(MFC) GeoOp Exchange Refresh Token for New Access Token

Demonstrates how to use the /oauth2/token endpoint to exchange it for a new access token once the current access token has expired.

Note: This example requires Chilkat v9.5.0.65 or greater.

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

See Also: Using MFC CString in Chilkat

#include <CkJsonObject.h>
#include <CkRest.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    // This example also assumes that OAuth2 access and refresh tokens were previously fetched.
    // and saved in a JSON file.  

    // First get our previously obtained refresh token.
    // { .... "refresh_token":"e6dqdG....mzjpT04w==", .... }
    CkJsonObject jsonToken;
    bool success = jsonToken.LoadFile("qa_data/tokens/geoop.json");

    CkRest rest;

    // Connect to GeoOp...
    bool bAutoReconnect = true;
    success = rest.Connect("login.geoop.com",443,true,bAutoReconnect);
    if (success != true) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Set the X-Version header.
    rest.AddHeader("X-Version","1.0");

    // Provide the required form params to get the new access token
    strOut.append("refresh_token = ");
    strOut.append(jsonToken.stringOf("refresh_token"));
    strOut.append("\r\n");
    rest.AddQueryParam("refresh_token",jsonToken.stringOf("refresh_token"));
    rest.AddQueryParam("grant_type","refresh_token");
    rest.AddQueryParam("client_id","GEOOP-CLIENT-ID");
    rest.AddQueryParam("client_secret","GEOOP-CLIENT-SECRET");

    const char *responseBody = rest.fullRequestFormUrlEncoded("POST","/oauth2/token");
    if (rest.get_LastMethodSuccess() != true) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // If the response status code did not indicate success, then see what happened..
    if (rest.get_ResponseStatusCode() != 200) {
        strOut.append("Request Header: ");
        strOut.append("\r\n");
        strOut.append(rest.lastRequestHeader());
        strOut.append("\r\n");
        strOut.append("----");
        strOut.append("\r\n");
        strOut.append("Response StatusCode = ");
        strOut.appendInt(rest.get_ResponseStatusCode());
        strOut.append("\r\n");
        strOut.append("Response StatusLine: ");
        strOut.append(rest.responseStatusText());
        strOut.append("\r\n");
        strOut.append("Response Header:");
        strOut.append("\r\n");
        strOut.append(rest.responseHeader());
        strOut.append("\r\n");
        strOut.append(responseBody);
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkJsonObject json;
    json.put_EmitCompact(false);
    json.Load(responseBody);

    // Show the full JSON response.  It should contain the new access token...
    strOut.append(json.emit());
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }