(MFC) POP3 GMail XOAUTH2 Authentication

Demonstrates using OAuth2 authentication with pop.gmail.com.

Note: This example requires Chilkat v9.5.0.83 or greater.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkMailMan.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkMailMan mailman;

    mailman.put_MailHost("pop.gmail.com");
    mailman.put_MailPort(995);
    mailman.put_PopSsl(true);

    mailman.put_PopUsername("my_account@gmail.com");

    // If using OAuth2 authentication, leave the password empty.
    mailman.put_PopPassword("");

    // Load our previously obtained OAuth2 access token.
    // See Getting a GMail POP3 OAuth2 Access Token
    CkJsonObject jsonToken;
    bool success = jsonToken.LoadFile("qa_data/tokens/gmail_pop3.json");
    if (success == false) {
        strOut.append(jsonToken.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    mailman.put_OAuth2AccessToken(jsonToken.stringOf("access_token"));

    // Make the TLS connection to the POP3 server.
    success = mailman.Pop3Connect();
    if (success != true) {
        strOut.append(mailman.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Authenticate..
    success = mailman.Pop3Authenticate();
    if (success != true) {
        strOut.append(mailman.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Find out how many emails are on the server..
    int numEmails = mailman.CheckMail();
    if (numEmails < 0) {
        strOut.append(mailman.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Examine the POP3 session log:
    strOut.append(mailman.pop3SessionLog());
    strOut.append("\r\n");

    // The POP3 session log will look something like this:

    // **** Connected to pop.gmail.com:995
    // < +OK Gpop ready for requests from 87.9.200.42 l16mb86351205iok
    // > AUTH XOAUTH2 dXNlcj1....VaMDJFAQE=
    // < +OK Welcome.
    // > STAT
    // < +OK 301 1627357
    // 
    // -- Finished.

    // End the POP3 session and close the connection to the GMail server.
    success = mailman.Pop3EndSession();
    if (success != true) {
        strOut.append(mailman.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    strOut.append("-- Finished.");
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }