BLE Данные теряются при чтении характеристики, когда устройство часто отправляет данные

В итоге я написал собственную функцию отправки / кодирования электронной почты. Это хорошо сработало для отправки PDF-вложений. Я не использовал другие функции в производстве.

Примечание. Несмотря на то, что спецификация достаточно решительно, что вы должны использовать\r\n для разделения заголовков, я нашел, что это работает только тогда, когда я использовал PHP_EOL. Я тестировал это только на Linux. YMMV

<?php
# $args must be an associative array
#     required keys: from, to, body
#          body can be a string or a [tree of] associative arrays. See examples below
#     optional keys: subject, reply_to, cc, bcc
# EXAMPLES:
#    # text-only email:
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        # body will be text/plain because we're passing a string that doesn't start with '<'
#        'body' => 'Hi, testing 1 2 3',
#    ));
#
#    # html-only email
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        # body will be text/html because we're passing a string that starts with '<'
#        'body' => '<h1>Hi!</h1>I like <a href="http://cheese.com">cheese</a>',
#    ));
#
#    # text-only email (explicitly, in case first character is dynamic or something)
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        # body will be text/plain because we're passing a string that doesn't start with '<'
#        'body' => array(
#            'type' => 'text',
#            'body' => $message_text,
#        )
#    ));
#
#    # email with text and html alternatives (auto-detected mime types)
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        'body' => array(
#            'type' => 'alternatives',
#            'body' => array(
#                "Hi!\n\nI like cheese",
#                '<h1>Hi!</h1><p>I like <a href="http://cheese.com">cheese</a></p>',
#            )
#        )
#    ));
#
#    # email with text and html alternatives (explicit types)
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        'body' => array(
#            'type' => 'alternatives',
#            'body' => array(
#                array(
#                    'type' => 'text',
#                    'body' => "Hi!\n\nI like cheese",
#                ),
#                array(
#                    'type' => 'html',
#                    'body' => '<h1>Hi!</h1><p>I like cheese</p>',
#                ),
#            )
#        )
#    ));
#
#    # email with an attachment
#    email2(array(
#        'from' => 'noreply@foo.com',
#        'to' => 'jason@jasonwoof.com',
#        'subject' => 'test',
#        'body' => array(
#            'type' => 'mixed',
#            'body' => array(
#                "Hi!\n\nCheck out this (inline) image",
#                array(
#                    'type' => 'image/png',
#                    'disposition' => 'inline',
#                    'body' => $image_data, # raw file contents
#                ),
#                "Hi!\n\nAnd here's an attachment",
#                array(
#                    'type' => 'application/pdf; name="attachment.pdf"',
#                    'disposition' => 'attachment; filename="attachment.pdf"',
#                    'body' => $pdf_data, # raw file contents
#                ),
#                "Or you can use shorthand:",
#                array(
#                    'type' => 'application/pdf',
#                    'attachment' => 'attachment.pdf', # name for client (not data source)
#                    'body' => $pdf_data, # raw file contents
#                ),
#            )
#        )
#    ))
function email2($args) {
    if (!isset($args['from'])) { return 1; }
    $from = $args['from'];
    if (!isset($args['to'])) { return 2; }
    $to = $args['to'];
    $subject = isset($args['subject']) ? $args['subject'] : '';
    $reply_to = isset($args['reply_to']) ? $args['reply_to'] : '';
    $cc = isset($args['cc']) ? $args['cc'] : '';
    $bcc = isset($args['bcc']) ? $args['bcc'] : '';

    #FIXME should allow many more characters here (and do Q encoding)
    $subject = isset($args['subject']) ? $args['subject'] : '';
    $subject = preg_replace("|[^a-z0-9 _/#'.:&,-]|i", '_', $subject);

    $headers = "From: $from";
    if($reply_to) {
        $headers .= PHP_EOL . "Reply-To: $reply_to";
    }
    if($cc) {
        $headers .= PHP_EOL . "CC: $cc";
    }
    if($bcc) {
        $headers .= PHP_EOL . "BCC: $bcc";
    }

    $r = email2_helper($args['body']);
    $headers .= PHP_EOL . $r[0];
    $body = $r[1];

    if (mail($to, $subject, $body, $headers)) {
        return 0;
    } else {
        return 5;
    }
}

function email2_helper($body, $top = true) {
    if (is_string($body)) {
        if (substr($body, 0, 1) == '<') {
            return email2_helper(array('type' => 'html', 'body' => $body), $top);
        } else {
            return email2_helper(array('type' => 'text', 'body' => $body), $top);
        }
    }
    # now we can assume $body is an associative array
    # defaults:
    $type = 'application/octet-stream';
    $mime = false;
    $boundary = null;
    $disposition = null;
    $charset = false;
    # process 'type' first, because it sets defaults for others
    if (isset($body['type'])) {
        $type = $body['type'];
        if ($type === 'text') {
            $type = 'text/plain';
            $charset = true;
        } elseif ($type === 'html') {
            $type = 'text/html';
            $charset = true;
        } elseif ($type === 'alternative' || $type === 'alternatives') {
            $mime = true;
            $type = 'multipart/alternative';
        } elseif ($type === 'mixed') {
            $mime = true;
            $type = 'multipart/mixed';
        }
    }
    if (isset($body['disposition'])) {
        $disposition = $body['disposition'];
    }
    if (isset($body['attachment'])) {
        if ($disposition == null) {
            $disposition = 'attachment';
        }
        $disposition .= "; filename=\"{$body['attachment']}\"";
        $type .= "; name=\"{$body['attachment']}\"";
    }
    # make headers
    $headers = array();
    if ($top && $mime) {
        $headers[] = 'MIME-Version: 1.0';
    }
    if ($mime) {
        $boundary = md5('5sd^%Ca)~aAfF0=4mIN' . rand() . rand());
        $type .= "; boundary=$boundary";
    }
    if ($charset) {
        $type .= '; charset=' . (isset($body['charset']) ? $body['charset'] : 'UTF-8');
    }
    $headers[] = "Content-Type: $type";
    if ($disposition !== null) {
        $headers[] = "Content-Disposition: {$disposition}";
    }

    $data = '';
    # return array, first el is headers, 2nd is body (php's mail() needs them separate)
    if ($mime) {
        foreach ($body['body'] as $sub_body) {
            $data .= "--$boundary" . PHP_EOL;
            $r = email2_helper($sub_body, false);
            $data .= $r[0] . PHP_EOL . PHP_EOL; # headers
            $data .= $r[1] . PHP_EOL . PHP_EOL; # body
        }
        $data .= "--$boundary--";
    } else {
        if(preg_match('/[^\x09\x0A\x0D\x20-\x7E]/', $body['body'])) {
            $headers[] = "Content-Transfer-Encoding: base64";
            $data .= chunk_split(base64_encode($body['body']));
        } else {
            $data .= $body['body'];
        }
    }
    return array(join(PHP_EOL, $headers), $data);
}