Delphi DLL

Constant Contact (v3) OAuth2 Access Token

See more Constant Contact Examples

Gets an OAuth2 access token for ConstantContact. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, FileAccess, OAuth2, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
oauth2: HCkOAuth2;
url: PWideChar;
numMsWaited: Integer;
json: HCkJsonObject;
fac: HCkFileAccess;

begin
success := False;

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

oauth2 := CkOAuth2_Create();

// This should be the port in the localhost callback URL for your app.  
// The callback URL would look like "http://localhost:3017/" if the port number is 3017.
// Make sure when defining your application (i.e. "My Applications" at  https://app.constantcontact.com/pages/dma/portal/)
// that the Redirect URI is exactly this:  "http://localhost:3017/".   You may use any port number as long as it agrees
// with the ListenPort here.  It is important to use "http" and not "https" in the callback URI.  The trailing "/" is also important.
CkOAuth2_putListenPort(oauth2,3017);

CkOAuth2_putAuthorizationEndpoint(oauth2,'https://api.cc.email/v3/idfed');
CkOAuth2_putTokenEndpoint(oauth2,'https://idfed.constantcontact.com/as/token.oauth2');

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

// Add one or more SPACE separated scopes
CkOAuth2_putScope(oauth2,'account_read account_update contact_data campaign_data');

// Begin the OAuth2 three-legged 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);

// Launch the system's default browser navigated to the URL.
success := CkOAuth2_LaunchBrowser(oauth2,url);
if (success = False) then
  begin
    Memo1.Lines.Add(CkOAuth2__lastErrorText(oauth2));
    Exit;
  end;

// Now wait for the authorization.
// We'll wait for a max of 30 seconds.
numMsWaited := 0;
while (numMsWaited < 30000) and (CkOAuth2_getAuthFlowState(oauth2) < 3) do
  begin
    CkOAuth2_SleepMs(oauth2,100);
    numMsWaited := numMsWaited + 100;
  end;

// If there was no response from the browser within 30 seconds, then 
// the AuthFlowState will be equal to 1 or 2.
// 1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
// 2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
// In that case, cancel the background task started in the call to StartAuth.
if (CkOAuth2_getAuthFlowState(oauth2) < 3) then
  begin
    CkOAuth2_Cancel(oauth2);
    Memo1.Lines.Add('No response from the browser!');
    Exit;
  end;

// Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
// The possible AuthFlowState values are:
// 3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
// 4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
// 5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
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;

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

// Get the full JSON response:
json := CkJsonObject_Create();
CkJsonObject_Load(json,CkOAuth2__accessTokenResponse(oauth2));
CkJsonObject_putEmitCompact(json,False);

// The JSON response looks like this:

// {
//   "access_token": "aEr4czHReESHUGcc2LRknzsMxUbW",
//   "refresh_token": "s2qH27ikM7r3Ia0LrZGDOIgKw0bubUotBdJ7fTtc7y",
//   "token_type": "Bearer"
// }

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

// Save the JSON to a file for future requests.
fac := CkFileAccess_Create();
CkFileAccess_WriteEntireTextFile(fac,'qa_data/tokens/constantContact.json',CkJsonObject__emit(json),'utf-8',False);

CkOAuth2_Dispose(oauth2);
CkJsonObject_Dispose(json);
CkFileAccess_Dispose(fac);

end;