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POP3 GMail XOAUTH2 Authentication

See more GMail SMTP/IMAP/POP Examples

Demonstrates using OAuth2 authentication with pop.gmail.com.

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

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

void ChilkatSample(void)
    {
    bool success = false;

    // 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;
    success = jsonToken.LoadFile("qa_data/tokens/gmail_pop3.json");
    if (success == false) {
        std::cout << jsonToken.lastErrorText() << "\r\n";
        return;
    }

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

    // Make the TLS connection to the POP3 server.
    success = mailman.Pop3Connect();
    if (success != true) {
        std::cout << mailman.lastErrorText() << "\r\n";
        return;
    }

    // Authenticate..
    success = mailman.Pop3Authenticate();
    if (success != true) {
        std::cout << mailman.lastErrorText() << "\r\n";
        return;
    }

    // Find out how many emails are on the server..
    int numEmails = mailman.CheckMail();
    if (numEmails < 0) {
        std::cout << mailman.lastErrorText() << "\r\n";
        return;
    }

    // Examine the POP3 session log:
    std::cout << mailman.pop3SessionLog() << "\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) {
        std::cout << mailman.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "-- Finished." << "\r\n";
    }