(Delphi ActiveX) PayPal - Authorize a Payment

Creates an authorization for a payment. This is for the case where the payment will first be authorized, and then captured at a later date. (In other words, the buyer is providing his/her credit card information now, and the actual charge (capture) will take place at a later time.)

Creating the authorization is the same as creating "sale" payment, except the intent is set to "authorize" instead of "sale".

This example requests an authorization for a credit card payment (using a credit card ID previoulsy stored in the PayPal vault).

Note: This example requires Chilkat v9.5.0.65 or greater.

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
jsonToken: TChilkatJsonObject;
sbAuth: TChilkatStringBuilder;
rest: TChilkatRest;
bAutoReconnect: Integer;
success: Integer;
json: TChilkatJsonObject;
sbJsonRequest: TChilkatStringBuilder;
sbJsonResponse: TChilkatStringBuilder;

begin
// Note: Requires Chilkat v9.5.0.65 or greater.

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

// Load our previously obtained access token. (see PayPal OAuth2 Access Token)
jsonToken := TChilkatJsonObject.Create(Self);
jsonToken.LoadFile('qa_data/tokens/paypal.json');

// Build the Authorization request header field value.
sbAuth := TChilkatStringBuilder.Create(Self);
// token_type should be "Bearer"
sbAuth.Append(jsonToken.StringOf('token_type'));
sbAuth.Append(' ');
sbAuth.Append(jsonToken.StringOf('access_token'));

// Make the initial connection.
// A single REST object, once connected, can be used for many PayPal REST API calls.
// The auto-reconnect indicates that if the already-established HTTPS connection is closed,
// then it will be automatically re-established as needed.
rest := TChilkatRest.Create(Self);
bAutoReconnect := 1;
success := rest.Connect('api.sandbox.paypal.com',443,1,bAutoReconnect);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// ----------------------------------------------------------------------------------------------
// The code above this comment could be placed inside a function/subroutine within the application
// because the connection does not need to be made for every request.  Once the connection is made
// the app may send many requests..
// ----------------------------------------------------------------------------------------------

// Build the JSON containing the transaction information.
json := TChilkatJsonObject.Create(Self);
json.EmitCompact := 0;
json.UpdateString('intent','authorize');
json.UpdateString('payer.payment_method','credit_card');
json.UpdateString('payer.funding_instruments[0].credit_card_token.credit_card_id','CARD-52W84623JH8043102LA3CLGA');
json.UpdateString('payer.funding_instruments[0].credit_card_token.payer_id','user12345');
json.UpdateString('transactions[0].amount.total','6.70');
json.UpdateString('transactions[0].amount.currency','USD');
json.UpdateString('transactions[0].description','This is the payment transaction description.');

Memo1.Lines.Add(json.Emit());

// The JSON created by the above code is this:

// 	{ 
// 	  "intent": "authorize",
// 	  "payer": { 
// 	    "payment_method": "credit_card",
// 	    "funding_instruments": [
// 	      { 
// 	        "credit_card_token": { 
// 	          "credit_card_id": "CARD-52W84623JH8043102LA3CLGA",
// 	          "payer_id": "user12345"
// 	        }
// 	      }
// 	    ]
// 	  },
// 	  "transactions": [
// 	    { 
// 	      "amount": { 
// 	        "total": "6.70",
// 	        "currency": "USD"
// 	      },
// 	      "description": "This is the payment transaction description."
// 	    }
// 	  ]
// 	}

rest.AddHeader('Authorization',sbAuth.GetAsString());
rest.AddHeader('Content-Type','application/json');

// Send the POST request containign the JSON in the request body, and get the JSON response.
sbJsonRequest := TChilkatStringBuilder.Create(Self);
json.EmitCompact := 1;
json.EmitSb(sbJsonRequest.ControlInterface);
sbJsonResponse := TChilkatStringBuilder.Create(Self);
success := rest.FullRequestSb('POST','/v1/payments/payment',sbJsonRequest.ControlInterface,sbJsonResponse.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

json.EmitCompact := 0;
json.LoadSb(sbJsonResponse.ControlInterface);

Memo1.Lines.Add('Response Status Code = ' + IntToStr(rest.ResponseStatusCode));

// Did we get a 201 success response?
if (rest.ResponseStatusCode <> 201) then
  begin
    Memo1.Lines.Add(json.Emit());
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

// Sample JSON response is shown below.
Memo1.Lines.Add(json.Emit());
// The authorization ID found in the related_resources is used to capture the payment at a later time.
Memo1.Lines.Add('authorization id: ' + json.StringOf('transactions[0].related_resources[0].authorization.id'));
Memo1.Lines.Add('success');

// ------------------------------------------------
// A sample JSON response:

// 	{ 
// 	  "id": "PAY-2CY489250W145633HLA3DK3Y",
// 	  "create_time": "2016-11-24T00:33:51Z",
// 	  "update_time": "2016-11-24T00:33:58Z",
// 	  "state": "approved",
// 	  "intent": "authorize",
// 	  "payer": { 
// 	    "payment_method": "credit_card",
// 	    "funding_instruments": [
// 	      { 
// 	        "credit_card_token": { 
// 	          "credit_card_id": "CARD-52W84623JH8043102LA3CLGA",
// 	          "payer_id": "user12345",
// 	          "last4": "9974",
// 	          "type": "visa",
// 	          "expire_month": "9",
// 	          "expire_year": "2021"
// 	        }
// 	      }
// 	    ]
// 	  },
// 	  "transactions": [
// 	    { 
// 	      "amount": { 
// 	        "total": "6.70",
// 	        "currency": "USD",
// 	        "details": { 
// 	          "subtotal": "6.70"
// 	        }
// 	      },
// 	      "description": "This is the payment transaction description.",
// 	      "related_resources": [
// 	        { 
// 	          "authorization": { 
// 	            "id": "7X8332687A4929542",
// 	            "create_time": "2016-11-24T00:33:51Z",
// 	            "update_time": "2016-11-24T00:33:58Z",
// 	            "amount": { 
// 	              "total": "6.70",
// 	              "currency": "USD",
// 	              "details": { 
// 	                "subtotal": "6.70"
// 	              }
// 	            },
// 	            "state": "authorized",
// 	            "parent_payment": "PAY-2CY489250W145633HLA3DK3Y",
// 	            "valid_until": "2016-12-23T00:33:51Z",
// 	            "links": [
// 	              { 
// 	                "href": "https://api.sandbox.paypal.com/v1/payments/authorization/7X8332687A4929542",
// 	                "rel": "self",
// 	                "method": "GET"
// 	              },
// 	              { 
// 	                "href": "https://api.sandbox.paypal.com/v1/payments/authorization/7X8332687A4929542/capture",
// 	                "rel": "capture",
// 	                "method": "POST"
// 	              },
// 	              { 
// 	                "href": "https://api.sandbox.paypal.com/v1/payments/authorization/7X8332687A4929542/void",
// 	                "rel": "void",
// 	                "method": "POST"
// 	              },
// 	              { 
// 	                "href": "https://api.sandbox.paypal.com/v1/payments/payment/PAY-2CY489250W145633HLA3DK3Y",
// 	                "rel": "parent_payment",
// 	                "method": "GET"
// 	              }
// 	            ],
// 	            "processor_response": { 
// 	              "avs_code": "X",
// 	              "cvv_code": "M"
// 	            },
// 	            "fmf_details": {}
// 	          }
// 	        }
// 	      ]
// 	    }
// 	  ],
// 	  "links": [
// 	    { 
// 	      "href": "https://api.sandbox.paypal.com/v1/payments/payment/PAY-2CY489250W145633HLA3DK3Y",
// 	      "rel": "self",
// 	      "method": "GET"
// 	    }
// 	  ]
// 	}
end;