ソケットでHTTP/1.1通信する

socket-http.php

<?php

$request = implode("\r\n", [
    'POST /post HTTP/1.1',
    'Host: httpbin.org',
    'Accept: application/json',
    'Content-Type: application/json',
    'Connection: close',
    '',
    json_encode(['foo' => 'bar']),
]);

$ip = dns_get_record('httpbin.org', DNS_A)[0]['ip'];

$sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_connect($sock, $ip, 80) or die(socket_strerror(socket_last_error()));

echo $request, "\n\n------------------------------\n\n";

socket_write($sock, $request);

$response = '';
do {
    $response .= ($buf = socket_read($sock, 2048));
} while ($buf !== '');

socket_close($sock);

echo $response;