(Node.js) GMail SMTP Send using Previously Obtained OAuth2 Access Token

Demonstrates how to send email using GMail and OAuth2 authentication. This example assumes an OAuth2 access token was previously obtained.

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // See Get GMail SMTP Access Token 
    // for sample code showing how to obtain a GMail SMTP access token for desktop apps.

    // In this example, our access token was previously saved to the following file which contains JSON like this:
    // 	{
    // 	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
    // 	 "token_type": "Bearer",
    // 	 "expires_in": 3600,
    // 	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
    // 	}
    // 
    var json = new chilkat.JsonObject();
    var success = json.LoadFile("qa_data/tokens/_gmailSmtp.json");
    if (success !== true) {
        console.log("Failed to load GMail access token file.");
        return;
    }

    var accessToken = json.StringOf("access_token");

    var mailman = new chilkat.MailMan();

    // Set the properties for the GMail SMTP server:
    mailman.SmtpHost = "smtp.gmail.com";
    mailman.SmtpPort = 587;
    mailman.StartTLS = true;

    // The SMTP username should be the GMail address of the user's account that authorized your app to send email.
    mailman.SmtpUsername = "chilkat.support@gmail.com";
    mailman.OAuth2AccessToken = accessToken;

    // Create a new email object
    var email = new chilkat.Email();

    email.Subject = "This is a test";
    email.Body = "This is a test";
    email.From = "Chilkat <chilkat.support@gmail.com>";
    email.AddTo("Chilkat Admin","admin@chilkatsoft.com");
    // To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

    // Call SendEmail to connect to the SMTP server and send.
    // The connection (i.e. session) to the SMTP server remains
    // open so that subsequent SendEmail calls may use the
    // same connection.  
    success = mailman.SendEmail(email);
    if (success !== true) {
        console.log(mailman.LastErrorText);
        return;
    }

    // You may close the connection here.  If the connection is kept open, 
    // the next call to mailman.SendEmail will continue using the already-established connection
    // (and automatically re-connect if needed).
    success = mailman.CloseSmtpConnection();
    if (success !== true) {
        console.log("Connection to SMTP server not closed cleanly.");
    }

    console.log("Email Sent via GMail with OAuth2 authentication.");

}

chilkatExample();