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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 C Downloads

C
#include <C_CkFileAccess.h>
#include <C_CkAuthGoogle.h>
#include <C_CkSocket.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkFileAccess fac;
    const char *jsonKey;
    HCkAuthGoogle gAuth;
    HCkSocket 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 = CkFileAccess_Create();
    jsonKey = CkFileAccess_readEntireTextFile(fac,"qa_data/googleSvcAccountKeys/ChilkatCloud-48f7737c7505.json","utf-8");
    if (CkFileAccess_getLastMethodSuccess(fac) != TRUE) {
        printf("%s\n",CkFileAccess_lastErrorText(fac));
        CkFileAccess_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 = CkAuthGoogle_Create();
    CkAuthGoogle_putJsonKey(gAuth,jsonKey);

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

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

    CkAuthGoogle_putSubEmailAddress(gAuth,"");

    // Connect to www.googleapis.com using TLS
    tlsSock = CkSocket_Create();
    success = CkSocket_Connect(tlsSock,"www.googleapis.com",443,TRUE,5000);
    if (success != TRUE) {
        printf("%s\n",CkSocket_lastErrorText(tlsSock));
        CkFileAccess_Dispose(fac);
        CkAuthGoogle_Dispose(gAuth);
        CkSocket_Dispose(tlsSock);
        return;
    }

    // Send the request to obtain the access token.
    success = CkAuthGoogle_ObtainAccessToken(gAuth,tlsSock);
    if (success != TRUE) {
        printf("%s\n",CkAuthGoogle_lastErrorText(gAuth));
        CkFileAccess_Dispose(fac);
        CkAuthGoogle_Dispose(gAuth);
        CkSocket_Dispose(tlsSock);
        return;
    }

    // Examine the access token:
    printf("Access Token: %s\n",CkAuthGoogle_accessToken(gAuth));

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


    CkFileAccess_Dispose(fac);
    CkAuthGoogle_Dispose(gAuth);
    CkSocket_Dispose(tlsSock);

    }