Sending mail with attachment

How to send a email with attachment using gmail api? am able to send mail successfully without an attachment,but am not getting how to attach a file and send the mail…can anyone please help me on this .

following is the snippet am using for sending a mail with out attachment

function sendMessage(auth) {
    var gmail =google.gmail('v1');

    var email_lines =[];
    email_lines.push("From: [e-mail]");
    email_lines.push("To:[e-mail] ");
    email_lines.push('Content-type: text/html;charset=iso-8859-1');
    email_lines.push('MIME-Version: 1.0');
    email_lines.push("Subject: Testing ");
    email_lines.push("");
    email_lines.push("hai");
    email_lines.push("<b>And henge naavu</b>");

    var email =email_lines.join("\r\n").trim();

    var base64EncodedEmail = new Buffer(email).toString('base64');

  base64EncodedEmail= base64EncodedEmail.replace(/\//g,'_').replace(/\+/g,'-');

  gmail.users.messages.send({
     auth:auth,
    'userId': 'me',

 'resource': {
        'raw': base64EncodedEmail
      }

  },function(err, response) {
    if (err) {
      console.log('The API returned an error: ' + err);
      return;
    }
 console.log(response);
});

Thanks in advance

[ishwarrimal]

Here is the solution that worked for me,

function makeBody(subject, message) { var boundary = "__myapp__"; var nl = “\n”; var attach = new Buffer(fs.readFileSync(__dirname + “/…/”+fileName)) .toString(“base64”); // console.dir(attach); var str = [

        "MIME-Version: 1.0",
        "Content-Transfer-Encoding: 7bit",
        "to: " + receiverId,
        "subject: " + subject,
        "Content-Type: multipart/alternate; boundary=" + boundary + nl,
        "--" + boundary,
        "Content-Type: text/plain; charset=UTF-8",
        "Content-Transfer-Encoding: 7bit" + nl,
        message+ nl,
        "--" + boundary,
        "--" + boundary,
        "Content-Type: Application/pdf; name=myPdf.pdf",
        'Content-Disposition: attachment; filename=myPdf.pdf',
        "Content-Transfer-Encoding: base64" + nl,
        attach,
        "--" + boundary + "--"

    ].join("\n");

    var encodedMail = new Buffer(str).toString("base64").replace(/\+/g, '-').replace(/\//g, '_');
    return encodedMail;
}

[ir-fuel]

Why isn’t there an example of such basic functionality anywhere? I’ve been spending 4 hours trying to send a mail with an attachment. Impossible.