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Unicode C

Get Google API Access Token using P12 Service Account Key

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Demonstrates how to get a Google API access token using a P12 service account key.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkPfxW.h>
#include <C_CkAuthGoogleW.h>
#include <C_CkSocketW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPfxW pfx;
    HCkAuthGoogleW gAuth;
    const wchar_t *iss;
    const wchar_t *scope;
    const wchar_t *oauth_sub;
    int numSec;
    HCkSocketW tlsSock;

    success = FALSE;

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

    // --------------------------------------------------------------------------------
    // For a step-by-step guide for setting up your Google Workspace service account,
    // see Setup Google Workspace Account for Sending SMTP GMail from a Service Account
    // --------------------------------------------------------------------------------

    // First load the PKCS12 (.p12 / .pfx) into a PFX object.
    pfx = CkPfxW_Create();
    success = CkPfxW_LoadPfxFile(pfx,L"qa_data/pfx/chilkat25-cbd7b42afbd8.p12",L"notasecret");
    if (success != TRUE) {
        wprintf(L"%s\n",CkPfxW_lastErrorText(pfx));
        CkPfxW_Dispose(pfx);
        return;
    }

    gAuth = CkAuthGoogleW_Create();
    success = CkAuthGoogleW_SetP12(gAuth,pfx);

    // The ISS is your service account email address ending in gserviceaccount.com.
    iss = L"chilkatsvc@chilkat25.iam.gserviceaccount.com";

    // The scope is always the following string:
    scope = L"https://mail.google.com/";

    // The sub is your company email address
    oauth_sub = L"info@chilkat.xyz";

    // The access token is valid for this number of seconds.
    numSec = 3600;

    CkAuthGoogleW_putEmailAddress(gAuth,iss);
    CkAuthGoogleW_putScope(gAuth,scope);
    CkAuthGoogleW_putExpireNumSeconds(gAuth,numSec);
    CkAuthGoogleW_putSubEmailAddress(gAuth,oauth_sub);

    // Connect to www.googleapis.com
    tlsSock = CkSocketW_Create();
    success = CkSocketW_Connect(tlsSock,L"www.googleapis.com",443,TRUE,5000);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSocketW_lastErrorText(tlsSock));
        CkPfxW_Dispose(pfx);
        CkAuthGoogleW_Dispose(gAuth);
        CkSocketW_Dispose(tlsSock);
        return;
    }

    // Send the request to obtain the access token.
    success = CkAuthGoogleW_ObtainAccessToken(gAuth,tlsSock);
    if (success != TRUE) {
        wprintf(L"%s\n",CkAuthGoogleW_lastErrorText(gAuth));
        CkPfxW_Dispose(pfx);
        CkAuthGoogleW_Dispose(gAuth);
        CkSocketW_Dispose(tlsSock);
        return;
    }

    // Examine the access token:
    wprintf(L"Access Token: %s\n",CkAuthGoogleW_accessToken(gAuth));


    CkPfxW_Dispose(pfx);
    CkAuthGoogleW_Dispose(gAuth);
    CkSocketW_Dispose(tlsSock);

    }