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Delphi DLL Requires Chilkat v11.0.0+

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 Delphi DLL Downloads

Delphi DLL
var
success: Boolean;
http: HCkHttp;
jwkStr: PWideChar;
json: HCkJsonObject;
jsonKey: HCkJsonObject;
pubKey: HCkPublicKey;
numKeys: Integer;
i: Integer;

begin
success := False;

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

http := CkHttp_Create();

jwkStr := CkHttp__quickGetStr(http,'https://www.googleapis.com/oauth2/v3/certs');
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

//  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"
//  	}
//        ]
//      }

json := CkJsonObject_Create();
success := CkJsonObject_Load(json,jwkStr);

jsonKey := CkJsonObject_Create();
pubKey := CkPublicKey_Create();
numKeys := CkJsonObject_SizeOfArray(json,'keys');
i := 0;
while i < numKeys do
  begin
    CkJsonObject_putI(json,i);

    CkJsonObject_ObjectOf2(json,'keys[i]',jsonKey);

    success := CkPublicKey_LoadFromString(pubKey,CkJsonObject__emit(jsonKey));
    if (success = False) then
      begin
        Memo1.Lines.Add(CkPublicKey__lastErrorText(pubKey));
        Exit;
      end;

    Memo1.Lines.Add(IntToStr(i));
    Memo1.Lines.Add(CkPublicKey__getPem(pubKey,True));
    i := i + 1;
  end;

Memo1.Lines.Add('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.

CkHttp_Dispose(http);
CkJsonObject_Dispose(json);
CkJsonObject_Dispose(jsonKey);
CkPublicKey_Dispose(pubKey);