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Go

SMTP Inspection

See more SMTP Examples

Examine an SMTP session to view all communications sent to the SMTP server.

Chilkat Go Downloads

Go
    success := false

    mailman := chilkat.NewMailMan()

    mailman.SetSmtpHost("smtp.example.com")
    mailman.SetSmtpUsername("myUsername")
    mailman.SetSmtpPassword("myPassword")

    mailman.SetSmtpPort(465)
    mailman.SetStartTLS(true)

    email := chilkat.NewEmail()

    email.SetSubject("This is a test")
    email.SetBody("This is a test")
    email.SetFrom("Alex <alex@example.com>")
    email.AddTo("Christoph","christoph@example2.com")
    email.AddBcc("Victor","victor@example3.com")

    // Generate the MIME that is sent when SendEmail is called
    mimeStr := mailman.RenderToMime(email)
    fmt.Println(*mimeStr)

    success = mailman.SendEmail(email)
    if success == false {
        fmt.Println(mailman.LastErrorText())
        mailman.DisposeMailMan()
        email.DisposeEmail()
        return
    }

    success = mailman.CloseSmtpConnection()
    if success != true {
        fmt.Println("Connection to SMTP server not closed cleanly.")
    }

    // Examine the SMTP session log.
    fmt.Println("----")
    fmt.Println("Smtp Session Log:")
    fmt.Println(mailman.SmtpSessionLog())

    // ---------------------------------------------------
    // Sample output:
    // ---------------------------------------------------

    // MIME-Version: 1.0
    // Date: Fri, 06 Mar 2026 16:21:00 -0600
    // Message-ID: <A5DC25990C93EC2676F4FBB2BB3BFA9EB34FF9D3@CHILKAT25>
    // Content-Type: text/plain; charset=us-ascii; format=flowed
    // Content-Transfer-Encoding: 7bit
    // X-Priority: 3 (Normal)
    // Subject: This is a test
    // From: Alex <alex@example.com>
    // To: Christoph <christoph@example2.com>
    // Bcc: Victor <victor@example3.com>
    // 
    // This is a test
    // ----
    // Smtp Session Log:
    // 220 smtp.example.com ESMTP Amazon WorkMail SMTP Service
    // EHLO MYCOMPUTER<CRLF>
    // 250-smtp.example.com
    // 250-8BITMIME
    // 250-AUTH PLAIN LOGIN
    // 250 Ok
    // AUTH LOGIN<CRLF>
    // 334 VXNlcm5hbWU6
    // YWRtaW5AY2hpbGthdHNvZnQuY29t<CRLF>
    // 334 UGFzc3dvcmQ6
    // {PasswordOrCredentials}
    // 235 Authentication successful.
    // MAIL FROM:<alex@example.com><CRLF>
    // 250 Ok
    // RCPT TO:<christoph@example2.com><CRLF>
    // 250 Ok
    // RCPT TO:<victor@example3.com><CRLF>
    // 250 Ok
    // DATA<CRLF>
    // 354 End data with <CR><LF>.<CR><LF>
    // {388 bytes} <--- The MIME source of the email (examined via RenderToMime) was sent here.
    // <CRLF>.<CRLF>
    // 250 Ok
    // QUIT<CRLF>
    // 221 Bye

    mailman.DisposeMailMan()
    email.DisposeEmail()