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Delphi DLL Requires Chilkat v10.1.2+

Yahoo Mail OAuth2 Access Token for Desktop App

See more Yahoo Mail Examples

Demonstrates how to get a Yahoo Email OAuth2 access token from a desktop application or script.

Chilkat Delphi DLL Downloads

Delphi DLL
var
success: Boolean;
oauth2: HCkOAuth2;
url: PWideChar;
numMsWaited: Integer;
sbJson: HCkStringBuilder;

begin
success := False;

//  First, you must define your app in Yahoo Developer (https://developer.yahoo.com/apps/) like this:

//  image

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

oauth2 := CkOAuth2_Create();

//  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/oauth_redirect');
CkOAuth2_putListenPort(oauth2,3017);

CkOAuth2_putAuthorizationEndpoint(oauth2,'https://api.login.yahoo.com/oauth2/request_auth');
CkOAuth2_putTokenEndpoint(oauth2,'https://api.login.yahoo.com/oauth2/get_token');

//  Replace these with actual values.
CkOAuth2_putClientId(oauth2,'CLIENT_ID');
CkOAuth2_putClientSecret(oauth2,'CLIENT_SECRET');

//  Do not send the "scope" query param for Yahoo OAuth2.
CkOAuth2_putUncommonOptions(oauth2,'NO_OAUTH2_SCOPE');

//  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) = False) 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/yahooMail.json','utf-8',False);

//  The saved JSON response looks like this:

//  {
//    "access_token": "kCVQdnOdul...LHucA--",
//    "refresh_token": "AIenVXETSo0jklFBVkPS8vVm8E.Ej9ToRG.xDbDYmZ65WIs5t6CZhDrD",
//    "expires_in": 3600,
//    "token_type": "bearer",
//    "xoauth_yahoo_guid": "HGDQCVF5JB4YDOWHITQJFBHCWA"
//  }

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

CkOAuth2_Dispose(oauth2);
CkStringBuilder_Dispose(sbJson);