(Go) Send GMail with Attachments

Demonstrates how to send an email containing attachments using the GMail REST API.

Chilkat Go Downloads

Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

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

    var success bool

    // Use the Chilkat Email API to create or load an email.
    email := chilkat.NewEmail()

    // The From name/address don't need to be specified. 
    // GMail will automatically use your Gmail address if the following 2 lines are omitted.
    email.SetFromName("My Name")
    email.SetFromAddress("my_account_name@gmail.com")

    email.AddTo("John Smith","somebody@somewhere.com")
    // To add more recipients, make additional calls to AddTo or AddCC, one per recipient...

    email.SetSubject("This is a test GMail email created using Chilkat.")
    email.SetCharset("utf-8")
    email.AddPlainTextAlternativeBody("This is a test")

    // Create an HTML email body with an embedded image.
    cid := email.AddRelatedFile("qa_data/jpg/starfish.jpg")
    sbHtml := chilkat.NewStringBuilder()
    sbHtml.Append("<html><body>This is a <b>test</b><br><img src=\"cid:STARFISH_CID\"/></body></html>")
    numReplacements := sbHtml.Replace("STARFISH_CID",*cid)

    email.AddHtmlAlternativeBody(*sbHtml.GetAsString())

    // Add some attachments..
    mimeType := email.AddFileAttachment("qa_data/helloWorld.pdf")
    if email.LastMethodSuccess() != true {
        fmt.Println("Failed to add PDF attachment.")
        email.DisposeEmail()
        sbHtml.DisposeStringBuilder()
        return
    }

    mimeType = email.AddFileAttachment("qa_data/msword/sample2.docx")
    if email.LastMethodSuccess() != true {
        fmt.Println("Failed to add MS-Word attachment.")
        email.DisposeEmail()
        sbHtml.DisposeStringBuilder()
        return
    }

    // OK.. we now have an HTML email with 2 attachments..
    sbMime := chilkat.NewStringBuilder()
    email.GetMimeSb(sbMime)

    // Send the email.  (GMail has a 5MB limit on the total email size.)
    http := chilkat.NewHttp()
    http.SetAuthToken("GMAIL-ACCESS-TOKEN")

    // Send using the simple upload request for the Gmail API
    url := "https://www.googleapis.com/upload/gmail/v1/users/me/messages/send?uploadType=media"
    sendGzipped := true
    resp := http.PTextSb("POST",url,sbMime,"utf-8","message/rfc822",false,sendGzipped)
    if http.LastMethodSuccess() != true {
        fmt.Println(http.LastErrorText())
        email.DisposeEmail()
        sbHtml.DisposeStringBuilder()
        sbMime.DisposeStringBuilder()
        http.DisposeHttp()
        return
    }

    // A status code of 200 indicates success.
    fmt.Println("Response status code: ", resp.StatusCode())
    fmt.Println("Response body:")
    fmt.Println(resp.BodyStr())
    resp.DisposeHttpResponse()

    // The response body contains JSON.
    // Use the online tool at Generate JSON Parsing Code
    // to generate JSON parsing code.

    // A sample successful JSON response:

    // {
    //  "id": "166f0d4ac39e50bf",
    //  "threadId": "166f0d4ac39e50bf",
    //  "labelIds": [
    //   "SENT"
    //  ]
    // }

    email.DisposeEmail()
    sbHtml.DisposeStringBuilder()
    sbMime.DisposeStringBuilder()
    http.DisposeHttp()