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Unicode C

Google Drive Refresh Access Token

See more Google Drive Examples

Demonstrates how to automatically refresh the access token when it expires.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkJsonObjectW.h>
#include <C_CkOAuth2W.h>
#include <C_CkFileAccessW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObjectW json;
    const wchar_t *tokenFilePath;
    HCkOAuth2W oauth2;
    HCkFileAccessW fac;

    success = FALSE;

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

    success = TRUE;

    // This example uses a previously obtained access token having permission for the 
    // Google Drive scope.

    // The access token (and refresh token) was previously saved to a JSON file with this format:
    // See Get Google Drive OAuth2 Access Token

    // {
    //   "access_token": "ya29.Gls-BsdxTWuenChv ... yzVIrXikkLxu5T6dy4I6GjADFardoz4Lruw",
    //   "expires_in": 3600,
    //   "refresh_token": "1/tMBJ ... 27D-Hk6rpQYBA",
    //   "scope": "https://www.googleapis.com/auth/drive",
    //   "token_type": "Bearer"
    // }

    json = CkJsonObjectW_Create();
    tokenFilePath = L"qa_data/tokens/googleDrive.json";
    CkJsonObjectW_LoadFile(json,tokenFilePath);

    oauth2 = CkOAuth2W_Create();
    CkOAuth2W_putAccessToken(oauth2,CkJsonObjectW_stringOf(json,L"access_token"));
    CkOAuth2W_putRefreshToken(oauth2,CkJsonObjectW_stringOf(json,L"refresh_token"));

    CkOAuth2W_putAuthorizationEndpoint(oauth2,L"https://accounts.google.com/o/oauth2/v2/auth");
    CkOAuth2W_putTokenEndpoint(oauth2,L"https://www.googleapis.com/oauth2/v4/token");

    //  Replace these with actual values.
    CkOAuth2W_putClientId(oauth2,L"GOOGLE-CLIENT-ID");
    CkOAuth2W_putClientSecret(oauth2,L"GOOGLE-CLIENT-SECRET");
    CkOAuth2W_putScope(oauth2,L"https://www.googleapis.com/auth/drive");

    // Use OAuth2 to refresh the access token.
    success = CkOAuth2W_RefreshAccessToken(oauth2);
    if (success != TRUE) {
        wprintf(L"%s\n",CkOAuth2W_lastErrorText(oauth2));
        CkJsonObjectW_Dispose(json);
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    wprintf(L"%s\n",CkOAuth2W_accessTokenResponse(oauth2));

    // Save the new access token to our JSON file (so we can refresh it again when needed).
    CkJsonObjectW_UpdateString(json,L"access_token",CkOAuth2W_accessToken(oauth2));

    fac = CkFileAccessW_Create();
    CkFileAccessW_WriteEntireTextFile(fac,tokenFilePath,CkJsonObjectW_emit(json),L"utf-8",FALSE);

    wprintf(L"Access Token Refreshed!\n");


    CkJsonObjectW_Dispose(json);
    CkOAuth2W_Dispose(oauth2);
    CkFileAccessW_Dispose(fac);

    }