(Delphi DLL) Wish for Merchants -- Get OAuth2 Access Token for Desktop App

Demonstrates how to get a Wish for Merchants OAuth2 access token from a desktop application or script.

Note: This example requires Chilkat v10.1.2 or greater.

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, OAuth2, StringBuilder;

...

procedure TForm1.Button1Click(Sender: TObject);
var
oauth2: HCkOAuth2;
url: PWideChar;
success: Boolean;
numMsWaited: Integer;
sbJson: HCkStringBuilder;

begin
// To further clarify, see OAuth 2.0 Authorization Flow

// This example is for desktop applicatons (it is not for code that runs on a web server).

// This is the way to initially obtain the OAuth2 access token.  Afterwards it can be 
// repeatedly refreshed without user interaction, as shown in this example: Refresh Wish OAuth2 Access Token.

oauth2 := CkOAuth2_Create();

// Wish OAuth2 does not allow a localhost callback URI such as "http://localhost:<portNumber>/"
// For a desktop app, you must provide a script on your web server to redirect to "http://localhost/<portNumber>"

// Your applicaton must use your own public web server as an intermediate
// to receive and forward the redirect to localhost.
// See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost
CkOAuth2_putAppCallbackUrl(oauth2,'https://yourwebserver.com/OAuth2.php');
CkOAuth2_putListenPort(oauth2,3017);

CkOAuth2_putAuthorizationEndpoint(oauth2,'https://merchant.wish.com/v3/oauth/authorize');
CkOAuth2_putTokenEndpoint(oauth2,'https://merchant.wish.com/api/v3/oauth/access_token');

CkOAuth2_putUncommonOptions(oauth2,'EXCHANGE_CODE_FOR_TOKEN_USING_GET');

// Replace these with actual values.
CkOAuth2_putClientId(oauth2,'WISH-CLIENT-ID');
CkOAuth2_putClientSecret(oauth2,'WISH-CLIENT-SECRET');

CkOAuth2_putScope(oauth2,'');

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
url := CkOAuth2__startAuth(oauth2);
if (CkOAuth2_getLastMethodSuccess(oauth2) <> True) then
  begin
    Memo1.Lines.Add(CkOAuth2__lastErrorText(oauth2));
    Exit;
  end;

Memo1.Lines.Add('url = ' + url);

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success := CkOAuth2_LaunchBrowser(oauth2,url);
if (success = False) then
  begin
    Memo1.Lines.Add(CkOAuth2__lastErrorText(oauth2));
    Exit;
  end;

// Wait for the user to approve or deny authorization in the browser.
numMsWaited := 0;
while (numMsWaited < 90000) and (CkOAuth2_getAuthFlowState(oauth2) < 3) do
  begin
    CkOAuth2_SleepMs(oauth2,100);
    numMsWaited := numMsWaited + 100;
  end;

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect - The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response - The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (CkOAuth2_getAuthFlowState(oauth2) < 3) then
  begin
    CkOAuth2_Cancel(oauth2);
    Memo1.Lines.Add('No response from the browser!');
    Exit;
  end;

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success - OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied - OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure - OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (CkOAuth2_getAuthFlowState(oauth2) = 5) then
  begin
    Memo1.Lines.Add('OAuth2 failed to complete.');
    Memo1.Lines.Add(CkOAuth2__failureInfo(oauth2));
    Exit;
  end;

if (CkOAuth2_getAuthFlowState(oauth2) = 4) then
  begin
    Memo1.Lines.Add('OAuth2 authorization was denied.');
    Memo1.Lines.Add(CkOAuth2__accessTokenResponse(oauth2));
    Exit;
  end;

if (CkOAuth2_getAuthFlowState(oauth2) <> 3) then
  begin
    Memo1.Lines.Add('Unexpected AuthFlowState:' + IntToStr(CkOAuth2_getAuthFlowState(oauth2)));
    Exit;
  end;

// Save the full JSON access token response to a file.
sbJson := CkStringBuilder_Create();
CkStringBuilder_Append(sbJson,CkOAuth2__accessTokenResponse(oauth2));
CkStringBuilder_WriteFile(sbJson,'qa_data/tokens/wish.json','utf-8',False);

// The full JSON received looks like this:
// {
//   "message": "",
//   "code": 0,
//   "data": {
//     "access_token": "15af1c191c1243b029bc1660b5c08ce7",
//     "scopes": [
//       "epc:read",
//       "epc:write",
//       "fbs:read",
//       "fbs:write",
//       "fbw:read",
//       "fbw:write",
//       "infractions:read",
//       "infractions:write",
//       "insurance:read",
//       "insurance:write",
//       "loans:read",
//       "loans:write",
//       "merchant:read",
//       "merchant:write",
//       "notifications:read",
//       "notifications:write",
//       "orders:read",
//       "orders:write",
//       "payments:read",
//       "payments:write",
//       "penalties:read",
//       "penalties:write",
//       "product_boost:read",
//       "product_boost:write",
//       "products:read",
//       "products:write",
//       "ratings:read",
//       "ratings:write",
//       "returns:read",
//       "returns:write",
//       "tickets:read",
//       "tickets:write"
//     ],
//     "merchant_id": "5eb3f605178f5be2c784fa02",
//     "expiry_time": "2020-12-17T16:55:09.594+00:00",
//     "refresh_token": "55a38e44df674a1e859891624b2c4c23"
//   }
// }

Memo1.Lines.Add('OAuth2 authorization granted!');
Memo1.Lines.Add('Access Token = ' + CkOAuth2__accessToken(oauth2));

CkOAuth2_Dispose(oauth2);
CkStringBuilder_Dispose(sbJson);

end;