(MFC) Dropbox Refresh OAuth2 Access Token

See more Dropbox Examples

Demonstrates how to mint a new access token using the refresh token obtained when originally getting the OAuth2 access token.

For more information, see https://www.dropbox.com/developers/documentation/http/documentation

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkHttp.h>
#include <CkJsonObject.h>
#include <CkHttpRequest.h>
#include <CkHttpResponse.h>
#include <CkStringBuilder.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkHttp http;
    bool success;

    http.put_SessionLogFilename("qa_output/sessionLog.txt");

    // Implements the following CURL command:

    // curl -X GET https://api.dropbox.com/oauth2/token \
    //     -d grant_type=refresh_token \
    //     -d refresh_token=<YOUR_REFRESH_TOKEN> \
    //     -u <YOUR_APP_KEY>:<YOUR_APP_SECRET>

    // Use the following online tool to generate HTTP code from a CURL command
    // Convert a cURL Command to HTTP Source Code

    http.put_Login("DROPBOX_APP_KEY");
    http.put_Password("DROPBOX_APP_SECRET");

    // Get the refresh token from the JSON we saved when originally getting the access token.
    // (See Get Dropbox OAuth2 Access Token w/ Refresh Token
    CkJsonObject json;
    success = json.LoadFile("qa_data/tokens/dropbox.json");
    if (success == false) {
        strOut.append(json.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkHttpRequest req;
    req.AddParam("grant_type","refresh_token");
    req.AddParam("refresh_token",json.stringOf("refresh_token"));

    CkHttpResponse *resp = http.PostUrlEncoded("https://api.dropbox.com/oauth2/token",req);
    if (http.get_LastMethodSuccess() == false) {
        strOut.append(http.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkStringBuilder sbResponseBody;
    resp->GetBodySb(sbResponseBody);

    CkJsonObject jResp;
    jResp.LoadSb(sbResponseBody);
    jResp.put_EmitCompact(false);

    strOut.append("Response Body:");
    strOut.append("\r\n");
    strOut.append(jResp.emit());
    strOut.append("\r\n");

    int respStatusCode = resp->get_StatusCode();
    strOut.append("Response Status Code = ");
    strOut.appendInt(respStatusCode);
    strOut.append("\r\n");
    if (respStatusCode >= 400) {
        strOut.append("Response Header:");
        strOut.append("\r\n");
        strOut.append(resp->header());
        strOut.append("\r\n");
        strOut.append("Failed.");
        strOut.append("\r\n");
        delete resp;
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    delete resp;

    // Sample JSON response:
    // (Sample code for parsing the JSON response is shown below)

    // {
    //   "access_token": "sl.AC75WPYRqOi0mxcRqlimbV9FKHu04biz5qHwatG3MTgzFK7kLrGVlM9EgP4603tE7bWw0s1rMbTKiHsf37TUshPYvq-3r0qeBr_PrZIAibN8XOQicvboiOnqx6JrDekq-w8D-tE",
    //   "token_type": "bearer",
    //   "expires_in": 14400
    // }

    const char *access_token = jResp.stringOf("access_token");
    strOut.append("New Access Token: ");
    strOut.append(access_token);
    strOut.append("\r\n");

    // Perhaps update our Dropbox JSON file with the new access token.
    // (The existing refresh token does not change, and can be used over and over to mint new access tokens.)
    json.UpdateString("access_token",access_token);

    json.WriteFile("qa_data/tokens/dropbox.json");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }