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C

GMail SMTP Send using Previously Obtained OAuth2 Access Token

See more GMail SMTP/IMAP/POP Examples

Demonstrates how to send email using GMail and OAuth2 authentication. This example assumes an OAuth2 access token was previously obtained.

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C
#include <C_CkJsonObject.h>
#include <C_CkMailMan.h>
#include <C_CkEmail.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject json;
    const char *accessToken;
    HCkMailMan mailman;
    HCkEmail email;

    success = FALSE;

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

    //  See Get GMail SMTP Access Token 
    //  for sample code showing how to obtain a GMail SMTP access token for desktop apps.

    //  In this example, our access token was previously saved to the following file which contains JSON like this:
    //  	{
    //  	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
    //  	 "token_type": "Bearer",
    //  	 "expires_in": 3600,
    //  	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
    //  	}
    //  
    json = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(json,"qa_data/tokens/_gmailSmtp.json");
    if (success != TRUE) {
        printf("Failed to load GMail access token file.\n");
        CkJsonObject_Dispose(json);
        return;
    }

    accessToken = CkJsonObject_stringOf(json,"access_token");

    mailman = CkMailMan_Create();

    //  Set the properties for the GMail SMTP server:
    CkMailMan_putSmtpHost(mailman,"smtp.gmail.com");
    CkMailMan_putSmtpPort(mailman,587);
    CkMailMan_putStartTLS(mailman,TRUE);

    //  The SMTP username should be the GMail address of the user's account that authorized your app to send email.
    CkMailMan_putSmtpUsername(mailman,"chilkat.support@gmail.com");
    CkMailMan_putOAuth2AccessToken(mailman,accessToken);

    //  Create a new email object
    email = CkEmail_Create();

    CkEmail_putSubject(email,"This is a test");
    CkEmail_putBody(email,"This is a test");
    CkEmail_putFrom(email,"Chilkat <chilkat.support@gmail.com>");
    CkEmail_AddTo(email,"Chilkat Admin","admin@chilkatsoft.com");
    //  To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

    //  Call SendEmail to connect to the SMTP server and send.
    //  The connection (i.e. session) to the SMTP server remains
    //  open so that subsequent SendEmail calls may use the
    //  same connection.  
    success = CkMailMan_SendEmail(mailman,email);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkJsonObject_Dispose(json);
        CkMailMan_Dispose(mailman);
        CkEmail_Dispose(email);
        return;
    }

    //  You may close the connection here.  If the connection is kept open, 
    //  the next call to mailman.SendEmail will continue using the already-established connection
    //  (and automatically re-connect if needed).
    success = CkMailMan_CloseSmtpConnection(mailman);
    if (success != TRUE) {
        printf("Connection to SMTP server not closed cleanly.\n");
    }

    printf("Email Sent via GMail with OAuth2 authentication.\n");


    CkJsonObject_Dispose(json);
    CkMailMan_Dispose(mailman);
    CkEmail_Dispose(email);

    }