Sending emails with Net::Curl

send-email.pl6

use NativeCall;
use Net::Curl::NativeCall;
use Email::Simple;

constant EmailPassword = %*ENV<P6BUG_EMAIL_PW>;
constant FROM  = '[email protected]';
constant TO    = '[email protected]';
constant CC    = '[email protected]';
constant Email = Email::Simple.new(
  [['To', TO], ['FROM', FROM], ['CC', CC], ['Subject', 'Testing']],
  'This is a test email!'
).Str;

with curl_easy_init() {

  curl_easy_setopt($_, CURLOPT_USERNAME, FROM);
  curl_easy_setopt($_, CURLOPT_PASSWORD, EmailPassword);

  curl_easy_setopt($_, CURLOPT_URL, 'smtp://smtp.gmail.com:587');

  curl_easy_setopt($_, CURLOPT_USE_SSL, CURLUSESSL_ALL);
  curl_easy_setopt($_, CURLOPT_CAINFO, 'vendor/smtp-gmail.pem');

  curl_easy_setopt($_, CURLOPT_MAIL_FROM, FROM);
  my $recipients = curl_slist_append(curl_slist, TO);
  $recipients = curl_slist_append($recipients, CC);
  curl_easy_setopt($_, CURLOPT_MAIL_RCPT, $recipients);

  class ReadContext is repr('CStruct') {
    has int32 $lines_read;
  }

  sub memcpy(Pointer $dest, Pointer $src, size_t $n) returns Pointer is native(Str) {*}

  sub read_callback(CArray[uint8] $buffer, size_t $size, size_t $nitems, ReadContext $ctx)
      returns size_t is native() {

    return 0 if $size == 0 and $nitems == 0 and $size*$nitems < 1;

    my Str $data = Email.lines[$ctx.lines_read];

    with $data {
      my size_t $len = $_.chars;
      memcpy($buffer, $_, $len);
      $ctx.lines_read++;

      return $len;
    }

    return 0;
  }

  curl_easy_setopt($_, CURLOPT_READFUNCTION, &read_callback);

  my ReadContext $ctx .= new;
  curl_easy_setopt($_, CURLOPT_READDATA, $ctx);

  curl_easy_setopt($_, CURLOPT_VERBOSE, +True);

  my $result = curl_easy_perform($_);
  unless $result ~~ CURLE_OK {
    warn sprintf("curl_easy_perform failed: %s\n", curl_easy_strerror($result));
  }
  curl_slist_free_all($recipients);
  curl_easy_cleanup($_);
} else { warn "curl failed to initialize" }