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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 <CkJsonObjectW.h>
#include <CkOAuth2W.h>
#include <CkFileAccessW.h>

void ChilkatSample(void)
    {
    bool 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"
    // }

    CkJsonObjectW json;
    const wchar_t *tokenFilePath = L"qa_data/tokens/googleDrive.json";
    json.LoadFile(tokenFilePath);

    CkOAuth2W oauth2;
    oauth2.put_AccessToken(json.stringOf(L"access_token"));
    oauth2.put_RefreshToken(json.stringOf(L"refresh_token"));

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

    //  Replace these with actual values.
    oauth2.put_ClientId(L"GOOGLE-CLIENT-ID");
    oauth2.put_ClientSecret(L"GOOGLE-CLIENT-SECRET");
    oauth2.put_Scope(L"https://www.googleapis.com/auth/drive");

    // Use OAuth2 to refresh the access token.
    success = oauth2.RefreshAccessToken();
    if (success != true) {
        wprintf(L"%s\n",oauth2.lastErrorText());
        return;
    }

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

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

    CkFileAccessW fac;
    fac.WriteEntireTextFile(tokenFilePath,json.emit(),L"utf-8",false);

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