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Objective-C

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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Objective-C
#import <CkoMailMan.h>
#import <CkoJsonObject.h>

BOOL success = NO;

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

CkoMailMan *mailman = [[CkoMailMan alloc] init];

mailman.MailHost = @"pop.gmail.com";
mailman.MailPort = [NSNumber numberWithInt:995];
mailman.PopSsl = YES;

mailman.PopUsername = @"my_account@gmail.com";

//  If using OAuth2 authentication, leave the password empty.
mailman.PopPassword = @"";

//  Load our previously obtained OAuth2 access token.
//  See Getting a GMail POP3 OAuth2 Access Token
CkoJsonObject *jsonToken = [[CkoJsonObject alloc] init];
success = [jsonToken LoadFile: @"qa_data/tokens/gmail_pop3.json"];
if (success == NO) {
    NSLog(@"%@",jsonToken.LastErrorText);
    return;
}

mailman.OAuth2AccessToken = [jsonToken StringOf: @"access_token"];

//  Make the TLS connection to the POP3 server.
success = [mailman Pop3Connect];
if (success != YES) {
    NSLog(@"%@",mailman.LastErrorText);
    return;
}

//  Authenticate..
success = [mailman Pop3Authenticate];
if (success != YES) {
    NSLog(@"%@",mailman.LastErrorText);
    return;
}

//  Find out how many emails are on the server..
int numEmails = [[mailman CheckMail] intValue];
if (numEmails < 0) {
    NSLog(@"%@",mailman.LastErrorText);
    return;
}

//  Examine the POP3 session log:
NSLog(@"%@",mailman.Pop3SessionLog);

//  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 != YES) {
    NSLog(@"%@",mailman.LastErrorText);
    return;
}

NSLog(@"%@",@"-- Finished.");