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C

Okta Client Credentials FLow

See more Okta OAuth/OIDC Examples

The Client Credentials flow is recommended for use in machine-to-machine authentication. Your application will need to securely store its Client ID and Secret and pass those to Okta in exchange for an access token. At a high-level, the flow only has two steps:
  • Your application passes its client credentials to your Okta authorization server.
  • If the credentials are accurate, Okta responds with an access token.

Note: This example uses "customScope". You'll replace it with whatever scope(s) you've defined for your app. Scopes are defined in your Authorization Server. See Okta Authorization Server / Scopes

Chilkat C Downloads

C
#include <C_CkHttp.h>
#include <C_CkHttpRequest.h>
#include <C_CkHttpResponse.h>
#include <C_CkStringBuilder.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttp http;
    HCkHttpRequest req;
    HCkHttpResponse resp;
    HCkStringBuilder sbResponseBody;
    HCkJsonObject jResp;
    int respStatusCode;
    const char *access_token;
    const char *token_type;
    int expires_in;
    const char *scope;

    success = FALSE;

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

    http = CkHttp_Create();

    // Implements the following CURL command:

    // curl --request POST \
    //   --url https://{yourOktaDomain}/oauth2/default/v1/token \
    //   --header 'accept: application/json' \
    //   --user "client_id:client_secret" \
    //   --header 'cache-control: no-cache' \
    //   --header 'content-type: application/x-www-form-urlencoded' \
    //   --data 'grant_type=client_credentials&scope=customScope'

    CkHttp_putLogin(http,"client_id");
    CkHttp_putPassword(http,"client_secret");

    req = CkHttpRequest_Create();
    CkHttpRequest_putHttpVerb(req,"POST");
    CkHttpRequest_putPath(req,"/oauth2/default/v1/token");
    CkHttpRequest_putContentType(req,"application/x-www-form-urlencoded");
    CkHttpRequest_AddParam(req,"grant_type","client_credentials");
    CkHttpRequest_AddParam(req,"scope","customScope");

    CkHttpRequest_AddHeader(req,"accept","application/json");

    resp = CkHttpResponse_Create();
    success = CkHttp_HttpReq(http,"https://{yourOktaDomain}/oauth2/default/v1/token",req,resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkHttp_Dispose(http);
        CkHttpRequest_Dispose(req);
        CkHttpResponse_Dispose(resp);
        return;
    }

    sbResponseBody = CkStringBuilder_Create();
    CkHttpResponse_GetBodySb(resp,sbResponseBody);
    jResp = CkJsonObject_Create();
    CkJsonObject_LoadSb(jResp,sbResponseBody);
    CkJsonObject_putEmitCompact(jResp,FALSE);

    printf("Response Body:\n");
    printf("%s\n",CkJsonObject_emit(jResp));

    respStatusCode = CkHttpResponse_getStatusCode(resp);
    printf("Response Status Code = %d\n",respStatusCode);
    if (respStatusCode >= 400) {
        printf("Response Header:\n");
        printf("%s\n",CkHttpResponse_header(resp));
        printf("Failed.\n");
        CkHttp_Dispose(http);
        CkHttpRequest_Dispose(req);
        CkHttpResponse_Dispose(resp);
        CkStringBuilder_Dispose(sbResponseBody);
        CkJsonObject_Dispose(jResp);
        return;
    }

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

    // {
    //   "access_token": "eyJraWQiO ... B2CnCLj7GRUW3mQ",
    //   "token_type": "Bearer",
    //   "expires_in": 3600,
    //   "scope": "customScope"
    // }

    // Sample code for parsing the JSON response...
    // Use the following online tool to generate parsing code from sample JSON:
    // Generate Parsing Code from JSON

    access_token = CkJsonObject_stringOf(jResp,"access_token");
    token_type = CkJsonObject_stringOf(jResp,"token_type");
    expires_in = CkJsonObject_IntOf(jResp,"expires_in");
    scope = CkJsonObject_stringOf(jResp,"scope");


    CkHttp_Dispose(http);
    CkHttpRequest_Dispose(req);
    CkHttpResponse_Dispose(resp);
    CkStringBuilder_Dispose(sbResponseBody);
    CkJsonObject_Dispose(jResp);

    }