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Unicode C

Get Access Token for Google Tasks using Service Account JSON Key

See more Google Tasks Examples

Demonstrates how to get an access token for the Google Tasks API using a Service Account JSON key.

Chilkat Unicode C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkFileAccessW fac;
    const wchar_t *jsonKey;
    HCkAuthGoogleW gAuth;
    HCkSocketW tlsSock;

    success = FALSE;

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

    // First load the JSON key into a string.
    fac = CkFileAccessW_Create();
    jsonKey = CkFileAccessW_readEntireTextFile(fac,L"qa_data/googleSvcAccountKeys/ChilkatCloud-48f7737c7505.json",L"utf-8");
    if (CkFileAccessW_getLastMethodSuccess(fac) != TRUE) {
        wprintf(L"%s\n",CkFileAccessW_lastErrorText(fac));
        CkFileAccessW_Dispose(fac);
        return;
    }

    // A JSON private key should look like this:

    // {
    //   "type": "service_account",
    //   "project_id": "chilkatcloud",
    //   "private_key_id": "48f7737c7505bb88eee6a20d09993e10605d466e",
    //   "private_key": "-----BEGIN PRIVATE KEY----- ... -----END PRIVATE KEY-----\n",
    //   "client_email": "pip-564@chilkatcloud.iam.gserviceaccount.com",
    //   "client_id": "109982228323456925225",
    //   "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    //   "token_uri": "https://oauth2.googleapis.com/token",
    //   "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    //   "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/pip-564%40chilkatcloud.iam.gserviceaccount.com"
    // }

    gAuth = CkAuthGoogleW_Create();
    CkAuthGoogleW_putJsonKey(gAuth,jsonKey);

    // Choose the scope for read/write access.
    CkAuthGoogleW_putScope(gAuth,L"https://www.googleapis.com/auth/tasks");

    // Request an access token that is valid for this many seconds.
    CkAuthGoogleW_putExpireNumSeconds(gAuth,3600);

    CkAuthGoogleW_putSubEmailAddress(gAuth,L"");

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

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

    // Save our access token to a file.
    success = CkFileAccessW_WriteEntireTextFile(fac,L"qa_data/tokens/googleTasks.txt",CkAuthGoogleW_accessToken(gAuth),L"utf-8",FALSE);


    CkFileAccessW_Dispose(fac);
    CkAuthGoogleW_Dispose(gAuth);
    CkSocketW_Dispose(tlsSock);

    }