Unicode C
Unicode C
OAuth2 Token using IdentityServer4 with Client Credentials
See more OAuth2 Examples
Demonstrates how to get an OAuth2 access token using the client credential flow with IdentityServer4.Chilkat Unicode C Downloads
#include <C_CkHttpW.h>
#include <C_CkHttpResponseW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkJsonArrayW.h>
#include <C_CkHttpRequestW.h>
void ChilkatSample(void)
{
BOOL success;
HCkHttpW http;
HCkHttpResponseW resp;
HCkJsonObjectW json;
const wchar_t *tokenEndpoint;
HCkJsonArrayW grantTypes;
int clientCredentialsIdx;
HCkHttpRequestW req;
const wchar_t *accessToken;
success = FALSE;
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
http = CkHttpW_Create();
// The first step is to fetch your IdentityServer4's discovery document
// (OpenID Connect defines a discovery mechanism, called OpenID Connect Discovery, where an OpenID server publishes its metadata at a well-known URL,
// typically https://server.com/.well-known/openid-configuration
resp = CkHttpResponseW_Create();
success = CkHttpW_HttpNoBody(http,L"GET",L"https://localhost:5000/.well-known/openid-configuration",resp);
if (success == FALSE) {
wprintf(L"%s\n",CkHttpW_lastErrorText(http));
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
return;
}
if (CkHttpResponseW_getStatusCode(resp) != 200) {
wprintf(L"Received response status code %d\n",CkHttpResponseW_getStatusCode(resp));
wprintf(L"Response body containing error text or JSON:\n");
wprintf(L"%s\n",CkHttpResponseW_bodyStr(resp));
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
return;
}
json = CkJsonObjectW_Create();
success = CkJsonObjectW_Load(json,CkHttpResponseW_bodyStr(resp));
// We have the discovery document, which contains something like this:
// You can use this online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON
// {
// "issuer": "https://localhost:5000",
// "jwks_uri": "https://localhost:5000/.well-known/openid-configuration/jwks",
// "authorization_endpoint": "https://localhost:5000/connect/authorize",
// "token_endpoint": "https://localhost:5000/connect/token",
// "userinfo_endpoint": "https://localhost:5000/connect/userinfo",
// "end_session_endpoint": "https://localhost:5000/connect/endsession",
// "check_session_iframe": "https://localhost:5000/connect/checksession",
// "revocation_endpoint": "https://localhost:5000/connect/revocation",
// "introspection_endpoint": "https://localhost:5000/connect/introspect",
// "frontchannel_logout_supported": true,
// "frontchannel_logout_session_supported": true,
// "backchannel_logout_supported": true,
// "backchannel_logout_session_supported": true,
// "scopes_supported": [
// "openid",
// "profile",
// "email",
// "MyCompany.profile",
// "MyCompany.Identity.WebApi",
// "MyCompany.TriHub.WebApi",
// "offline_access"
// ],
// "claims_supported": [
// "sub",
// "updated_at",
// "locale",
// "zoneinfo",
// "birthdate",
// "gender",
// "website",
// "profile",
// "preferred_username",
// "nickname",
// "middle_name",
// "given_name",
// "family_name",
// "name",
// "picture",
// "email_verified",
// "email",
// "userId",
// "groups",
// "fullname"
// ],
// "grant_types_supported": [
// "authorization_code",
// "client_credentials",
// "refresh_token",
// "implicit",
// "password"
// ],
// "response_types_supported": [
// "code",
// "token",
// "id_token",
// "id_token token",
// "code id_token",
// "code token",
// "code id_token token"
// ],
// "response_modes_supported": [
// "form_post",
// "query",
// "fragment"
// ],
// "token_endpoint_auth_methods_supported": [
// "client_secret_basic",
// "client_secret_post"
// ],
// "subject_types_supported": [
// "public"
// ],
// "id_token_signing_alg_values_supported": [
// "RS256"
// ],
// "code_challenge_methods_supported": [
// "plain",
// "S256"
// ]
// }
//
// The next steps are to (1) get the token_endpoint,
// and (2) verify that the client_credentials grant type is supported.
tokenEndpoint = CkJsonObjectW_stringOf(json,L"token_endpoint");
grantTypes = CkJsonObjectW_ArrayOf(json,L"grant_types_supported");
clientCredentialsIdx = CkJsonArrayW_FindString(grantTypes,L"client_credentials",TRUE);
CkJsonArrayW_Dispose(grantTypes);
// If clientCredentialsIdx is less then zero (-1) then the "client_credentials" string was not found.
if (clientCredentialsIdx < 0) {
wprintf(L"The client credentials grant type is not supported.\n");
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
return;
}
// Request the access token using our Client ID and Client Secret.
// We're going to duplicate this CURL statement:
// curl --request POST \
// --url '<tokenEndpoint>' \
// --header 'content-type: application/x-www-form-urlencoded' \
// --data 'grant_type=client_credentials&client_id=CLIENT_ID&client_secret=CLIENT_SECRET'
req = CkHttpRequestW_Create();
CkHttpRequestW_putHttpVerb(req,L"POST");
CkHttpRequestW_putContentType(req,L"application/x-www-form-urlencoded");
CkHttpRequestW_AddParam(req,L"grant_type",L"client_credentials");
CkHttpRequestW_AddParam(req,L"client_id",L"CLIENT_ID");
CkHttpRequestW_AddParam(req,L"client_secret",L"CLIENT_SECRET"); CkHttpRequestW_putHttpVerb(req,L"POST");
success = CkHttpW_HttpReq(http,tokenEndpoint,req,resp);
if (success == FALSE) {
wprintf(L"%s\n",CkHttpW_lastErrorText(http));
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
CkHttpRequestW_Dispose(req);
return;
}
// Make sure we got a 200 response status code, otherwise it's an error.
if (CkHttpResponseW_getStatusCode(resp) != 200) {
wprintf(L"POST to token endpoint failed.\n");
wprintf(L"Received response status code %d\n",CkHttpResponseW_getStatusCode(resp));
wprintf(L"Response body containing error text or JSON:\n");
wprintf(L"%s\n",CkHttpResponseW_bodyStr(resp));
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
CkHttpRequestW_Dispose(req);
return;
}
success = CkJsonObjectW_Load(json,CkHttpResponseW_bodyStr(resp));
// Our JSON response should contain this:
// {
// "access_token":"eyJz93a...k4laUWw",
// "token_type":"Bearer",
// "expires_in":86400
// }
// Get the access token:
accessToken = CkJsonObjectW_stringOf(json,L"access_token");
// The access token is what gets added to "Authorization: Bearer <access_token>"
// for the subsequent REST API calls..
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
CkHttpRequestW_Dispose(req);
}