(Delphi DLL) Check PayPal Access Token Expiration

Checks to see if the PayPal access token expired.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, CkDateTime, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
json: HCkJsonObject;
success: Boolean;
dateTime: HCkDateTime;
bLocalTime: Boolean;
dtNow: Integer;
dtCreate: Integer;
numSeconds: Integer;
expires_in: Integer;

begin
// Note: Requires Chilkat v9.5.0.64 or greater.

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

// In the example linked here: PayPal OAuth2 Token,
// we fetched a PayPal access token and saved it to a JSON file.
// We also recorded the current date/time.
// Load this JSON file and compare the current date/time with the fetch date/time
// and the "expires_in" value to see if the token is expired.

json := CkJsonObject_Create();
success := CkJsonObject_LoadFile(json,'qa_data/tokens/paypal.json');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load access key json file.');
    Exit;
  end;

// Get the current date/time.
dateTime := CkDateTime_Create();
bLocalTime := False;
dtNow := CkDateTime_GetAsUnixTime(dateTime,bLocalTime);

// Get the access token create date/time
dtCreate := CkJsonObject_IntOf(json,'tokenCreateTimeUtc');

// Find out how many seconds have elapsed.
numSeconds := dtNow - dtCreate;

// Get the expires_in value from the JSON.
expires_in := CkJsonObject_IntOf(json,'expires_in');

Memo1.Lines.Add('token age (in seconds) = ' + IntToStr(numSeconds));
Memo1.Lines.Add('expires_in = ' + IntToStr(expires_in));

// If the token expired, or if it will expire in 5 minutes or less,
// get another token.
if (numSeconds < (expires_in - 300)) then
  begin
    Memo1.Lines.Add('The token is not yet expired.  No need to fetch another.');
    Exit;
  end;

Memo1.Lines.Add('Time to fetch a new access token...');

// Get another token..
// See the example at Get PayPal OAuth2 Token
// to get another token..

CkJsonObject_Dispose(json);
CkDateTime_Dispose(dateTime);

end;