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C#

Quickbooks OAuth2 in a Desktop App

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

Chilkat C# Downloads

C#
bool success = false;

//  To further clarify, see OAuth 2.0 Authorization Flow

//  ------------------------------------------------------------------------------------------------
//  IMPORTANT: You first need to define an App in the Quickbooks Developer Dashboard.
//  See How to Create an App in QuickBooks Developer Dashboard
//  ------------------------------------------------------------------------------------------------

//  This example is for desktop applicatons (it is not for code that runs on a web server).
//  You'll need to add a line (or a few lines of code) to popup a web browser that navigates to a URL.

//  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 Quickbooks OAuth2 Access Token.

Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();

//  QuickBooks OAuth2 allows for an "http://localhost:<portNumber>/" callback URL for sandbox testing,
//  but not for production.

//  In production, 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

oauth2.AppCallbackUrl = "https://yourwebserver.com/OAuth2.php";
oauth2.ListenPort = 3017;

oauth2.AuthorizationEndpoint = "https://appcenter.intuit.com/connect/oauth2";
oauth2.TokenEndpoint = "https://oauth.platform.intuit.com/oauth2/v1/tokens/bearer";

//  Replace these with actual values.
oauth2.ClientId = "QUICKBOOKS-CLIENT-ID";
oauth2.ClientSecret = "QUICKBOOKS-CLIENT-SECRET";
oauth2.UseBasicAuth = true;
oauth2.CodeChallenge = false;

//  Indicate the desired access.  Possible scopes that can appear in the list are:
//  com.intuit.quickbooks.accounting:  QuickBooks Online API
//  com.intuit.quickbooks.payment:  QuickBooks Payments API
//  openid:  OpenID Connect processing
//  profile:  user's given and family names
//  email:  user's email address
//  phone:  user's phone number
//  address:  user's physical address
oauth2.Scope = "com.intuit.quickbooks.accounting";

//  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
string url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

Debug.WriteLine("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 = oauth2.LaunchBrowser(url);
if (success == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

//  Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited + 100;
}

//  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 (oauth2.AuthFlowState < 3) {
    oauth2.Cancel();
    Debug.WriteLine("No response from the browser!");
    return;
}

//  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 (oauth2.AuthFlowState == 5) {
    Debug.WriteLine("OAuth2 failed to complete.");
    Debug.WriteLine(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    Debug.WriteLine("OAuth2 authorization was denied.");
    Debug.WriteLine(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState != 3) {
    Debug.WriteLine("Unexpected AuthFlowState:" + Convert.ToString(oauth2.AuthFlowState));
    return;
}

//  Save the full JSON access token response to a file.
Chilkat.StringBuilder sbJson = new Chilkat.StringBuilder();
sbJson.Append(oauth2.AccessTokenResponse);
sbJson.WriteFile("qa_data/tokens/qb-access-token.json","utf-8",false);

//  The full JSON received looks like this:
//  {
//    "expires_in": 3600,
//    "x_refresh_token_expires_in": 8726400,
//    "refresh_token": "L011546037639r ... 3vR2DrbOmg0Sdagw",
//    "access_token": "eyJlbmMiOiJBMTI4Q0 ... oETJEMbeggg",
//    "token_type": "bearer"
//  }

Debug.WriteLine("OAuth2 authorization granted!");
Debug.WriteLine("Access Token = " + oauth2.AccessToken);

//  Get the realmId if needed...
//  See About the QuickBooks REST API Realm ID, also known as Company ID
string realmId = oauth2.GetRedirectRequestParam("realmId");
if (oauth2.LastMethodSuccess == true) {
    Debug.WriteLine("realmId: " + realmId);
}
else {
    Debug.WriteLine("No realmId was provided.");
}