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Azure REST API Access Token

See more Azure OAuth2 Examples

Demonstrates how to request an Azure REST API OAUTH2 access token.

Note: In order to access resources a Service Principal needs to be created in your Tenant. It is really convenient to do it via AZ CLI:

az ad sp create-for-rbac --name [APP_NAME] --password [CLIENT_SECRET]

Chilkat Unicode C Downloads

Unicode C
#include <C_CkRestW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRestW rest;
    BOOL bTls;
    int port;
    BOOL bAutoReconnect;
    const wchar_t *strResponseBody;
    int respStatusCode;
    HCkJsonObjectW json;

    success = FALSE;

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

    rest = CkRestW_Create();

    // URL: https://login.microsoftonline.com/TENANT_ID/oauth2/token
    bTls = TRUE;
    port = 443;
    bAutoReconnect = TRUE;
    success = CkRestW_Connect(rest,L"login.microsoftonline.com",port,bTls,bAutoReconnect);
    if (success != TRUE) {
        wprintf(L"ConnectFailReason: %d\n",CkRestW_getConnectFailReason(rest));
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        return;
    }

    // Add query params to the request.
    CkRestW_AddQueryParam(rest,L"grant_type",L"client_credentials");
    CkRestW_AddQueryParam(rest,L"client_id",L"APP_ID");
    CkRestW_AddQueryParam(rest,L"client_secret",L"CLIENT_SECRET");
    // Note: The resource must match the API for which you're using the access token..
    CkRestW_AddQueryParam(rest,L"resource",L"https://management.azure.com/");

    strResponseBody = CkRestW_fullRequestFormUrlEncoded(rest,L"POST",L"/TENANT_ID/oauth2/token");
    if (CkRestW_getLastMethodSuccess(rest) != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        return;
    }

    respStatusCode = CkRestW_getResponseStatusCode(rest);
    if (respStatusCode >= 400) {
        wprintf(L"Response Status Code = %d\n",respStatusCode);
        wprintf(L"Response Header:\n");
        wprintf(L"%s\n",CkRestW_responseHeader(rest));
        wprintf(L"Response Body:\n");
        wprintf(L"%s\n",strResponseBody);
        CkRestW_Dispose(rest);
        return;
    }

    json = CkJsonObjectW_Create();
    CkJsonObjectW_Load(json,strResponseBody);
    CkJsonObjectW_putEmitCompact(json,FALSE);
    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    // The result is an access token such as the following:

    // {
    //   "token_type": "Bearer",
    //   "expires_in": "3600",
    //   "ext_expires_in": "3600",
    //   "expires_on": "1557864616",
    //   "not_before": "1557860716",
    //   "resource": "https://management.azure.com/",
    //   "access_token": "eyJ0eXAiOiJKV1QiL ... 20UFDDOHEyUg"
    // }

    // We'll save this JSON to a file for other examples to use..
    CkJsonObjectW_WriteFile(json,L"qa_data/tokens/azureToken.json");


    CkRestW_Dispose(rest);
    CkJsonObjectW_Dispose(json);

    }