Unicode C++

Refresh a Dynamics CRM OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to refresh an expiring Dynamics CRM access token using the refresh token. endpoint.

(If a REST API call fails with a 401 unauthorized error, an application can auto-recover by refreshing the access token, and then re-send the request using the new token.)

Unicode C++

#include <CkJsonObjectW.h>
#include <CkDateTimeW.h>
#include <CkHttpRequestW.h>
#include <CkHttpW.h>
#include <CkHttpResponseW.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.

    // We previously obtained an access token and saved the JSON to a file using this example:
    // Get Dynamics CRM OAuth2 Access Token

    // This example will examine the JSON and expiration date, and if near expiration will
    // refresh the access token.

    CkJsonObjectW json;
    success = json.LoadFile(L"qa_data/tokens/dynamicsCrm.json");
    if (success != true) {
        return;
    }

    // The contents of the JSON look like this:
    // {
    //   "token_type": "Bearer",
    //   "scope": "user_impersonation",
    //   "expires_in": "3599",
    //   "ext_expires_in": "0",
    //   "expires_on": "1524783438",
    //   "not_before": "1524779538",
    //   "resource": "https://mydomain.api.crm.dynamics.com",
    //   "access_token": "...",
    //   "refresh_token": "...",
    //   "id_token": "..."
    // }

    // The "expires_on" value is a Unix time.
    CkDateTimeW dtExpire;
    dtExpire.SetFromUnixTime(false,json.IntOf(L"expires_on"));

    // If this date/time expires within 10 minutes of the current system time, refresh the token.

    // OK, we need to refresh the access token by sending a POST...
    // 

    CkHttpRequestW req;
    req.AddParam(L"grant_type",L"refresh_token");
    req.AddParam(L"redirect_uri",L"http://localhost:3017/");
    req.AddParam(L"client_id",L"DYNAMICS-CRM-CLIENT-ID");
    req.AddParam(L"client_secret",L"DYNAMICS-CRM-SECRET-KEY");
    req.AddParam(L"refresh_token",json.stringOf(L"refresh_token"));
    req.AddParam(L"resource",L"https://mydynamicsdomain.api.crm.dynamics.com");

    CkHttpW http;

    req.put_HttpVerb(L"POST");
    req.put_ContentType(L"application/x-www-form-urlencoded");

    CkHttpResponseW resp;
    success = http.HttpReq(L"https://login.microsoftonline.com/DYNAMICS-ENDPOINT-GUID/oauth2/token",req,resp);
    if (success == false) {
        wprintf(L"%s\n",http.lastErrorText());
        return;
    }

    // Load the JSON response.
    json.Load(resp.bodyStr());
    json.put_EmitCompact(false);

    // Show the JSON response.
    wprintf(L"%s\n",json.emit());

    wprintf(L"Response status code: %d\n",resp.get_StatusCode());

    // If the response status code is not 200, then it's an error.
    if (resp.get_StatusCode() != 200) {
        return;
    }

    // If an "expires_on" member does not exist, then add the JSON member by
    // getting the current system date/time and adding the "expires_in" seconds.
    // This way we'll know when the token expires.
    if (json.HasMember(L"expires_on") != true) {
        dtExpire.SetFromCurrentSystemTime();
        dtExpire.AddSeconds(json.IntOf(L"expires_in"));
        json.AppendString(L"expires_on",dtExpire.getAsUnixTimeStr(false));
    }

    // Save the refreshed access token JSON to a file for future requests.
    CkFileAccessW fac;
    fac.WriteEntireTextFile(L"qa_data/tokens/dynamicsCrm.json",json.emit(),L"utf-8",false);
    }