(C#) Datev OAuth2 Access Token

See more Datev Examples

Note: This example requires Chilkat v10.1.3 or greater.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

// To further clarify, see OAuth 2.0 Authorization Flow

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

// Your Datev app should use "http://localhost" (no trailing forward slash) for the redirect URL.
oauth2.ListenPort = 3017;

// 

oauth2.AuthorizationEndpoint = "https://login.datev.de/openidsandbox/authorize";
oauth2.TokenEndpoint = "https://sandbox-api.datev.de/token";

// Replace this with your actual client ID.
oauth2.ClientId = "DATEV_CLIENT_ID";
oauth2.ClientSecret = "DATEV_CLIENT_SECRET";

oauth2.CodeChallenge = true;
oauth2.CodeChallengeMethod = "S256";

oauth2.Scope = "openid profile email datev:accounting:clients accounting:documents datev:accounting:extf-files-import";

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

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
bool success = oauth2.LaunchBrowser(url);
if (success == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

// Wait for the interactive user to grant permission in the interactive browser session.
// We'll wait for a max of 90 seconds.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited + 100;
}

// If there was no response from the browser within 90 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 (oauth2.AuthFlowState < 3) {
    oauth2.Cancel();
    Debug.WriteLine("No response from the browser!");
    return;
}

// 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 (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/datev.json","utf-8",false);

// The saved JSON response looks like this:

// {
// 	"refresh_token": "ZDA5Y .... FFhTXc9",
// 	"refresh_token_expires_in": 39600,
// 	"id_token": "eyJ .... Q9w",
// 	"access_token": "MTM .... 1UDA9",
// 	"token_type": "bearer",
// 	"expires_in": 900		
// }

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