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Objective-C

Download Google OAuth2 Certs (JWK) and Load into Chilkat PublicKey Objects

See more OAuth2 Examples

Demonstrates how to download the JWK from https://www.googleapis.com/oauth2/v3/certs and load the public keys into Chilkat public key objects.

Chilkat Objective-C Downloads

Objective-C
#import <CkoHttp.h>
#import <NSString.h>
#import <CkoJsonObject.h>
#import <CkoPublicKey.h>

BOOL success = NO;

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

CkoHttp *http = [[CkoHttp alloc] init];

NSString *jwkStr = [http QuickGetStr: @"https://www.googleapis.com/oauth2/v3/certs"];
if (http.LastMethodSuccess == NO) {
    NSLog(@"%@",http.LastErrorText);
    return;
}

//  We have the following:

//      {
//        "keys": [
//  	{
//  	  "kid": "e8732db06287515556213b80acbcfd08cfb302a9",
//  	  "n": "4RIrO30287Wsq3gqXCMkUYMVAeI3H8...w2mbMNEBQ",
//  	  "kty": "RSA",
//  	  "e": "AQAB",
//  	  "alg": "RS256",
//  	  "use": "sig"
//  	},
//  	{
//  	  "kid": "8462a71da4f6d611fc0fecf0fc4ba9c37d65e6cd",
//  	  "e": "AQAB",
//  	  "n": "xT_ngLZNmT5GBtJZeTB...Ft4gK0eoFi0d3l8bcw",
//  	  "alg": "RS256",
//  	  "use": "sig",
//  	  "kty": "RSA"
//  	}
//        ]
//      }

CkoJsonObject *json = [[CkoJsonObject alloc] init];
success = [json Load: jwkStr];

CkoJsonObject *jsonKey = [[CkoJsonObject alloc] init];
CkoPublicKey *pubKey = [[CkoPublicKey alloc] init];
int numKeys = [[json SizeOfArray: @"keys"] intValue];
int i = 0;
while (i < numKeys) {
    json.I = [NSNumber numberWithInt: i];

    [json ObjectOf2: @"keys[i]" jsonObj: jsonKey];

    success = [pubKey LoadFromString: [jsonKey Emit]];
    if (success == NO) {
        NSLog(@"%@",pubKey.LastErrorText);
        return;
    }

    NSLog(@"%d",i);
    NSLog(@"%@",[pubKey GetPem: YES]);
    i = i + 1;
}

NSLog(@"%@",@"Success.");

//  Sample output:

//  0
//  -----BEGIN RSA PUBLIC KEY-----
//  MIIBCgKCAQEA4RIrO30287Wsq3gqXCMkUYMVAeI3H8LVE6IXR1krdFeGnZLiGUPw
//  cbkeVpXf3lmJdsStOg+jijces2DZCfPyIBiQuLYfxxmAZE6ErJ0QJFg1stwli2Pz
//  9ncYhFoqi8pXr7kEzEJBTzX4thuw56ydbGsshSEznPXoerCJOc7UI2+n0wFCWQ4Y
//  LHbh/PrWt4vdadyUUUW/QpQHXQLdD8q/Qwqdj0O9zlJE7R6Elw2E9EqnHyIGu1hm
//  LxhqrTru1M18SUhONYbVskV/BCEdVKs//X96849HorWQDCAgVMWfGsdMVq55FAdJ
//  680N5UmQDRynIZ4+PeNGN4S9iw2mbMNEBQIDAQAB
//  -----END RSA PUBLIC KEY-----
//  
//  1
//  -----BEGIN RSA PUBLIC KEY-----
//  MIIBCgKCAQEAxT/ngLZNmT5GBdkLtJZjNeTB+8B5yWgrq/e5eMZ1hrZhcmLK+dSn
//  IkpOPV8/OekV67EnQ7I4II2rcNJnHGrGKZziXO3XN2gtUHE+mBJC99oULSbX/QwB
//  Kz7gC/IBPq9EuxTt6Oq6fPkVQ9DbRIgWJSEGBF/KRaNl3kyAlIZfpY7XgHyJTTv8
//  E7yAcYKPR+36gzdl+ps0sDLKzUuAtZNq8llK0u80z6AtAUIYwWdkEhM9upy6keKI
//  TasIxcsO7M6kZPINUSbh6t5VAm8FuqRmxpgg+9c9/GQSGd89InVypoVzWLQ+wOGg
//  5G4H6JqIgtj0TRFt4gK0eoFi2U0d3l8bcwIDAQAB
//  -----END RSA PUBLIC KEY-----
//  
//  Success.