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Unicode C

Add Custom Claims to JWT for Google Service Account OAuth2

Demonstrates how add custom claims to the JWT when getting a Google API OAuth2 access token using a JSON service account private key.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkFileAccessW.h>
#include <C_CkAuthGoogleW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkSocketW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkFileAccessW fac;
    const wchar_t *jsonKey;
    HCkAuthGoogleW gAuth;
    HCkJsonObjectW moreClaims;
    HCkSocketW tlsSock;

    success = FALSE;

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

    //  First load the JSON key into a string.
    fac = CkFileAccessW_Create();
    jsonKey = CkFileAccessW_readEntireTextFile(fac,L"qa_data/googleApi/ChilkatTest-ab2ecd52ef98.json",L"utf-8");
    if (CkFileAccessW_getLastMethodSuccess(fac) != TRUE) {
        wprintf(L"%s\n",CkFileAccessW_lastErrorText(fac));
        CkFileAccessW_Dispose(fac);
        return;
    }

    //  A JSON private key should look like this:

    //  	{
    //  	  "type": "service_account",
    //  	  "project_id": "chilkattest-1350",
    //  	  "private_key_id": "fa2e36ee26986eab628b59868af8bec1d1c64c38",
    //  	  "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvgIjFa...28N64N2n1E4FYzBZjSdy\n-----END PRIVATE KEY-----\n",
    //  	  "client_email": "598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a@developer.gserviceaccount.com",
    //  	  "client_id": "598922945226-00rb0ppfg0snd9jo7bhvd4v17jtj2d3a.apps.googleusercontent.com",
    //  	  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    //  	  "token_uri": "https://accounts.google.com/o/oauth2/token",
    //  	  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    //  	  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a%40developer.gserviceaccount.com"
    //  	}

    gAuth = CkAuthGoogleW_Create();
    CkAuthGoogleW_putJsonKey(gAuth,jsonKey);

    //  Choose a scope.
    CkAuthGoogleW_putScope(gAuth,L"https://www.googleapis.com/auth/cloud-platform");

    //  Request an access token that is valid for this many seconds.
    CkAuthGoogleW_putExpireNumSeconds(gAuth,3600);

    //  If the application is requesting delegated access:
    //  The email address of the user for which the application is requesting delegated access,
    //  then set the email address here. (Otherwise leave it empty.)
    CkAuthGoogleW_putSubEmailAddress(gAuth,L"");

    //  --------------------------------------------------------------------------------------
    //  To add custom claims, create JSON containing the claims to be added and call AddClaims.
    moreClaims = CkJsonObjectW_Create();
    CkJsonObjectW_UpdateString(moreClaims,L"claimAbc",L"valueAbc");
    CkJsonObjectW_UpdateString(moreClaims,L"claimXyz",L"valueXyz");
    //  ...
    CkAuthGoogleW_AddClaims(gAuth,moreClaims);
    //  --------------------------------------------------------------------------------------

    //  Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
    //  The Chilkat socket object is used so that the connection can be established
    //  through proxies or an SSH tunnel if desired.
    tlsSock = CkSocketW_Create();
    success = CkSocketW_Connect(tlsSock,L"www.googleapis.com",443,TRUE,5000);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSocketW_lastErrorText(tlsSock));
        CkFileAccessW_Dispose(fac);
        CkAuthGoogleW_Dispose(gAuth);
        CkJsonObjectW_Dispose(moreClaims);
        CkSocketW_Dispose(tlsSock);
        return;
    }

    //  Send the request to obtain the access token.
    success = CkAuthGoogleW_ObtainAccessToken(gAuth,tlsSock);
    if (success != TRUE) {
        wprintf(L"%s\n",CkAuthGoogleW_lastErrorText(gAuth));
        CkFileAccessW_Dispose(fac);
        CkAuthGoogleW_Dispose(gAuth);
        CkJsonObjectW_Dispose(moreClaims);
        CkSocketW_Dispose(tlsSock);
        return;
    }

    //  Examine the access token:
    wprintf(L"Access Token: %s\n",CkAuthGoogleW_accessToken(gAuth));


    CkFileAccessW_Dispose(fac);
    CkAuthGoogleW_Dispose(gAuth);
    CkJsonObjectW_Dispose(moreClaims);
    CkSocketW_Dispose(tlsSock);

    }