don’t always test my code, but when I do I do it in
    production
    • 759 - Unexpexted T_PAAMAYIM_NEKUDOTAYIM
    

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12. Redirection
    • 301 - Moved Permanently
    • 302 - Found (misused)
    • 303 - See Other
    • 305 - Use Proxy
    • 307 - Temporary Redirect
    • Location header
    

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13. Content Negotiation
    Accept: text/html
    Can haz html?
    

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14. Content Negotiation
    Accept: text/html
    Can haz html?
    Content-Type: application/json
    Server says no
    kthxbai
    

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15. Caching
    • Cache-Control: public/private, max-age
    • ETag / If-Match
    • Last-Modified / If-Modified-Since
    • 403 - Not Modified
    

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16. Authentication
    

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17. Basic Auth
    • 401 - Unauthorized
    • 403 - Forbidden
    • WWW-Authenticate: Basic realm=”foo”
    • Authorization: base64(username:password)
    

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18. Digest Auth
    • WWW-Authenticate:
    • Digest realm=”foo”
    • qop=”auth”
    • nonce=”123”
    • opaque=”456”
    • Authorization:
    • ha1 = md5(
    username:realm:pass
    )
    • ha2 = md5(
    method:digestURI
    )
    • value =
    md5(ha1:nonce:ha2)
    

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19. Keep-Alive
    

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20. Streaming
    • Transfer-Encoding: chunked
    • dechex(strlen($chunk)) \r\n $chunk \r\n
    • 0 \r\n \r\n
    

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21. Privacy
    GET /index.html HTTP/1.1.
    Host: 127.0.0.1.
    Connection: keep-alive.
    User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X
    10_7_4) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/
    21.0.1180.82 Safari/537.1.
    Accept: text/html,application/xhtml+xml,application/
    xml;q=0.9,*/*;q=0.8.
    Referer: http://127.0.0.1/foo.html.
    Accept-Encoding: gzip,deflate,sdch.
    Accept-Language: en-US,en;q=0.8.
    Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3.
    .
    

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22. Trailers
    

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23. HTTP/1.1
    RFC 2616
    read it, you know you want to!
    

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24. The Socket API
    

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25. ________
    < socket >
    --------
    \ ^__^
    \ (oo)\_______
    (__)\ )\/\
    ||----w |
    || ||
    

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26. Salami Pizza
    +---+--------------+----------------+
    | 7 | Application | HTTP, FTP, DNS |
    | 6 | Presentation | TLS |
    | 5 | Session | TCP |
    | 4 | Transport | TCP, UDP |
    | 3 | Network | IP |
    | 2 | Data Link | MAC, PPP |
    | 1 | Physical | |
    +---+--------------+----------------+
    

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27. #include
    #include
    #include
    socket()
    bind()
    listen()
    accept()
    

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28. Binding to ports
    Binding to IPs
    

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29. PHP Socket API
    $address = '0.0.0.0';
    $port = 5000;
    $sock = socket_create(AF_INET, SOCK_STREAM, 0);
    socket_bind($sock, $address, $port);
    socket_listen($sock);
    while (true) {
    $conn = socket_accept($sock);
    socket_write($conn, date(DATE_RFC822)."\n");
    socket_close($conn);
    }
    

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30. Stream Sockets
    

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31. $sock = stream_socket_server('tcp://0.0.0.0:5000');
    while (true) {
    $conn = stream_socket_accept($sock, -1);
    fwrite($conn, date(DATE_RFC822)."\n");
    fclose($conn);
    }
    

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32. $contents = file_get_contents('https://igor.io');
    

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33. $context = stream_context_create([
    'http' => [
    'method' => 'POST',
    'header' => "Accept: application/json\r\n",
    'content' => '{"secret":"data"}',
    ]
    ]);
    $contents = file_get_contents('https://igor.io', false, $context);
    var_dump($http_response_header);
    

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34. $sock = stream_socket_server('tcp://0.0.0.0:5000');
    while (true) {
    $response = implode("\r\n", [
    'HTTP/1.1 200 OK',
    'Content-Length: 2',
    '',
    'Hi',
    ]);
    $conn = stream_socket_accept($sock, -1);
    fwrite($conn, $response);
    }
    

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35. $s=stream_socket_server('tcp://[::1]:81');
    while($c=stream_socket_accept($s,-1))
    fwrite($c,"HTTP/1.1 200 OK\r\nContent-Length: 2\r\n\r\nHi");
    

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36. Parsing
    

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37. GET / HTTP/1.1 <--- request line
    Host: igor.io <--- header
    <--- line feed
    <--- body (blank)
    

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38. $request = implode("\r\n", [
    'GET / HTTP/1.1',
    'Host: igor.io',
    '',
    '',
    ]);
    

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39. $request = implode("\r\n", [
    'GET / HTTP/1.1',
    'Host: igor.io',
    '',
    '',
    ]);
    $expected = [
    'method' => 'GET',
    'path' => '/',
    'protocol' => 'HTTP/1.1',
    'headers' => ['Host' => 'igor.io'],
    'body' => '',
    ];
    

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40. $request = implode("\r\n", [
    'GET / HTTP/1.1',
    'Host: igor.io',
    '',
    '',
    ]);
    $expected = [
    'method' => 'GET',
    'path' => '/',
    'protocol' => 'HTTP/1.1',
    'headers' => ['Host' => 'igor.io'],
    'body' => '',
    ];
    assert($expected === parseRequest($request));
    

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41. TDD
    because edorian said so!
    

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42. function parseRequest($request)
    {
    $lines = explode("\r\n", $request);
    $requestLine = array_shift($lines);
    list($method, $path, $protocol) = explode(' ', $requestLine);
    $headers = [];
    while ($header = array_shift($lines)) {
    list($name, $value) = explode(':', $header, 2);
    $headers[trim($name)] = trim($value);
    }
    $body = array_shift($lines);
    return compact('method', 'path', 'protocol', 'headers', 'body');
    }
    

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43. HTTP/1.1 200 OK <--- status line
    Content-Length: 2 <--- headers
    <--- line feed
    Hi <--- body
    

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44. $responseSpec = [200, ['Content-Length' => '2'], 'Hi'];
    $response = implode("\r\n", [
    'HTTP/1.1 200 OK',
    'Content-Length: 2',
    '',
    'Hi',
    ]);
    assert($response === buildResponse($responseSpec));
    

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45. $responseSpec = [200, ['Content-Length' => '2'], 'Hi'];
    $response = implode("\r\n", [
    'HTTP/1.1 200 OK',
    'Content-Length: 2',
    '',
    'Hi',
    ]);
    assert($response === buildResponse($responseSpec));
    

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46. function buildResponse(array $responseSpec)
    {
    list($status, $headers, $body) = $responseSpec;
    return buildResponseStatusLine($status).
    buildResponseHeaders($headers).
    "\r\n".
    $body;
    }
    

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47. function buildResponseStatusLine($status)
    {
    $statusMap = [
    200 => 'OK',
    404 => 'Not Found',
    ];
    return "HTTP/1.1 $status {$statusMap[$status]}\r\n";
    }
    

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48. function buildResponseHeaders(array $headers)
    {
    $flatHeaders = [];
    foreach ($headers as $name => $value) {
    $flatHeaders[] = "$name: $value";
    }
    return implode("\r\n", $flatHeaders)."\r\n";
    }
    

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49. $conn = stream_socket_accept($sock, -1);
    $request = fread($conn, 512);
    $parsedRequest = parseRequest($request);
    switch ($parsedRequest['path']) {
    case '/':
    $responseSpec = [200, ['Content-Length' => 3], "Hi\n"];
    break;
    default:
    $responseSpec = [404, ['Content-Length' => 10], "Not found\n"];
    }
    fwrite($conn, buildResponse($responseSpec));
    

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50. Problem?
    • Missing error handling
    • Assumption: client closes connection
    • Assumption: request can be read in one go
    • Assumption: request no larger than 512 bytes
    • Assumption: request/response body fits in memory
    • Blocking I/O
    

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51. Asynchronous I/O
    

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52. $readable = $read ?: null;
    $writable = $write ?: null;
    $except = null;
    if (stream_select($readable, $writable, $except, 1)) {
    if ($readable) {
    foreach ($readable as $stream) {
    ...
    }
    }
    if ($writable) {
    foreach ($writable as $stream) {
    ...
    }
    }
    }
    

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53. $server = stream_socket_server('tcp://127.0.0.1:1337');
    $read = [$server];
    $write = [];
    ...
    // deep in the event loop
    foreach ($readable as $stream) {
    if ($server === $stream) {
    $conn = stream_socket_accept($server, 0);
    $read[] = $conn;
    } else {
    $data = fread($stream, 1024);
    echo $data;
    }
    }
    

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54. Event-driven, non-blocking I/O with PHP.
    

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55. $loop = React\EventLoop\Factory::create();
    $socket = new React\Socket\Server($loop);
    $http = new React\Http\Server($socket, $loop);
    $http->on('request', function ($req, $rep) {
    $rep->writeHead();
    $rep->end("Hello World!\n");
    });
    $socket->listen(8080);
    $loop->run();
    

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56. Use cases?
    

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57. github.com/igorw/webserver-talk
    

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58. Questions?
    @igorwesome
    speakerdeck.com
    /u/igorw
    nodephp.org
    

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